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1: High Efficiency Speaker Asylum, RE: RIP Dr. Bruce Edgar (0.00)
Posted by JLH on 2021-01-19, 17:23:06 (165.225.0.75)
So sad to see this news. If it wasn't for Bruce, I would have never gotten into horns. .......
2: Tubes Asylum, 6BC7 (0.00)
Posted by JLH on 2018-12-15, 16:45:00 (98.222.190.144)
6AL5 is rated for 9mA each section. 6BC7 is rated for 12mA each section. You can use two tubes with all three internal diodes paralleled to form a full wave rectifier rated for 36mA. Regards, JLH ::: .......
3: K&K Audio / Lundahl Transformers, LL2745 compared to LL1692 (0.00)
Posted by JLH on 2018-12-08, 19:15:29 (98.222.190.144)
I need a step down transformer for a pre-amp project. Tube will have a plate impedance of approximately 1730 ohms and have a amplification factor of 7. Both the LL2745 and LL1692A have the appropriate .......
4: K&K Audio / Lundahl Transformers, RE: Sad news (0.00)
Posted by JLH on 2013-12-20, 19:26:42 (172.8.48.164)
Any time something like this happens it is a tragedy. My heart goes out to his family. This country needs to look at the declined state of its mental health services. Having worked in the medical fiel .......
5: High Efficiency Speaker Asylum, RE: Bruce Edgar Speaker Builder 3/80 Midrange Corner Horn (0.00)
Posted by JLH on 2013-12-12, 04:27:38 (69.174.58.44)
I don't ever recall seeing that article...interesting. .......
6: High Efficiency Speaker Asylum, RE: Bruce Edgar Speaker Builder 3/80 Midrange Corner Horn (0.00)
Posted by JLH on 2013-12-11, 12:24:36 (69.174.58.44)
What is the title of the article you are looking for? Was it the Show Horn or the Monolith Horn? .......
7: Tube DIY Asylum, Don't forget to factor in the DCR of the secondary (0.00)
Posted by JLH on 2013-09-09, 17:44:15 (172.8.53.65)
This is the math I use as an example: 5000/8 = 625 impedance ratio Rp=2K 2K/625 = 3.2 DCR of secondary = 0.8 ohm 3.2 + 0.8 = 4.0 ohms DF = 8/4.0 = 2.0 .......
8: MagneQuest/Peerless Forum, RE: No takers? What about the technical differenes. (0.00)
Posted by JLH on 2013-02-03, 21:30:19 (108.79.208.40)
Looking at using 811A and 812A interchangeably in a parafeed amp designed around a plate choke that will have a 15% cathode feedback winding. To handle the grid current, I'll be using a FET followe .......
9: MagneQuest/Peerless Forum, No takers? What about the technical differenes. (0.00)
Posted by JLH on 2013-01-30, 02:54:07 (69.174.58.44)
Since it doesn't look like anyone has compared these two transformers, what about their technical differences? What makes these two transformers different and what might be the effects of the design c .......
10: MagneQuest/Peerless Forum, Sound quality differences between EXO-050 and RH-PF (0.00)
Posted by JLH on 2013-01-11, 20:44:22 (99.130.189.198)
Didn't know if anyone has had the opportunity to compare The EXO-050 and RH-PF output transformers. If the power level was kept below 10 watts is there much difference between these two? Thanks guys. .......
11: Tube DIY Asylum, RE: Of course it can! - Show me (0.00)
Posted by JLH on 2011-06-24, 20:03:39 (76.252.40.104)
The fact that a transformer or choke can swing above B+ is irrelevant in the context of the discussion. The MOSFETs I use have an output impedance of around 6 ohms. By the time you get a transformer w .......
12: Tube DIY Asylum, And a transformer can do better? (0.00)
Posted by JLH on 2011-06-22, 20:01:18 (76.252.40.104)
A correctly executed MOSFET follower will have lower output impedance and almost zero phase shift across the entire audio spectrum in relation to an interstage transformer. In addition, a MOSFET follo .......
13: Tube DIY Asylum, Use a FET follower and be done with. (nt) (0.00)
Posted by JLH on 2011-06-21, 14:32:49 (76.252.40.104)
. .......
14: Tube DIY Asylum, RE: The 10:1 rule (0.00)
Posted by JLH on 2011-05-30, 13:26:52 (70.225.129.149)
If gain is the most important thing to you, then yes the higher impedance is handy. However, I use horns so I have gain to spare. Most systems have too much gain unless the person has planned it from .......
15: Tube DIY Asylum, RE: The 10:1 rule (0.00)
Posted by JLH on 2011-05-30, 13:17:38 (70.225.129.149)
I have found that the series resistor required to bring up the output impedance to 600 ohms to drive the 600 ohm LCR modules really hurts the sound. It ruins the dynamics. In this case the low output .......
16: Tube DIY Asylum, RE: "The 10:1 rule really doesn’t apply to pentodes." (0.00)
Posted by JLH on 2011-05-30, 13:02:36 (70.225.129.149)
Because of the pentode's high internal impedance. Just look at the pentode's plate curves, they are almost horizontal. Compare this to a triode's plate curves. Start drawing various load lines and see .......
17: Tube DIY Asylum, The 10:1 rule (0.00)
Posted by JLH on 2011-05-27, 05:05:37 (69.174.58.36)
The 10:1 rule really doesn’t apply to pentodes. I would agree that it’s a good idea for triodes, but traditionally it’s been common place for pentode circuits to see impedances much lower than Rp. I t .......
18: Tube DIY Asylum, If you want the best best go with a LCR phono (0.00)
Posted by JLH on 2011-05-25, 03:25:35 (69.174.58.36)
The best sounding phono stages I’ve built or heard have all been LCR types. The RC type phono stages sound artificial, etched and unnatural when compared to a good LCR. The LCR has a liquidity, cohere .......
19: Tube DIY Asylum, Not looking or discussing from the same view point. (0.00)
Posted by JLH on 2011-03-13, 12:07:57 (69.174.58.44)
I agree that by and large we design our circuits to operate from a fixed voltage source. Since we do not live in a perfect world and “Ideal” current and voltage sources do not exist, we strive to have .......
20: Tubes Asylum, I wish Allen was still with us... (0.00)
Posted by JLH on 2011-03-10, 11:15:15 (69.174.58.36)
He could have given you a complete rundown on the do's and dont's with CFs. Sigh... .......
21: Tube DIY Asylum, RE: ????? on power supply AGAIN!!!!!! (0.00)
Posted by JLH on 2011-03-10, 11:12:45 (69.174.58.36)
If you want an actively regulated power supply, then I would not hang anything on its output like extra chokes or caps. Most regulated power supplies operate off of some kind of feedback. Adding extra .......
22: Tube DIY Asylum, RE: All the EE books must be wrong then (0.00)
Posted by JLH on 2011-03-10, 08:19:26 (69.174.58.44)
Yes, Ohm's Law tells us that the lower impedance device will get a larger percentage of the available current. The larger you make the cap, the larger the percentage of available current resouces are .......
23: Tube DIY Asylum, RE: All the EE books must be wrong then (0.00)
Posted by JLH on 2011-03-10, 08:15:14 (69.174.58.44)
Last time I checked PSUDII did not have provisions for simulating an output tube. .......
24: Tube DIY Asylum, RE: Because... (0.00)
Posted by JLH on 2011-03-10, 08:13:43 (69.174.58.44)
If a forward biased diode couldn't pass AC then LED biasing of tubes or other devices would be impossible. I thought part of the discussion was whether it is more desirable to have your diodes aways c .......
25: High Efficiency Speaker Asylum, Economies of scale (0.00)
Posted by JLH on 2011-03-10, 08:08:34 (69.174.58.44)
http://en.wikipedia.org/wiki/Economies_of_scale .......
26: Tube DIY Asylum, RE: Because... (0.00)
Posted by JLH on 2011-03-09, 19:05:56 (70.225.138.36)
Does having continuous diode conduction really sound better? Do we really know for certain? When I look backwards into the power supply I see an open electrical pathway for all the garbage that lives .......
27: Tube DIY Asylum, All the EE books must be wrong then (0.00)
Posted by JLH on 2011-03-09, 18:53:07 (70.225.138.36)
So you are denying that there is any truth to all the EE books that state that the impedance of a capacitor varies as dV/dI changes. If you want to throw all physics out the window its fine with me. I .......
28: Tube DIY Asylum, RE: See ...."You're neglecting the behavior of capacitors" (0.00)
Posted by JLH on 2011-03-09, 07:45:05 (69.174.58.44)
The lower the internal impedance of your output devices, the less the high capacitance is able to compete with them. OTL and solid state are normally lower voltage, high current topologies and are not .......
29: Tube DIY Asylum, Because... (0.00)
Posted by JLH on 2011-03-09, 07:34:21 (69.174.58.44)
Because as delta V becomes larger, delta Z must go down if current draw is held constant. Or even worse, delta I goes up and results in an exponential reduction in capacitor Z. A capacitor becomes a v .......
30: Tube DIY Asylum, RE: That explains some of the issues you saw (0.00)
Posted by JLH on 2011-02-12, 17:53:50 (76.252.5.82)
That looks pretty good to me. What I currently have serves me very well, so I'm not inclined to change it right now. In a future build, I do plan to try a larger inductance value for L2, but still kee .......
31: Tube DIY Asylum, That explains some of the issues you saw (0.00)
Posted by JLH on 2011-02-11, 17:40:42 (70.236.34.231)
The power supply you have pictured did not work very well for me either. We are in agreement on this part. However, the flywheel worked very well for me. It resulted in a better sonic result than the .......
32: Tube DIY Asylum, RE: Yes it is resonant - but not hash (0.00)
Posted by JLH on 2011-02-10, 18:35:34 (70.236.40.59)
"Disagree. All other things being equal, the higher the charging current to C1 the more noise is generated and the poorer the voltage regulation of the supply. So from a technical POV, higher charging .......
33: Tube DIY Asylum, RE: Yes it is resonant - but not hash (0.00)
Posted by JLH on 2011-02-10, 03:20:46 (69.174.58.44)
Tre, I'm not sure if the charge current matters much in this type of power supply. The over rated amp capacity and low DCR in the transformer secondary tames most of the undesirable things we normally .......
34: Tube DIY Asylum, Yes it is resonant - but not hash (0.00)
Posted by JLH on 2011-02-09, 13:23:44 (69.174.58.44)
Sean kindly searched and found one of my old posts here: http://db.audioasylum.com/cgi/m.mpl?forum=tubediy&n=133283&highlight=power+supply+JLH In the post I state that the Flywheel works best when th .......
35: Tube DIY Asylum, I've checked this in the past (0.00)
Posted by JLH on 2011-02-09, 04:50:37 (69.174.58.44)
I've looked at this in my own supplies with a scope and they don't exist. The spikes are more likely some kind of weird computational thing going on with PSUDII. Additionally, most people I know don't .......
36: Tube DIY Asylum, Graetz hybrid bridge - Email sent (nt) (0.00)
Posted by JLH on 2011-01-25, 04:16:01 (69.174.58.36)
. .......
37: Tube DIY Asylum, A NFL analogy for this forum (0.00)
Posted by JLH on 2011-01-19, 04:14:10 (69.174.58.36)
Time and time again there is a popular opinion that a certain team will surely beat another team. Loe and behold, an upsets occurs. Very much like the Jets had no chance to beat the Patriots. Guess wh .......
38: Tube DIY Asylum, Rectifiers (0.00)
Posted by JLH on 2011-01-16, 10:49:20 (69.174.58.44)
The 5U4 is a dual directly heater rectifier. The 6AU4 is a single damper diode, so you would need two of them to replace the 5U4. However, the 6BY5 is a dual damper diode that can take the place of th .......
39: High Efficiency Speaker Asylum, Yes, but... (0.00)
Posted by JLH on 2011-01-13, 04:53:10 (69.174.58.36)
The DCR will change and I like to cover everything when I go to that much trouble to tune something. I know its picky, but that how I like to roll. ;0) .......
40: High Efficiency Speaker Asylum, RE: 95 db mid driver 6-10 inch audiophile project? (0.00)
Posted by JLH on 2011-01-13, 04:50:52 (69.174.58.36)
What's with the attitude toward pro sound drivers? .......
41: High Efficiency Speaker Asylum, This is how you can make the new inductors work, (0.00)
Posted by JLH on 2011-01-12, 03:36:45 (69.174.58.44)
If most of the inductors are actually lower in value than what is shown in the schematic, then all you have to do is remove some turns of wire to get the same values as the originals. The best way wou .......
42: Tube DIY Asylum, PM sent (nt) (0.00)
Posted by JLH on 2011-01-10, 11:11:24 (69.174.58.36)
. .......
43: Tube DIY Asylum, RE: LCR versus RC in the RIAA (0.00)
Posted by JLH on 2011-01-07, 07:43:34 (69.174.58.36)
I searched and found it in the below link. .......
44: Tube DIY Asylum, RE: LCR versus RC in the RIAA (0.00)
Posted by JLH on 2011-01-05, 04:21:19 (69.174.58.36)
I use the 600 ohm Silk LCR modules and refuse to go back to RC filters. The main thing the LCR has over the RC in spades is realism. Everything is more natural and real sounding - never forced or arti .......
45: High Efficiency Speaker Asylum, Agreed! (nt) (0.00)
Posted by JLH on 2010-12-28, 06:27:31 (69.174.58.36)
. .......
46: Tube DIY Asylum, Do a search for Screen drive pentode (0.00)
Posted by JLH on 2010-12-16, 12:18:58 (76.252.48.220)
A lot has been written about this mode of operation. The main issues being high drive voltage requirements, and you have to supply screen grid current. Some have used cathode followers, but in my expe .......
47: Tube DIY Asylum, RE: Balancing (AC & DC) the CCS cascoded LTP phase splitter (0.00)
Posted by JLH on 2010-12-02, 04:24:28 (69.174.58.44)
Over on DIY Audio there was a 6L6GC amp build that used diodes and a pot on the first TLP to balance the DC on the second LTP. This helps both phases on the second LTP clip at the same time. The CC .......
48: Tube DIY Asylum, Huh? (0.00)
Posted by JLH on 2010-10-01, 20:36:07 (69.219.237.6)
I'm not following what you posted. Was this in reference to something that I've posted before? .......
49: Tube DIY Asylum, RE: Zero-Bias 5755 Phono Preamp (0.00)
Posted by JLH on 2010-09-21, 03:24:13 (69.174.58.36)
I built this LCR phono pre based off of Throsten's ideas. I tried zero bias on the first tube, but grid current was a problem. It would pop a lot and had some weird sounds. I had to add the 1.5 ohm ca .......
50: Tube DIY Asylum, Is that what your speakers require? (0.00)
Posted by JLH on 2010-09-14, 10:53:38 (69.174.58.44)
Over doing a power supply pays zero dividends. No blanket statements or rules of thumb. Make the speaker measurement and then perform the math. .......
51: Tube DIY Asylum, Do the math and find out (0.00)
Posted by JLH on 2010-09-14, 10:38:37 (69.174.58.44)
If you want to find out how much ripple you can tolerate all you have to do is perform the math. For example let us look at a 300B SE amp with a 3.5K opt. The 300B has an amplification factor of aroun .......
52: Tube DIY Asylum, Do the math and find out. (0.00)
Posted by JLH on 2010-09-14, 10:12:29 (69.174.58.36)
The DC resistance is part of the load and really doesn't matter. If you look at the Lundahl LL1667/15mA it has 270H and a DCR of 2.4K ohms. So at 20Hz your load becomes ((2*Pi*20Hz*200H)+ 2400 ohms) = .......
53: Tubes Asylum, Are those based off of the Russian 6N23P? (0.00)
Posted by JLH on 2010-09-04, 19:24:29 (70.236.68.124)
Just curious about where this tubes come from. Rgs, JLH .......
54: Tube DIY Asylum, Keep hating (0.00)
Posted by JLH on 2010-08-28, 08:43:05 (76.251.224.98)
You guys really like to hate new and free thinking. Once again you all sit in front of your computers trying to figure out a way to discredit something that none of you have ever built or listened to. .......
55: Tube DIY Asylum, Traditional power supplies are not very good (0.00)
Posted by JLH on 2010-08-18, 20:58:34 (70.236.78.211)
Conventional wisdom in regards to what is considered ideal engineering does not take into consideration the effect on the tubes. It is only concerned with specs and how “solid” the power supply appear .......
56: High Efficiency Speaker Asylum, What can you possibly disagree with? (0.00)
Posted by JLH on 2010-08-12, 12:41:01 (69.174.58.36)
Most of the discussion about Zu speakers has been on the Druid. Therefore my comments were in regards to it. What do you disagree with?: 1.) Zu is not well received. It is obvious even now that the Zu .......
57: High Efficiency Speaker Asylum, RE: Zu Essence (0.00)
Posted by JLH on 2010-08-09, 05:48:14 (69.174.58.36)
I would recommend you perform a forum search for Zu. You will find that Zu speakers are not well received on the forum. Their claim of 101 dB sensitivity from a box volume of less than 3 cu. ft. is la .......
58: K&K Audio / Lundahl Transformers, Tubelab Power drive would fix that ;0) (nt) (0.00)
Posted by JLH on 2010-06-10, 14:19:16 (76.240.222.83)
. .......
59: K&K Audio / Lundahl Transformers, SOLD (0.00)
Posted by JLH on 2010-05-18, 06:13:12 (69.174.58.44)
SOLD .......
60: K&K Audio / Lundahl Transformers, RE: FS: LL1654/30mA and LL1667/15mA (0.00)
Posted by JLH on 2010-05-17, 09:17:04 (69.174.58.44)
I have replied via e-mail. Thanks! Rgs, JLH .......
61: K&K Audio / Lundahl Transformers, FS: LL1654/30mA and LL1667/15mA (0.00)
Posted by JLH on 2010-05-15, 18:58:46 (76.252.4.8)
With Kevin's permission I have two sets of Lundahl iron to sell. The first is a pair of line output transformers. They are LL1654/30mA. They are 5K:600 or 5K:150. Turns ratios are 2.88:1 or 5.77:1. Si .......
62: Tube DIY Asylum, I would recommend the KOA Speer carbon film instead (0.00)
Posted by JLH on 2010-05-12, 04:31:47 (69.174.58.44)
The new carbon film resistors from KOA Speer are excellent. They do not suffer from many of the problems of the carbon composition resistors. They can give a very similar sound to carbon composition r .......
63: Tube DIY Asylum, Yes, do as Chris says. (0.00)
Posted by JLH on 2010-05-10, 18:58:40 (76.251.248.20)
Get all your components and lay them out. This will tell you what size to use. .......
64: Tube DIY Asylum, 100% (0.00)
Posted by JLH on 2010-04-20, 05:03:26 (69.174.58.36)
Show me where your output tube is in that simulation. What! No wait, PSUDII doesn't take into account the output tube and the affects the power supply will have on it. You have the wrong tool for the .......
65: Tube DIY Asylum, Since when has a capacitor been classified as a voltage source? (nt) (0.00)
Posted by JLH on 2010-04-20, 04:59:49 (69.174.58.36)
. .......
66: Tube DIY Asylum, You can't have both ways - Either caps are low impedance or they're not. (0.00)
Posted by JLH on 2010-04-20, 04:57:27 (69.174.58.36)
People can see right through your attempts at trying to bend the truth to fit your out dated ideological model. Capacitors are low impedance devices and will always compete with the output tube for cu .......
67: Tube DIY Asylum, You’re neglecting the behavior of capacitors. (0.00)
Posted by JLH on 2010-04-16, 05:50:50 (69.174.58.36)
In all our engineering books we are taught that a high capacitance power supply is good. The authors imply that the low impedance of the capacitor will be able to deliver current to the output tube qu .......
68: Water Cooler, I had both, but chose a more responsible path. (0.00)
Posted by JLH on 2010-03-23, 08:14:07 (69.174.58.36)
Number 1 you don't know me or my finances. Through I will share some of the info with you. I keep 4 - 6 months worth of expenses in savings and my credit score has always been above 700. It was the bi .......
69: Water Cooler, I've been there. (0.00)
Posted by JLH on 2010-03-22, 12:39:38 (69.174.58.36)
My wife broke her ankle and it ended up costing us $6000 in medical fees. We called up the medical billing office and set up an affordable monthly payment program with them. It was all paid for as of .......
70: Water Cooler, And who do you think will end up paying for this? (0.00)
Posted by JLH on 2010-03-22, 09:46:17 (69.174.58.36)
Those of us that get up and go to work every day and pay our taxes like a good little Americans will get taxes from all directions. I'm so tired of being taxed so lazy fucks can free load on my back. .......
71: Water Cooler, Goody, I get to work harder so someone else can sit on their butt. (0.00)
Posted by JLH on 2010-03-22, 03:32:17 (69.174.58.36)
Government cannot give to someone without first taking from another. There will be Hell to pay in November. .......
72: High Efficiency Speaker Asylum, You are correct Sir. (nt) (0.00)
Posted by JLH on 2010-03-14, 11:12:42 (69.174.58.44)
nt .......
73: High Efficiency Speaker Asylum, No not really (0.00)
Posted by JLH on 2010-03-13, 09:04:26 (76.251.241.8)
The closest you'll get is simulating the horns in Horn Response and trying to match the phase predicted by the software. The other option is to feed both horns from a function generator in opposite po .......
74: High Efficiency Speaker Asylum, Its not that simple (0.00)
Posted by JLH on 2010-03-12, 17:53:56 (76.252.32.248)
Physical time alignment goes out the window once you put a crossover in place. A 2nd order Linkwitz-Riley filter has a 180 degree phase difference between the high pass and low pass. With a 200Hz cros .......
75: K&K Audio / Lundahl Transformers, That should make for a nice winter time space heater ;0) (0.00)
Posted by JLH on 2010-03-02, 05:51:13 (69.174.58.44)
NT .......
76: Tube DIY Asylum, I'll teach you how to fish (0.00)
Posted by JLH on 2010-03-02, 05:47:31 (69.174.58.44)
I’ll calculate Vlaw and Vfac for a 5U4 tube with both its sections in parallel at 150mA (75mA per section). Look up the data sheet for the tube you want. You’ll need the data sheet to have the voltage .......
77: MagneQuest/Peerless Forum, Interesting test report (0.00)
Posted by JLH on 2010-02-24, 20:08:42 (70.236.66.138)
Since Mikey's transformers are in a different class (higher) I don't think pointing to this test report will do any harm. It does provide some interesting testing results. The lamination I'm the most .......
78: K&K Audio / Lundahl Transformers, Is it cost effective to send chokes/transformers back for re-gapping? (0.00)
Posted by JLH on 2010-02-24, 06:48:33 (69.174.58.36)
Kevin, I have some Lundahl iron lying around that I’d like to use for a different project. I have a pair of LL1667/15mA that I actually would like to use as grid chokes. Over at Jac Music they are .......
79: Tube DIY Asylum, RE: Ripple Step Down by Output Transformers (0.00)
Posted by JLH on 2010-02-15, 15:23:07 (76.251.232.131)
A transformer will step down the ripple present on it's primary winding by the turns ratio. To calculate the turns ratio you divide the primary impedance by the secondary impedance and then take the s .......
80: Tube DIY Asylum, I second Electra-Print (0.00)
Posted by JLH on 2010-02-13, 19:00:04 (76.252.60.187)
Jack will make anything you want. It will also be excellent quality. Rgs, JLH .......
81: Tube DIY Asylum, Interstage split choke (0.00)
Posted by JLH on 2010-02-06, 13:31:51 (76.251.241.147)
You can use a Lundahl LL1667/5mA from forum sponsor Kevin with K&K Audio. The standard model is gapped for 15mA of unbalanced current. Since the plate current from each triode will cancel this offset, .......
82: Tube DIY Asylum, I sent you a message. (nt) (0.00)
Posted by JLH on 2010-02-05, 13:15:35 (69.174.58.44)
. .......
83: Tube DIY Asylum, Dampening factor applies to more than just speakers (nt) (0.00)
Posted by JLH on 2010-02-03, 12:31:24 (69.174.58.36)
. .......
84: Tube DIY Asylum, RE: AVC newby considering trying it...suggestions welcome (0.00)
Posted by JLH on 2010-02-03, 03:52:39 (69.174.58.36)
With resistive volume controls your output impedance increases as you turn the volume down. The series resistive element increases in value, and the shunt element decreases. This has the effect of red .......
85: Tube DIY Asylum, The Alpine house sound = etched and thin (0.00)
Posted by JLH on 2010-02-03, 03:44:54 (69.174.58.36)
I don't know about the sound of the Luxman before Alpine ownership. However, I can tell you the post Alpine owned Luxman products all share the same house sound. This signature was also present in the .......
86: Book Boulevard, I just could not get into this "classic". :( (0.00)
Posted by JLH on 2010-01-26, 06:09:14 (69.174.58.36)
I tried to like it, but it was too slow a read and keeping track of all the names was distracting to me. I got through 65% of it, laid it down and never picked it up again. .......
87: Book Boulevard, Recommendation ---) Christopher McDougall – Born to Run (0.00)
Posted by JLH on 2010-01-26, 06:03:16 (69.174.58.36)
This book is for anyone that is or has been a runner or just enjoys sports related books. It is a fantastic look inside the realm of ultra marathons and the answer to why some people are constantly in .......
88: High Efficiency Speaker Asylum, Incorrect... (0.00)
Posted by JLH on 2010-01-20, 06:16:29 (69.174.58.36)
The battery is tied between two capacitors and a high value resistor therefore there is no direct current path for the battery to discharge. The capacitors block DC current and the high value resistor .......
89: Tube DIY Asylum, If you want the sound of thoriated tungsten filaments use an 801A... (0.00)
Posted by JLH on 2010-01-17, 05:35:17 (69.174.58.44)
You have Altec model 19's, so 4 watts from a nice 801A amp should be enough. Why mess around with big transmitting tubes that burn up more watts in the filament than what you can get out of them? High .......
90: Tube DIY Asylum, That's what you'll be saying when they corner you in the shower... (0.00)
Posted by JLH on 2010-01-13, 07:52:29 (69.174.58.36)
Sorry Naz, I couldn't resist ;0) .......
91: Tube DIY Asylum, IXTP01N100D is reported as better than 10M45S (0.00)
Posted by JLH on 2010-01-08, 04:21:11 (69.174.58.44)
They guys over at K&K Audio found it to sound better. .......
92: High Efficiency Speaker Asylum, Ask Allen Wright his opinion on oil caps. (0.00)
Posted by JLH on 2009-12-29, 05:57:51 (69.174.113.20)
He will give you an ear full of why he does NOT use them. Stay with nice film or foil caps. .......
93: High Efficiency Speaker Asylum, It is not always necessary to physically align the voice coils (0.00)
Posted by JLH on 2009-12-20, 06:33:39 (69.174.113.20)
If you are using passive crossovers, then you will NOT end up with the voice coils at the same positions. The reason for this is the phase lag the low pass crossover creates. In order to phase align t .......
94: Tube DIY Asylum, Use the Wayback Machine to view it. (0.00)
Posted by JLH on 2009-12-18, 19:13:36 (70.225.133.138)
See link Rgs, JLH .......
95: High Efficiency Speaker Asylum, RE: Not that expensive or difficult to do. (0.00)
Posted by JLH on 2009-12-09, 11:26:55 (69.174.113.20)
I put too much research and development into that phasing plug. I'm not really willing to release it into the free domain of the internet at this time. As you recall I did share the very begining of t .......
96: High Efficiency Speaker Asylum, RE: Pillow block bearings (0.00)
Posted by JLH on 2009-12-09, 07:16:07 (69.174.113.20)
I had a machine shop make one for me. The small pulley is attached to the lathe's stock spindle. The support spindle is 1 3/4" in daimeter. It is turned down to 1" diameter at the back for the 1" pill .......
97: High Efficiency Speaker Asylum, Pillow block bearings (0.00)
Posted by JLH on 2009-12-09, 07:03:34 (69.174.113.20)
I use a 1" on the back of the support shaft, and a 1 3/4" at the face plate. The 1 3/4" pillow block bearing is rated at 5000 lbs, so a tiny 180 lb horn can't hurt it. :0) .......
98: High Efficiency Speaker Asylum, Not that expensive or difficult to do. (0.00)
Posted by JLH on 2009-12-09, 06:52:27 (69.174.113.20)
I think I have $400 invested in my lathe setup. It is just a 1/2 HP Sears lathe with a 3:1 reduction pulley system. I bought the lathe for $300. I bought the pillow bearing from Wholesale Tool for abo .......
99: Tube DIY Asylum, No, it is all made in China now. (nt) (0.00)
Posted by JLH on 2009-12-04, 07:43:31 (69.174.113.20)
. .......
100: Tubes Asylum, The circuit. (nt) (0.00)
Posted by JLH on 2009-12-04, 07:42:31 (69.174.113.20)
. .......
101: Tube DIY Asylum, Is that a Sowter output transformer? (0.00)
Posted by JLH on 2009-11-19, 06:13:20 (69.174.58.44)
Those Peerless output transformers look like they are from Sowter. You did a great job on your build. When you get a chance I think everyone here would like to see the schematic you followed. I'm very .......
102: High Efficiency Speaker Asylum, Ditto... (0.00)
Posted by JLH on 2009-11-18, 03:59:17 (69.174.58.36)
I've seen it several times. People try a single driver and think they have found the Holy Grail. Soon, after all the newness wears off they start to identify all the holes in their performance. I thin .......
103: High Efficiency Speaker Asylum, RE: TAD 4002 crossover advice (0.00)
Posted by JLH on 2009-11-05, 05:56:43 (40.0.40.10)
If you are using a TAD exponential horn or TAD clone you are better off staying with a resistive L-pad. That horn was designed and voiced with heavy resistive padding to mate to a direct radiator. Thi .......
104: Tubes Asylum, RE: Western Electric 300B-gone for ever? (0.00)
Posted by JLH on 2009-11-01, 16:05:51 (76.251.224.184)
I like the Emissions Labs 300B-XLS as a good good replacement for the WE300B. It does require a little bit more filament current, but is cleaner in the mids and more solid in the bass than the WE300B. .......
105: High Efficiency Speaker Asylum, RE: Altec vs TAD 2001 drivers (0.00)
Posted by JLH on 2009-10-31, 06:07:53 (40.0.40.10)
You can use a number of different horns or waveguides. A 800Hz round tractrix horn will load down to your desired 1250Hz point. You could also try any of the current conical type waveguides or the obl .......
106: High Efficiency Speaker Asylum, RE: Altec vs TAD 2001 drivers (0.00)
Posted by JLH on 2009-10-30, 10:14:35 (40.0.40.10)
Changing to a more netural sounding horn will make a larger improvement in sound than buying expensive TAD drivers. The TAD TD-2001 is a nice driver, but is over valued IMO. I have found that the horn .......
107: High Efficiency Speaker Asylum, Just a typo on my behalf. (0.00)
Posted by JLH on 2009-09-27, 17:26:28 (76.251.232.84)
I meant to type an "8" in there, but some how a "4" ended up in there. Rgs, JLH .......
108: High Efficiency Speaker Asylum, Definition of high efficiency approx. 96dB 1W/1M (0.00)
Posted by JLH on 2009-09-26, 15:52:52 (76.252.12.10)
If you consider the 300B the standard high efficiency speaker amplifier, then 96dB 1W/1M is about right. We arrive at this by having 75dB as the average sound level at the listening position. Then fig .......
109: High Efficiency Speaker Asylum, Some links for you (0.00)
Posted by JLH on 2009-09-23, 03:14:42 (40.0.40.10)
There are several manufacturers that make good coax drivers. One good example is the B&C Speakers 8CX21. I do believe this is the driver that Danley Sound Labs uses in their SH-100. See below links fo .......
110: High Efficiency Speaker Asylum, What Don said - show us this "perfect" driver. (0.00)
Posted by JLH on 2009-09-23, 03:01:59 (40.0.40.10)
I don't believe that anyone on this forum is aware of a single driver that can cover the generally excepted audiophile standard of 20Hz to 20KHz without help on one end or the other. (FYI - my persona .......
111: High Efficiency Speaker Asylum, Ummm...This is the High Efficiency Speaker Asylum. (0.00)
Posted by JLH on 2009-09-21, 13:48:15 (99.10.113.79)
The Jordan is not high efficiency. Rgs, JLH .......
112: MagneQuest/Peerless Forum, If it was me, I'd do this. (0.00)
Posted by JLH on 2009-09-16, 09:25:10 (40.0.40.10)
I think this is a well thought out project. Any parts that are not really required are removed and the parts that are there, perform more than one function. I have not heard this unit, but can't imagi .......
113: Tubes Asylum, I second the JJ 300B's. (0.00)
Posted by JLH on 2009-09-12, 11:25:13 (99.10.104.4)
The JJ's I've ran in the past out lived my Svetlana 300B's. I felt like the Svetlanas had more of that euphoric midrange, but the JJ's had more extended bass and treble. YMMV. Rgs, JLH .......
114: Tubes Asylum, How much cathode feedback in the OPT? (0.00)
Posted by JLH on 2009-09-01, 04:13:53 (40.0.40.10)
I see your OPT has a CFB winding. It is rare to see CFB with triodes. I have used CFB with pentodes, but never with triodes. Who made the OPTs for you? Rgs, JLH .......
115: High Efficiency Speaker Asylum, Don't worry Tom. (0.00)
Posted by JLH on 2009-07-24, 02:57:12 (40.0.40.10)
Any logical statements made in that forum are considered insubordination. ;0) .......
116: High Efficiency Speaker Asylum, RE: Community M-200 drivers (0.00)
Posted by JLH on 2009-07-10, 03:16:25 (40.0.40.10)
Since the M200 is a mid range only driver, I'm assuming you are talking about the BMS 4592-MID and not the 4592ND model. The M200 does not have a real phasing plug per se, while the 4592-MID does. Due .......
117: High Efficiency Speaker Asylum, I hate you ;o) (0.00)
Posted by JLH on 2009-07-10, 02:58:56 (40.0.40.10)
No, not really. I'll never hate anyone for making a great save like that. Consider yourself very lucky. Looks like you got some very nice pieces there. Best of luck. Rgs, JLH .......
118: Tube DIY Asylum, It’s not about averages, it about instantaneous. (nt) (0.00)
Posted by JLH on 2009-07-02, 12:21:50 (40.0.40.10)
. .......
119: Tube DIY Asylum, Dynamic impedance explained (0.00)
Posted by JLH on 2009-07-01, 04:36:38 (40.0.40.10)
Tre and Testing123, Your assumption that a Class A amplifier would only undergo 10% change in current is greatly under estimated. Everyone knows, or is told that Class A has a constant current draw. T .......
120: Tube DIY Asylum, Power transformer DCR sets the dynamic impedance. (0.00)
Posted by JLH on 2009-06-30, 04:23:03 (40.0.40.10)
Most folks on this forum understand that there is a balance to everything. Most also know that copper losses are not the only factor in power transformer and choke design. While I have seen chokes des .......
121: SET Asylum, RE: anyone here have a SET with Lundahl amorphous outputs? (0.00)
Posted by JLH on 2009-06-05, 15:08:52 (70.236.2.48)
Single ended series feed is not the best place to deploy amorphous cored transformers. I have heard the LL1623 iron vs. LL1623 amorphous and honestly there wasn’t much difference. They sounded slightl .......
122: High Efficiency Speaker Asylum, RE: Nope, but.... (0.00)
Posted by JLH on 2009-06-03, 03:10:32 (40.0.40.10)
I've used it both ways. I designed a radial phasing plug for it. The plug has a 2.5" exit. Sound is excellent from 300Hz to 3KHz on 205Hz tractrix. Biggest challeng is getting the back chamber small e .......
123: Tube DIY Asylum, RE: KOA Speer 2W carbon films (0.00)
Posted by JLH on 2009-06-02, 18:44:49 (69.208.152.125)
I've used them in a new build LCR phono stage, and to upgrade an exsisting power amp. I like them very much. Its a nice resistor that I can't really fault. Rgs, JLH .......
124: High Efficiency Speaker Asylum, Nope, but.... (0.00)
Posted by JLH on 2009-06-02, 18:35:51 (69.208.152.125)
I eneded up with Faital Pro M5N12-80. This is a very nice high efficiency 5" that is a lot easier to obtain than the JBL. I haven't looked back. Rgs, JLH .......
125: K&K Audio / Lundahl Transformers, It depends on the tube used (0.00)
Posted by JLH on 2009-05-07, 10:00:10 (40.0.40.10)
It depends on the tube used. High Gm tubes respond more to small amounts of CFB. Low Mu and Rp tubes do not respond much because they already have a lot of internal feedback built into their design. E .......
126: K&K Audio / Lundahl Transformers, I do not agree (0.00)
Posted by JLH on 2009-05-04, 11:20:46 (40.0.40.10)
I will have to disagree with who ever told you that CFB sounds anything like global feedback. I have built two different CFB amps and they sound nothing like a classical global feedback amplifier. If .......
127: Tube DIY Asylum, Check out Eletra-Print (0.00)
Posted by JLH on 2009-05-03, 17:51:55 (68.78.6.94)
Look at the PVA-2n and the A2LD-7 transformers. Also look at the schematic section which has two Class A2 amps using those opamp transformers. Rgs, JLH .......
128: High Efficiency Speaker Asylum, 90dB with a stiff tailwind, maybe!!!! (0.00)
Posted by JLH on 2009-04-24, 09:19:02 (69.208.153.141)
I'm glad you seem to like them. The last time I listened to ML speakers it was with a 200W Adcom GFA-555 power amplifier. We clipped the amplifier without even trying. On the other hand, my horns with .......
129: Tube DIY Asylum, The primary inductance is very low on those. (0.00)
Posted by JLH on 2009-04-09, 03:20:09 (40.0.40.10)
Mikey can give you all the technical reasons for good primary inductance. The problem I see with the RW-20 OPTs is the max inductance is only 13H. This will result in a -3dB point of about 60Hz for a .......
130: High Efficiency Speaker Asylum, This is how I do it. (0.00)
Posted by JLH on 2009-03-25, 17:28:00 (70.236.10.146)
http://www.diyaudio.com/forums/showthread.php?postid=1668555#post1668555 http://www.diyaudio.com/forums/showthread.php?postid=1508370#post1508370 .......
131: Tube DIY Asylum, Why the 6C45Pi tube? (0.00)
Posted by JLH on 2009-03-19, 17:12:49 (69.208.156.100)
I have a personal hatred for the 6C45Pi tube. Most of the people I know that use it because of its specs. Its specs look good on paper; too bad it is sonic trash to the ears. .......
132: SET Asylum, RE: Which Grid Choke? (0.00)
Posted by JLH on 2009-03-16, 13:04:11 (69.208.154.188)
Your supposed to design your circuit such that no DC current will flow through the grid choke. You either need a cap coupled or transformer coupled driver stage. AC current will not bother the grid ch .......
133: High Efficiency Speaker Asylum, RE: Tall order (0.00)
Posted by JLH on 2009-03-01, 16:13:28 (68.78.6.217)
Mouth area will determine how much ripple you have down to the cutoff frequency. For 200Hz in free space you’ll need about 362 sq. inch mouth. That’s not too big in my book. If you place the horn on t .......
134: High Efficiency Speaker Asylum, RE: mid-bass horn design help please (0.00)
Posted by JLH on 2009-02-28, 22:01:22 (69.208.150.52)
Unfortunately the EV10M will not fit in the back chamber of those horns. The EV10M has an overall diameter of 10.23” and the back chamber diameter on those horns is 9.75”. While the specs don’t look l .......
135: High Efficiency Speaker Asylum, Tall order (0.00)
Posted by JLH on 2009-02-28, 21:35:01 (69.208.150.52)
You are asking for a very tall order. There are very few ways you are going to get a EVM10M to reach 1.2KHz. First, the largest throat size can’t be any more than about 10 sq. inches. If you make it a .......
136: High Efficiency Speaker Asylum, Atc should not be more than 2 X Sd in your case (0.00)
Posted by JLH on 2009-02-20, 03:04:13 (40.0.40.10)
The area (Atc) you have allowable in your design from my understanding is the combined Sd of the woofers. You should also rethink your Vtc input parameter. No software program is useful unless you inp .......
137: High Efficiency Speaker Asylum, Peter your input parameter are not correct. (0.00)
Posted by JLH on 2009-01-28, 17:06:31 (69.208.158.70)
You really need to account for the output impedance of your amplifier. If you are using solid state, then 0.4 ohm for the Rg field seems to be about right. For tube amplifiers it will need to be close .......
138: High Efficiency Speaker Asylum, Both of you guys are right in your own way (0.00)
Posted by JLH on 2009-01-28, 04:49:58 (40.0.40.10)
Both the Fane and B&C are good horn drivers. Each one will sound different and depending on what you want from it will determine which is best for "You". There is no absolute answer for everyone. Rgs, .......
139: High Efficiency Speaker Asylum, This is how I do it. (0.00)
Posted by JLH on 2009-01-28, 04:42:43 (40.0.40.10)
This is what I do. I run my simulation in Hornresp. I then do a screen capture by holding down the "Ctrl" key and pressing the "Print Scrn" key. I then open Microsoft Paint. Once open, you can right c .......
140: High Efficiency Speaker Asylum, RE: BEST cone driver for specific conical horn? (0.00)
Posted by JLH on 2009-01-28, 04:25:56 (40.0.40.10)
The P Audio driver looks ideal for your application. It has a nice rising response as frequency increases. The horn loading will bring up the lower frequencies and should result in a pretty even frequ .......
141: High Efficiency Speaker Asylum, You are correct. (nt) (0.00)
Posted by JLH on 2009-01-28, 04:20:56 (40.0.40.10)
. .......
142: High Efficiency Speaker Asylum, RE: BEST cone driver for specific conical horn? (0.00)
Posted by JLH on 2009-01-27, 03:22:09 (40.0.40.10)
If you are looking for a clean and clear sound then you have to do something about interface between the horn throat and the woofer. When your throat opening is smaller than the cone, you get a lot of .......
143: Tube DIY Asylum, You guys are making too many assumptions. More info needed! (0.00)
Posted by JLH on 2008-12-04, 05:43:19 (40.0.40.10)
Before you make blanket statements about which direction of the transformer has the most magnetic radiation you have to look at the physical construction of the transformer. The coil winding can be ve .......
144: Vinyl Asylum, Herbie Hancock - Future Shock (nt) (0.00)
Posted by JLH on 2008-11-29, 05:56:57 (40.0.40.10)
. .......
145: Tube DIY Asylum, RE: If you're building, this might interest you. (0.00)
Posted by JLH on 2008-11-19, 12:18:11 (70.236.5.49)
The amount of power transfer a TVC or AVC has is simple mathematics. We know that maximum power transfer occurs when the source impedance equals the load impedance. When the source impedance is signif .......
146: Tube DIY Asylum, If you're building, this might interest you. (0.00)
Posted by JLH on 2008-11-19, 08:40:48 (70.236.5.49)
There are several concepts that people build along. I'm not knocking anybody's style, but I think this guy has some very good points. Below is a quote and link. "Back to the Espressivo, it is interest .......
147: High Efficiency Speaker Asylum, Replied via private e-mail (nt) (0.00)
Posted by JLH on 2008-10-29, 22:45:57 (70.227.31.175)
. .......
148: High Efficiency Speaker Asylum, No, the Colts are their own worst enemy, Ha! (0.00)
Posted by JLH on 2008-10-25, 15:32:13 (69.208.157.163)
This up coming Monday Night Football game is going to be ugly for the Colts. You can't win without some good "D". Good to hear from you again. Rgs, JLH .......
149: High Efficiency Speaker Asylum, Replied via private e-mail (nt) (0.00)
Posted by JLH on 2008-10-23, 16:43:29 (69.208.149.45)
. .......
150: High Efficiency Speaker Asylum, Going back to the drawing board (0.00)
Posted by JLH on 2008-10-23, 09:56:07 (69.208.149.45)
In another post below you asked about 8” woofers that would be suitable for horn loading. So, I’m guessing you are after a front loaded horn with a 200mm throat that uses an 8” woofer good for 150Hz t .......
151: High Efficiency Speaker Asylum, You need to be more specific (0.00)
Posted by JLH on 2008-10-22, 14:53:39 (70.229.31.63)
A general question receives general answers that lead to generally bad designs. What exactly are the goals for this horn? What is the desired bandwidth? Sensitivity? Power handling? What are the bound .......
152: High Efficiency Speaker Asylum, If you knew how much work is involved... (0.00)
Posted by JLH on 2008-10-17, 03:28:00 (40.0.40.10)
You would not be complaining about that price. I wouldn’t even think about firing up my lathe for anything less than a couple grand or more $$$$. If you want to play, then be prepared to pay if you ca .......
153: Tube DIY Asylum, I agree! (nt) (0.00)
Posted by JLH on 2008-10-12, 18:12:25 (70.229.27.214)
. .......
154: Tube DIY Asylum, The lowest distortion driver does not always yield the lowest overall distortion (0.00)
Posted by JLH on 2008-10-11, 18:03:28 (68.78.7.201)
If any of you guys have the old issues of Glass Audio go look at the 1996 volume 8, issue number 4. There is a very nice article by Reid Welch on harmonic cancellation. His circuit consisted of a 417A .......
155: SET Asylum, Probably a little Class A2 action going on there. (nt) (0.00)
Posted by JLH on 2008-10-07, 06:41:28 (40.0.40.10)
. .......
156: Tube DIY Asylum, Making clueless assumptions again – I’m the one doing the laughing. (0.00)
Posted by JLH on 2008-10-06, 11:16:37 (40.0.40.10)
I’ll explain this only once and will not be responding to any follow-up questions. If you are unable to understand my engineering choices, reasons, or just flat out disagree with them that’s too bad. .......
157: Tube DIY Asylum, This is how you fix the "minimum threshold" error (0.00)
Posted by JLH on 2008-09-30, 09:35:54 (70.236.7.192)
Open PSUDII and click on the "Options" drop down menu. Go to "Rectifer Leak" and select "10K". This will get rid of the threshold error problem. .......
158: Tube DIY Asylum, Triode wired 2E24 or 46 (nt) (0.00)
Posted by JLH on 2008-09-30, 09:30:42 (70.236.7.192)
. .......
159: Tube DIY Asylum, Charge current waveform (0.00)
Posted by JLH on 2008-09-30, 09:27:05 (70.236.7.192)
Hi Tre, I want to make sure are talking about the same thing here. There are a few things that we are taught to object to in regards to non-continuous conduction. I know one objection is the actual ch .......
160: Tube DIY Asylum, Why must continuous conduction sound better? (0.00)
Posted by JLH on 2008-09-29, 22:45:17 (70.236.13.120)
Let’s entertain ourselves just for a minute. Of course anyone who has had higher education training in electronics knows the books state that continuous conduction is ideal. The books will also list a .......
161: Tube DIY Asylum, Boris - try this for me (0.00)
Posted by JLH on 2008-09-29, 16:31:12 (70.236.13.120)
Model the L-SES power supply with a Triad C-56U choke and 15uF capacitor right off the solid state rectifiers. The C-56U is 35mH @ 2A with a DCR of 0.79 ohms. You will now have a LCLCLC power supply. .......
162: SET Asylum, Apparently I was misinformed (0.00)
Posted by JLH on 2008-09-28, 18:57:25 (70.229.26.234)
I did some research and made a few phone calls. I guess this is what I get for listening to the local Hi-Fi store personnel. I’m not so stubborn that I can’t admit to my mistakes. .......
163: SET Asylum, The JJ 2A3-40 does NOT have a folded 5V filament. (0.00)
Posted by JLH on 2008-09-26, 11:48:30 (70.236.9.146)
The JJ 2A3-40 has a proper 2.5V filament. .......
164: Tube DIY Asylum, It tells you how much spin the tube’s electrons have. ;0) (0.00)
Posted by JLH on 2008-09-25, 23:01:30 (70.236.18.11)
Just kidding .......
165: Tube DIY Asylum, More details. (0.00)
Posted by JLH on 2008-09-19, 10:14:01 (40.0.40.10)
Not to insert myself into the discussion here, but since I was mentioned by name I thought I might provide some more info. There are some interesting details about the “Low-fi” choke(s) I’m using in t .......
166: Tube DIY Asylum, RE: LCR RIAA preamp (0.00)
Posted by JLH on 2008-09-17, 10:20:29 (68.78.6.51)
I tried a Jensen copper in oil cap, but it poured syrup all over my music. ;0) The silver mica cap was the most transparent to my ears. You can try what ever cap you want to. T and me just happened to .......
167: Tube DIY Asylum, RE: LCR RIAA preamp (0.00)
Posted by JLH on 2008-09-16, 19:20:13 (70.236.10.54)
Hi Jeff, The power transformer is a 145VAC X 2 (each winding DCR = 18 ohm) toroidal rated at 150VA. Each winding is rated for 500mA. I parallel the windings to make a single 145VAC rated for 1 Amp .......
168: Tube DIY Asylum, The LCR schematic in question (0.00)
Posted by JLH on 2008-09-16, 18:33:42 (70.236.10.54)
The caps values don't get anymore standard than 4.7uF and 0.12uF and there is only one DC path that needs blocked. I could have used a 1:1 bridging transformer instead of the 0.1uF, but felt like I al .......
169: Tube DIY Asylum, RE: LCR RIAA preamp (0.00)
Posted by JLH on 2008-09-16, 18:27:49 (70.236.10.54)
I don't see a problem with that. Why not? Heck, I would even try it if I wasn't already satified with my current unit. .......
170: Tube DIY Asylum, Reasons for 600 ohm (0.00)
Posted by JLH on 2008-09-16, 10:36:33 (40.0.40.10)
There are several reasons for the 600 ohm impedance. First it is the broadcasting standard impedance. Secondly, the inductor values required for the 10K units are more susceptible to impedance changes .......
171: Tube DIY Asylum, Not what you think. (0.00)
Posted by JLH on 2008-09-16, 10:31:47 (40.0.40.10)
Current does not pass through the coils because this is the tango modified version that only has caps to ground. The only DC path is blocked by the 0.1uF cap. It sounds better by letting the first sta .......
172: Tube DIY Asylum, RE: LCR RIAA preamp (0.00)
Posted by JLH on 2008-09-15, 20:41:59 (70.229.27.214)
This has beat every other phono preamp I've ever built. I am done fooling with other circuits. Its that good in my opinion. .......
173: High Efficiency Speaker Asylum, Wow! what a deal on JBL 375 drivers - Not! (0.00)
Posted by JLH on 2008-09-13, 10:43:42 (40.0.40.10)
That sure is some deal for JBL 375 drivers with shorted voice coils. Only if had $3600 stuffed under my mattress. .......
174: Tube DIY Asylum, You need to put things into perspective here. (0.00)
Posted by JLH on 2008-09-03, 18:50:58 (70.236.20.45)
The subjective loudness difference between getting 2.5W verses 3.5W out of an amplifier is only 1.46dB. Now the dB is considered lowest perceivable loudness difference that the “average” human ear can .......
175: High Efficiency Speaker Asylum, Details of your mid-bass horn please!(nt) (0.00)
Posted by JLH on 2008-09-03, 18:21:46 (70.236.20.45)
, .......
176: High Efficiency Speaker Asylum, Druids are worth about $0.02 (0.00)
Posted by JLH on 2008-08-29, 17:36:03 (68.78.6.98)
If some one gave me a pair I would sell the drivers on E-bay and use the enclosures for fire wood. At least they would have served some kind of useful purpose then. .......
177: High Efficiency Speaker Asylum, The good old days of auto sound (0.00)
Posted by JLH on 2008-08-24, 21:23:08 (69.208.152.92)
Yeah, I got some very strange looks back then. As you know very few car audio guys knew about compression drivers and horns. There was very little understanding about driver efficiency and SPL. I comp .......
178: High Efficiency Speaker Asylum, I'm not the expert on whizzer cones. (0.00)
Posted by JLH on 2008-08-24, 16:22:23 (69.208.152.92)
To me there are too many variables for me to keep track of. Your best bet is to contact the various manufacturers and see if they can teach us something about whizzer cones. Other than knowing they ex .......
179: High Efficiency Speaker Asylum, RE: That's nice but... (0.00)
Posted by JLH on 2008-08-24, 02:02:29 (69.208.151.173)
The failures you talk about were from uneducated people running the amps down to 0.25 ohm load in the high power mode. Any product can be considered unreliable if used incorrectly. I never said the So .......
180: High Efficiency Speaker Asylum, That's nice but... (0.00)
Posted by JLH on 2008-08-23, 18:56:57 (69.208.151.173)
I'm not talking about the current trash that has Soundstream written all over it. The real Soundstream was sold many years ago. I'm talking about the old Class A and Reference series that Eric Holdawa .......
181: High Efficiency Speaker Asylum, They are modified Lowther speakers (0.00)
Posted by JLH on 2008-08-23, 18:36:07 (69.208.151.173)
They replace the whizzer cone with a dual whizzer that has a rolled edge and some phasing holes punched in the sides. They don't sound like normal Lowther speakers at all. Rgs, JLH .......
182: High Efficiency Speaker Asylum, Forget TAD for cars - do this instead (0.00)
Posted by JLH on 2008-08-22, 02:54:14 (40.0.40.10)
For a high SQ front end contact Image Dynamics and get a pair of their Full Body sized wave guides without the drivers. Then order some BMS 4540ND compression drivers for them. Use a B&C Speakers 6NDL .......
183: Tube DIY Asylum, Tall order (0.00)
Posted by JLH on 2008-08-15, 19:42:08 (69.208.155.9)
Like others have mentioned, 150W triode power is not the easiest thing to do as a first project. You will end up spending at least $3K-$5K on them. The best route would be to use large transmitting tr .......
184: High Efficiency Speaker Asylum, The biggest problem with the Karlson is... (0.00)
Posted by JLH on 2008-07-05, 20:02:56 (70.236.2.74)
There is nothing to model one with. Or at least that I am aware of. The specs to an ideal woofer are also not well defined or documented. I'm not going to make saw dust without knowing something about .......
185: High Efficiency Speaker Asylum, Which set of plans do you have? (0.00)
Posted by JLH on 2008-06-16, 16:20:27 (70.236.4.66)
The original design, as pictured is a better performer than the more frequently seen "W" design. The bass is stronger on the original design. The original design information can be found here http://w .......
186: DIY HiFi Forum, Did you measure... (0.00)
Posted by JLH on 2008-06-16, 04:06:49 (40.0.40.10)
Hi Brian, Did you measure the inductance? What was the output impedance of your driving source? The frequency plots don't mean much without this information. Thanks for the information you have pro .......
187: SET Asylum, XSE25-8-5K is approx 18H at 50mA. (nt) (0.00)
Posted by JLH on 2008-06-09, 04:32:15 (40.0.40.10)
. .......
188: High Efficiency Speaker Asylum, They want the Mini Pearl price tag because it reminds them of Hee-Haw. (nt) (0.00)
Posted by JLH on 2008-06-09, 04:22:52 (40.0.40.10)
. .......
189: High Efficiency Speaker Asylum, RE: Huge Klipsch Corner Horn (0.00)
Posted by JLH on 2008-06-09, 04:20:18 (40.0.40.10)
150ft is way off. Considering a 20Hz wavelength is 56.2 feet in length, there would be no point in going longer. Actually, 1/4 wavelength will get you there provided the mouth is big enough. In real l .......
190: DIY HiFi Forum, Any follow-up on bench testing? (0.00)
Posted by JLH on 2008-06-06, 09:12:53 (40.0.40.10)
Brian, Just wanted to see if you ran those tests yet. Rgs, JLH .......
191: Tubes Asylum, Try to keep them around 28W plate dissipation. (0.00)
Posted by JLH on 2008-05-24, 04:28:48 (40.0.40.10)
All the ones I've seen start to show plate color past 28W. You can run them harder and they should still be fine. I just personally don't like the idea of red plates. I liked them at 380V, 74mA into a .......
192: MagneQuest/Peerless Forum, nc --) Playing with 1500VDC will probably kill me someday (0.00)
Posted by JLH on 2008-05-21, 12:49:57 (40.0.40.10)
Nah! It just tickles a little bit...at first! ;0P Rgs, JLH .......
193: High Efficiency Speaker Asylum, If you want something new and exciting look here--) (0.00)
Posted by JLH on 2008-05-15, 08:16:21 (40.0.40.10)
There is a lot more going on over at diyAudio than here. These tapped horns have been a lot of fun. Mind blowing at times. The thread is up to 75 pages now. It should give you guys plenty to read. One .......
194: Tube DIY Asylum, RE: Push Pull 845 output stage questions (0.00)
Posted by JLH on 2008-05-11, 12:11:03 (40.0.40.10)
Yes, you are probably entering A2 at the lower plate voltage. If I were you, I would go ahead with the higher voltage. I have been hit with 450V and 800V from tube amps. Let me tell you, there isn't m .......
195: Tubes Asylum, Old news (0.00)
Posted by JLH on 2008-05-07, 04:39:44 (40.0.40.10)
Those are current manufacture 6SN7 tubes in a globe package. They have been talked about before. Do a search for "globe 6SN7". .......
196: Tube DIY Asylum, I've had Edcor wind some OPTs with CFB (0.00)
Posted by JLH on 2008-04-12, 11:00:13 (40.0.40.10)
They made them exactly to my specifications. They work great and have very good bandwidth. I would use them again. .......
197: Tube DIY Asylum, Devil’s advocate and a few interesting thoughts to ponder. (0.00)
Posted by JLH on 2008-04-09, 12:25:01 (40.0.40.10)
The below are some questions I asked myself while playing around with the low hy/cap/DCR power supplies. Some of them in my mind are still unanswered. However, I know this, I’ve been very pleased with .......
198: High Efficiency Speaker Asylum, Ditto (nt) (0.00)
Posted by JLH on 2008-04-06, 19:28:15 (70.236.8.145)
. .......
199: High Efficiency Speaker Asylum, That is not a completely true statement (0.00)
Posted by JLH on 2008-04-06, 15:05:11 (70.236.8.145)
You can make a tractrix have more coloration and honk than an exponential horn. The main contributor of coloration in the tractrix is using too long a neck. If you build a 150Hz tractrix and use it wi .......
200: K&K Audio / Lundahl Transformers, RE: Audio aso transformer (0.00)
Posted by JLH on 2008-04-05, 16:55:58 (70.227.30.192)
The only thing I could think of is to break up a ground loop. Other than that, I don't think you would be doing the signal any favors. Less is more in my book. Then again, a transformer is better than .......
201: Tube DIY Asylum, I had some 3C24 tubes that looked like that. (0.00)
Posted by JLH on 2008-03-31, 03:18:55 (40.0.40.10)
The blue glow around the grid can be neat looking. .......
202: High Efficiency Speaker Asylum, Time for you to read up (0.00)
Posted by JLH on 2008-03-18, 16:29:14 (70.229.27.54)
Go here --> http://www.diyaudio.com/forums/showthread.php?s=&threadid=97674&highlight= And read up on the tapped subwoofer horn. There are several plans that have already been built and tested. Lots o .......
203: Tube DIY Asylum, No separation (0.00)
Posted by JLH on 2008-03-12, 20:37:54 (69.208.158.59)
If the plate chokes are the load for the tubes, then you will not have any separation. This is because you are sharing the last electrical supply node right before your load (chokes). Remember, the ch .......
204: DIY HiFi Forum, You're killing me Brian! (0.00)
Posted by JLH on 2008-03-07, 16:42:59 (70.236.6.126)
I just bought some of your 600 ohm LCR modules. Now you come out with these bad boys. So many parts, so little time and money! Rgs, JLH .......
205: DIY HiFi Forum, What is the inductance of this unit? (0.00)
Posted by JLH on 2008-03-07, 09:06:00 (40.0.40.10)
Brian, What is the inductance of this unit? How much signal input voltage can it handle? Can we just buy the autoformers by their self? What's the price? Thanks. Rgs, JLH .......
206: Tube DIY Asylum, That is a very creative idea. (0.00)
Posted by JLH on 2008-03-07, 05:00:06 (40.0.40.10)
This would a very inexpensive means to explore 6C33 SE land. Great idea. .......
207: SET Asylum, Tell that to the 35 year old tubes in my Radiotron radio. (0.00)
Posted by JLH on 2008-03-06, 18:08:16 (69.208.149.83)
It has type 24, 27, 35, and 47 tubes that have well over 20,000 hours on them. They all still test higher than 50% on a tube tester. .......
208: Tube DIY Asylum, What's the current draw? (0.00)
Posted by JLH on 2008-03-02, 12:28:11 (40.0.40.10)
Couple results - #1 pulling 40mA (30mA something for the 45 and some for the driver tube) results in B+ of 310V with ripple of 93mV. A stepped current change of 20% revials a dynamic impedance of 820 .......
209: Tube DIY Asylum, HL-10K-6 is the model you probably want. (nt) (0.00)
Posted by JLH on 2008-02-29, 13:30:20 (69.219.228.21)
. .......
210: SET Asylum, Best to avoid unknown Chinese amplifiers. (0.00)
Posted by JLH on 2008-02-28, 18:42:10 (69.208.149.92)
There are far too many people having problems with Chinese made equipment. Most of it is pure trash. Buy from a well established manufacturer that doesn't contract out to China. You can buy the right .......
211: Tubes Asylum, Never argue with an idiot, they will bring you down to their level then beat you with experience. (0.00)
Posted by JLH on 2008-02-26, 08:19:46 (40.0.40.10)
. .......
212: Tubes Asylum, Very true. People need to be educated buyers. (nt) (0.00)
Posted by JLH on 2008-02-26, 08:16:18 (40.0.40.10)
. .......
213: Tubes Asylum, Murphy's Law #53 - Expensive audio gear will sacrifice itself to save a $0.50 fuse. (nt) (0.00)
Posted by JLH on 2008-02-26, 06:25:53 (40.0.40.10)
. .......
214: Tubes Asylum, Don't think just because it was a SF product that manufacturing wasn't farmed out to China (nt) (0.00)
Posted by JLH on 2008-02-26, 05:59:24 (40.0.40.10)
:0P .......
215: High Efficiency Speaker Asylum, I completely disagree. (0.00)
Posted by JLH on 2008-02-17, 08:31:39 (40.0.40.10)
Digital is the primary case for corruption of imaging. Critical phasing information is lost during the digital quantization process. While the quantization process might approximate amplitude decently .......
216: SET Asylum, Then you need a different driver tube. (0.00)
Posted by JLH on 2008-02-16, 13:12:08 (40.0.40.10)
While the 26 and 6SN7 are nice sounding tubes, they lack the drive capacity to really wake up a 300B tube. Try something with a lower plate resistance and higher current. Also, don't overlook your pow .......
217: High Efficiency Speaker Asylum, Phasing information in the recording is what provides "stage" presence. (0.00)
Posted by JLH on 2008-02-16, 12:56:45 (40.0.40.10)
I agree if the crossover was reworked, then the 4430 would out image the ProAc. Phase is extremely important for good 3-D presence. .......
218: High Efficiency Speaker Asylum, RE: Ah fane (0.00)
Posted by JLH on 2008-02-11, 18:03:06 (70.236.12.185)
I am a bit biased toward the Fane, but if used in a midbass 30" or less, I like the B&C better. If you start to push past 30" to 32" in horn depth, then the B&C starts to sound recesed. On the other h .......
219: Tube DIY Asylum, Bingo!...gusser read this post. (nt) (0.00)
Posted by JLH on 2008-02-10, 18:01:19 (70.236.7.171)
. .......
220: Tube DIY Asylum, This is how I did it. (0.00)
Posted by JLH on 2008-02-10, 17:57:08 (70.236.7.171)
I screwed them together base-to-base and wired them in series. I them clipped my voltmeter to the two free end leads and set the meter for AC milivolts. I held the chokes within 6 inches of my microwa .......
221: High Efficiency Speaker Asylum, They tried doing the same thing to me. (0.00)
Posted by JLH on 2008-02-10, 17:45:17 (70.236.7.171)
I ordered 4 of the 16 ohm 8PE21 and they came in as 8 ohm models. I ended up contacting the U.S. B&C rep and they finally made good on their end. The 8PE21 is a fairly good midbass horn driver. It can .......
222: Tube DIY Asylum, RE: Then explain how? (0.00)
Posted by JLH on 2008-02-08, 18:04:31 (70.236.21.47)
Tre, You already know this answer. Full wave or bridge rectified circuits look like a series of letter "M" strung together on a scope. The choke's and capacitor's job is to fill in the valleys. Sin .......
223: Tube DIY Asylum, RE: The gist or is that grist (0.00)
Posted by JLH on 2008-02-08, 17:58:02 (70.236.21.47)
A choke's behavior is to oppose change in current flow. A cap's behavior is to gobble up and store as much current as it can. When the amplifier demands an increase in current the caps initially relea .......
224: High Efficiency Speaker Asylum, RE: Not good (0.00)
Posted by JLH on 2008-02-08, 08:34:26 (40.0.40.10)
You need tight pattren control to get "the performer in your room" imaging. The Zu speaker can't do this due to its design. Re-read what toxicport.e wrote above. Also re-read what Godzilla wrote. Whil .......
225: High Efficiency Speaker Asylum, RE: Not good (0.00)
Posted by JLH on 2008-02-08, 03:37:03 (40.0.40.10)
To me they just sounded like a poorly designed speaker. During the whole time I listened, they never sounded realistic to me. They kind of reminded me of a bad set of head phones. I have no idea what .......
226: High Efficiency Speaker Asylum, Not good (0.00)
Posted by JLH on 2008-02-07, 13:03:02 (40.0.40.10)
My personal experience is they (The Druid model) sound thin in the bass, veiled in the upper mid range, bright in the highs, and have a box like coloration. The room could have had some effect on thei .......
227: SET Asylum, RE: Because Front Panel Express is a better value. (0.00)
Posted by JLH on 2008-01-31, 18:00:23 (70.227.30.116)
I agree with price not being a sign of quality. I work in pharmaceutical ingredient process manufacturing. I know what real quality control systems are too. That is why I build most of my own tube gea .......
228: SET Asylum, Because Front Panel Express is a better value. (0.00)
Posted by JLH on 2008-01-31, 13:09:59 (70.227.30.116)
Why buy a piece of junk amplifier just for the chassis? It is already restricting you to what you can do with it because it is drilled and punched out for their design, not yours. Why not just buy the .......
229: SET Asylum, Built in USA, but designed by Japan...Aka Honda (0.00)
Posted by JLH on 2008-01-31, 13:03:16 (70.227.30.116)
I don't like to repair things that I have already paid for. This is not a debate about cars, but I apply the same thought process to my tube equipment. I want the most reliable, highest resale value, .......
230: High Efficiency Speaker Asylum, Don't go there either. (0.00)
Posted by JLH on 2008-01-31, 12:48:24 (70.227.30.116)
Why would you go to all the trouble to build a horn and have the mouth exit up high? If you are going to all the trouble you better make full use of the floor as boundary reinforcement. That horn woul .......
231: High Efficiency Speaker Asylum, Don't go there, trust us. (nt) (0.00)
Posted by JLH on 2008-01-31, 12:42:09 (70.227.30.116)
. .......
232: SET Asylum, I would never buy a piece of cr@p that I knew I would have to fix. (nt) (0.00)
Posted by JLH on 2008-01-30, 13:19:56 (40.0.40.10)
. .......
233: Tube DIY Asylum, Neither, the glass is twice as large as it needs to be ;0) (nt) (0.00)
Posted by JLH on 2008-01-09, 13:18:22 (70.225.137.172)
. .......
234: Tube DIY Asylum, It has already been done (0.00)
Posted by JLH on 2008-01-07, 17:50:06 (70.227.30.44)
John Atwood wrote an article in Issue 15 of Vacuum Tube Valley about two different RF filament powered amplifiers he built. One was a 2A3 design and the other was a 300B. The idea was to see if RF hea .......
235: Tube DIY Asylum, All mine are copper. (0.00)
Posted by JLH on 2007-12-21, 13:50:59 (69.219.235.18)
But then, I also got them over a year ago. With the price of copper still going up, my guess is they switched to Al to save on cost. Typical! .......
236: Tube DIY Asylum, Cree Schottky diodes (0.00)
Posted by JLH on 2007-12-20, 17:34:13 (69.219.227.157)
I use the 1200V rated ones most the time. For pre amps and lower voltage applications the 300V and 600V devices work well. Just remember these are solid state devices and will not handle being abused .......
237: Tube DIY Asylum, RE: Would this qualify (0.00)
Posted by JLH on 2007-12-18, 20:07:25 (69.219.237.137)
Makes sense now. I wish you well on your project. You will have to show us and tell us how it turns out. Rgs, JLH .......
238: Tube DIY Asylum, RE: Would this qualify (0.00)
Posted by JLH on 2007-12-18, 15:13:55 (40.0.40.10)
I can't quite make out what the value of C3 is in your circuit. But besides that point, the main driver behind me using these low value chokes is the practicality and sound quality. They are so small .......
239: Tube DIY Asylum, My answers. (0.00)
Posted by JLH on 2007-12-18, 05:07:51 (40.0.40.10)
This should be very interesting. I'm guessing you will provide an answer key once most people get a chance respond to this? I can't speak for others, but I find this to be very entertaining. It is alw .......
240: Tube DIY Asylum, I would have to agree with you on that. (nt) (0.00)
Posted by JLH on 2007-12-16, 21:25:19 (70.236.7.75)
. .......
241: Tube DIY Asylum, Look at "More Answers" below (0.00)
Posted by JLH on 2007-12-16, 18:33:36 (70.236.7.75)
http://www.audioasylum.com/forums/tubediy/messages/13/133283.html The best way I can describe the results in audiophool speak is it removed the syrup and wool blanket from my system. "Because you are .......
242: Tube DIY Asylum, More answers (0.00)
Posted by JLH on 2007-12-16, 18:27:57 (70.236.7.75)
EDIT: If the images don't show up, just paste the address into your browser window. Sorry html doesn't seem to be working The above is what I use in my single ended CFB pentode amplifier. Take noti .......
243: Tube DIY Asylum, To add to what NC has said. (0.00)
Posted by JLH on 2007-12-15, 14:08:55 (70.236.7.75)
Henry, As we have discussed elsewhere to some extent, I use the “Flywheel” power supply, not the “LOW Everything” power supply. The specific use is in a single ended pentode amplifier with CFB. I use .......
244: MagneQuest/Peerless Forum, RE: dumb question(s) (0.00)
Posted by JLH on 2007-12-12, 12:10:25 (69.208.158.58)
One of the main pluses of using input transformers is it isolates gound loops. Another is the inductive load of the input transformer has always sounded more dynamic than a resistive load to my ears. .......
245: MagneQuest/Peerless Forum, Good pot is hard to find. ;0) (0.00)
Posted by JLH on 2007-12-10, 04:34:41 (40.0.40.10)
RF15 spec sheet http://www.pennyandgiles.com/docGallery/83.PDF RF11 spec sheet http://www.pennyandgiles.com/docGallery/168.PDF Those audio faders sure look like works of art. Kind of expensive, but i .......
246: Tube DIY Asylum, No, too much inductance and too large a core. (nt) (0.00)
Posted by JLH on 2007-12-10, 04:07:54 (40.0.40.10)
. .......
247: SET Asylum, They are good. (0.00)
Posted by JLH on 2007-12-08, 07:44:12 (40.0.40.10)
I had some custom OPTs wound for one of my special projects. They meet all my specs and exceeded them in some areas. I would use them again in a heart beat. Very good quality for the dollar. ::: TOPIC .......
248: K&K Audio / Lundahl Transformers, A full run down (0.00)
Posted by JLH on 2007-12-05, 04:40:54 (40.0.40.10)
Let’s run through this and see what we come up with. I started by enlarging the plate curves of the 6SN7 and plotted a 47K load line at the 80V/1.5mA operation point. The maximum voltage swing along t .......
249: K&K Audio / Lundahl Transformers, RE: No (0.00)
Posted by JLH on 2007-12-03, 18:34:44 (69.219.224.130)
Sounds like you then need to pick a different bias point for your tube. You should be able to swing plenty voltage with your chokes. .......
250: K&K Audio / Lundahl Transformers, No (0.00)
Posted by JLH on 2007-12-03, 13:26:26 (69.219.224.130)
"So a choke load gives me the same gain as a resistor load, but I can obtain twice as much output for a given power supply." No, a choke will give you gain that is equal to the Mu of your tube. Resist .......
251: Tube DIY Asylum, RE: Hey, thats not mine !! (0.00)
Posted by JLH on 2007-12-01, 09:42:24 (70.225.129.45)
Mercury vapor rectifiers have virtually no internal resistance once they have dropped their normal forward voltage (usually 15V). This is very much just like silicone rectifier's 0.7V forward voltage .......
252: SET Asylum, I've seen that too. (nt) (0.00)
Posted by JLH on 2007-11-30, 12:35:28 (40.0.40.10)
. .......
253: SET Asylum, Get rid of that tube eater. (0.00)
Posted by JLH on 2007-11-30, 07:42:20 (40.0.40.10)
I have a pair of early Svetlana 300Bs that have about 9800 hours on them and still perform great. My amp runs them close to the classical 300B operating point. I run them at 360V, 65ma, -75V into a 4K .......
254: Tube DIY Asylum, Look at the grid choke impedance at 20Hz (0.00)
Posted by JLH on 2007-11-18, 05:49:02 (40.0.40.10)
Nickel version 2*Pi*20Hz*4800H = 603,185 ohms Iron version 2*Pi*20Hz*1000H = 125,663 ohms That would seem like an easy load for most pentodes to drive, don't you think? Even the iron version provide .......
255: High Efficiency Speaker Asylum, I'm so glad we had this conversation, Ha! ;0) (0.00)
Posted by JLH on 2007-11-11, 03:22:09 (40.0.40.10)
nt .......
256: High Efficiency Speaker Asylum, I thought they were called dutchmans? (nt) (0.00)
Posted by JLH on 2007-11-10, 02:38:56 (40.0.40.10)
. .......
257: Tube DIY Asylum, Current tube design trend is just like Michael Jackson. (0.00)
Posted by JLH on 2007-11-09, 14:27:13 (70.225.132.56)
They are both perfect examples of what happens when you keep on fixing something until it’s broke! All the CCS, active regulation, and specification hunting has destroyed the true beauty and simplicit .......
258: High Efficiency Speaker Asylum, Why would you order woofers without first having a plan for them? (0.00)
Posted by JLH on 2007-09-07, 05:07:14 (40.0.40.10)
I don’t know if it’s just me, but this thinking appears backwards to me. Why the heck would you buy anything without taking into consideration how you plan to integrate them into your system? Larry th .......
259: Tube DIY Asylum, RE: Make sure yrou master the language first ! (0.00)
Posted by JLH on 2007-08-24, 10:46:06 (40.0.40.10)
"Talk to our Japanese expert: Lynn Olson to learn more" Ha! Ha! Ha! That was a good one. Thanks for the laugh. .......
260: High Efficiency Speaker Asylum, Zzzzzzz..... (0.00)
Posted by JLH on 2007-06-16, 16:06:30 (69.208.148.112)
Fs is too high. You'd have to drill some holes in the chamber to open it up. I like controlling Fs with my own chamber that I can tune. .......
261: Tube DIY Asylum, Re: Because it is flawed thinking. Well maybe not so flawed... (0.00)
Posted by JLH on 2007-03-19, 18:15:10 (70.236.13.162)
Hi Steve, I can see what you are saying, however I was thinking about single ended circuits, not push-pull. I have been able to get some very nice results with single ended high Gm pentodes with CFB .......
262: Tube DIY Asylum, I totally agree. "it lost information" (0.00)
Posted by JLH on 2007-03-19, 07:03:35 (40.0.40.10)
And might I add that it was most probable that was due to the very high impedance of the screen supply. Once a person has heard a pentode with a well made and low impedance G2 supply there is no going .......
263: Tube DIY Asylum, Because it is flawed thinking. (0.00)
Posted by JLH on 2007-03-19, 06:45:33 (40.0.40.10)
Manipulation of screen voltages is a bad design choice, IMHO. The pentode was designed to be operated with a fixed screen voltage to provide more precise control over plate currents and to increase ef .......
264: Tube DIY Asylum, mikeyb follow this link and you might learn something. (0.00)
Posted by JLH on 2007-03-14, 14:14:35 (40.0.40.10)
Down near the bottom of the thread Henry has simulation pictures that show what is really happening with a low L first choke power supply. Its not too damn hard to understand. While Jeff may have not .......
265: Tube DIY Asylum, There is an error in Allied's catalog!!! (0.00)
Posted by JLH on 2007-03-11, 19:07:04 (70.236.18.54)
http://www.alliedelec.com/Images/Products/Datasheets/BM/STANCOR/Stancor_Actives-and-Passives_9280070.pdf Above link is to the Stancor data sheet to all their chokes. In the Allied catalog I got real e .......
266: Tube DIY Asylum, Consider this. (0.00)
Posted by JLH on 2007-03-11, 18:45:01 (70.236.18.54)
Consider that a speaker with 89dB sensitivity will require 128 watts to play as loudly as a 101dB sensitive speaker furnished with just 8 watts. The efficient speaker sips music from the linear surfac .......
267: DIY HiFi Forum, Thanks Brian! (0.00)
Posted by JLH on 2007-03-10, 09:58:07 (70.225.142.246)
. .......
268: DIY HiFi Forum, Can Silk 600 ohm LCR modules handle direct coupling? (0.00)
Posted by JLH on 2007-03-09, 20:56:18 (70.236.7.238)
Brian, It seems that S&B quit making their 600 ohm LCR modules. However, I was pleased to see that you sale the Silk LCR modules. My question is can the Silk modules handle direct coupling as seen i .......
269: Tube DIY Asylum, The problem with large capacitors (0.00)
Posted by JLH on 2007-03-08, 05:00:00 (40.0.40.10)
The problem with large capacitors is they compete with your output tubes for the power supply’s current. A small capacitor has much less surface area between its elements. Because of this, it also has .......
270: Tube DIY Asylum, "The rectifier doesn't matter at all" (0.00)
Posted by JLH on 2007-03-08, 04:26:28 (40.0.40.10)
I would have to disagree with the rectifier not mattering. It is fairly easy to see that the dynamic impedance of the power supply is much higher with normal tube rectifiers, and even damper diodes. M .......
271: Tube DIY Asylum, 600 ohm LCR all the way! (nt) (0.00)
Posted by JLH on 2007-03-02, 17:04:10 (70.225.128.28)
. .......
272: High Efficiency Speaker Asylum, Tom, I would have to say you hit the nail on the head. (0.00)
Posted by JLH on 2007-02-14, 06:01:23 (40.0.40.10)
While, I myself am not easily offended, I saw how Earl's choice of words ticked off a lot of people; very condescending at times. I remember reading some of his posts and telling myself "What he wrote .......
273: High Efficiency Speaker Asylum, The reality of the situation (0.00)
Posted by JLH on 2007-02-05, 07:54:46 (40.0.40.10)
Last time I tried to listen to a chart it didn't have much sound to it. ;0P There are several speakers on the market that don't measure very well, however, this one is particularly bad, and I do mean .......
274: MagneQuest/Peerless Forum, Thanks! (nt) (0.00)
Posted by JLH on 2007-01-17, 11:43:22 (40.0.40.10)
. .......
275: MagneQuest/Peerless Forum, B7-15K specs (0.00)
Posted by JLH on 2007-01-17, 08:26:27 (40.0.40.10)
Mike, I've seen two different specs stated on the Net for the B7-15K. Instead of guessing I'd like to get the info straight from the horse's mouth so to speak. What is the turns ratio? What is the p .......
276: MagneQuest/Peerless Forum, Thanks (nt) (0.00)
Posted by JLH on 2007-01-07, 13:52:32 (40.0.40.10)
. .......
277: MagneQuest/Peerless Forum, Re: Parafeed PP (0.00)
Posted by JLH on 2007-01-07, 11:15:28 (40.0.40.10)
Mike, I can't answer you question, but I can at least post up a schematic to help people visualize what you are talking about. .......
278: MagneQuest/Peerless Forum, DCR slot? (0.00)
Posted by JLH on 2007-01-07, 08:24:07 (40.0.40.10)
Dan, The spreadsheet I downloaded from your first post doesn't have a place to enter the choke's DCR. All I see is entry spots for C, L, Rp, L1, and R1. Need a little help here. Thanks. Rgs, JLH ::: .......
279: MagneQuest/Peerless Forum, Question on input values. (0.00)
Posted by JLH on 2007-01-06, 21:11:54 (40.0.40.10)
What value would you enter for the plate choke L value if you were using a plate load resistor instead of a choke? .......
280: Tube DIY Asylum, My experience and take on it. (0.00)
Posted by JLH on 2007-01-06, 21:06:51 (40.0.40.10)
TK, While I don’t make a habit of pushing tubes to their limits, most of the tubes designed for vertical defection in TVs are pretty tough tubes. I have run 6AH4GTs at 250V and 35mA for over 4 year .......
281: Tube DIY Asylum, 6c45-Pi = Sonic Trash. (nt) (0.00)
Posted by JLH on 2006-12-29, 04:13:36 (40.0.40.10)
. .......
282: MagneQuest/Peerless Forum, Thanks! (nt) (0.00)
Posted by JLH on 2006-12-16, 11:09:01 (4.224.156.122)
. .......
283: MagneQuest/Peerless Forum, resistive loaded parafeed cap size. (0.00)
Posted by JLH on 2006-12-15, 14:51:51 (4.224.162.36)
Hey Guys, Does anyone know the math used to calculate the size of the parafeed cap for a resistive loaded parafeed circuit? This is for a small signal gain stage, so I don't need or want a plate choke .......
284: K&K Audio / Lundahl Transformers, Availability of LCR phono inductors (0.00)
Posted by JLH on 2006-12-10, 18:56:48 (4.224.144.104)
Kevin, A while back Lundahl was making the 1.8H and 45mH inductors for the Tango style LCR phono correction network. What happened with them and can they still be purchased? TIA. Rgs, JLH ::: TOPIC .......
285: High Efficiency Speaker Asylum, Just let him live in ignorance(nt) (0.00)
Posted by JLH on 2006-08-19, 10:46:12 (40.0.40.10)
. .......
286: Vinyl Asylum, Audioslave and Motley Crue (nt) (0.00)
Posted by JLH on 2006-07-10, 06:39:14 (40.0.40.10)
;0) .......
287: High Efficiency Speaker Asylum, Watch your impedance. (0.00)
Posted by JLH on 2006-07-10, 06:31:44 (40.0.40.10)
Be aware that anytime you "boost" with an autoformer, your transformed impedance goes down. From what I read, this design may be best suited for solid state amps? Rgs, JLH .......
288: High Efficiency Speaker Asylum, Its the horn (0.00)
Posted by JLH on 2006-07-05, 07:22:05 (40.0.40.10)
You are experiencing a resonance in the range that is significant to the instruments you mentioned. Room placement or treatments will not solve this (As you have found out). The 811 and 511 horns both .......
289: MagneQuest/Peerless Forum, Mike take a look at PSUD. (0.00)
Posted by JLH on 2006-06-27, 08:25:37 (4.224.198.193)
Mike, ***You wrote: What is the raw dc supply volts off of the rectifier? my calcs assumed about a 600 volt supply (like you might use in a power amp) and that the choke was the first element in the p .......
290: Tube DIY Asylum, A better question would be if you have listened to any moment to moment music lately? (nt) (0.00)
Posted by JLH on 2006-06-26, 11:31:18 (40.0.40.10)
;0) .......
291: Tube DIY Asylum, Missing data, but... (0.00)
Posted by JLH on 2006-06-26, 11:20:06 (40.0.40.10)
Mike, I think I know exactly were you are headed with this. One of the things that concerned me was how are we suppose to know if this thing can handle a choke input implementation without broadcast .......
292: Tube DIY Asylum, Are those 300mH chokes Hammond 159ZA models? (nt) (0.00)
Posted by JLH on 2006-06-26, 07:23:39 (40.0.40.10)
;0) .......
293: Tube DIY Asylum, Jeff, power transformer clarification wanted. (0.00)
Posted by JLH on 2006-06-26, 06:53:05 (40.0.40.10)
Jeff, When you state 20 ohms in regards to a power transformer, is this from the center tap to one of the high voltage legs, or are you saying 20 ohms across the whole high voltage secondary? Thanks .......
294: High Efficiency Speaker Asylum, He may not be completely crazy... (0.00)
Posted by JLH on 2006-06-25, 04:10:51 (40.0.40.10)
Having came from the ranks of car audio pool, the industry is in poor shape IMO. It is just my own personal view, but I feel like the peak occurred in the late 80’s to early 90’s. Many of the finest a .......
295: High Efficiency Speaker Asylum, Are those split Altec 210's? (nt) (0.00)
Posted by JLH on 2006-06-21, 12:22:26 (40.0.40.10)
;0) .......
296: Vinyl Asylum, You just had to re-open the wounds! (0.00)
Posted by JLH on 2006-06-16, 13:55:20 (40.0.40.10)
The worst near miss was at a Goodwill store about 8 months ago. I was thumbing through the crappy record stack, AND LONG AND BEHOLD WHAT DID I SEE!!! I thought NO WAY! It was Lincoln Mayorga & Disting .......
297: High Efficiency Speaker Asylum, The F200A still lacks top end shimmer.... (0.00)
Posted by JLH on 2006-06-16, 13:31:11 (40.0.40.10)
And benefits from a good super tweeter still. Several of Fostex's woofers measure to 20KHz, but something is still lacking IMO. The interesting thing is I know I can't hear past 16KHz, but I can still .......
298: Tube DIY Asylum, Use the One Electron transformers. (nt) (0.00)
Posted by JLH on 2006-06-16, 02:57:22 (40.0.40.10)
;0) .......
299: Tube DIY Asylum, Yes (0.00)
Posted by JLH on 2006-06-15, 17:36:35 (63.18.135.36)
I’m glade I was able to put my thoughts in a translatable form. Sometimes the limitation of this typed form of communication causes us to misunderstand each other. You are right on the money with the .......
300: High Efficiency Speaker Asylum, Its Doppler distortion. (0.00)
Posted by JLH on 2006-06-15, 16:52:12 (63.18.135.36)
You are likely hearing congestion caused by Doppler distortion, not intermodular distortion. Doppler distortion is a change in pitch due to the large cone area moving back and forth as the inner porti .......
301: Tube DIY Asylum, A few points that may still need to be looked at. (0.00)
Posted by JLH on 2006-06-15, 14:08:39 (40.0.40.10)
HI Guys, http://www.nutshellhifi.com/library/ETF.html At the above URL, Lynn Olson discusses current loops in various amplifier types. In most cases, the power supply IS in the signal path. There ar .......
302: High Efficiency Speaker Asylum, "It takes a horn to catch a horn." (0.00)
Posted by JLH on 2006-06-12, 05:15:40 (40.0.40.10)
I have read this phrase before and have heard it said before as well. I'm sure it can be done without a horn subwoofer, but I don't know what it would be. I really like horn bass for its low distortio .......
303: Tubes Asylum, Try here (0.00)
Posted by JLH on 2006-06-11, 08:11:01 (40.0.40.10)
Newark Electronics carries the dual rated 440VAC/1000VDC GE poly caps. Google for Newark Electronics and search for part numbers 46F3412 and 46F3413. One is 15uF 1000VDC and the other is 17.5uF 1000VD .......
304: MagneQuest/Peerless Forum, Re: Without amp? (0.00)
Posted by JLH on 2006-06-11, 03:03:12 (40.0.40.10)
I have ran horns directly off of the head phone jack of CD players before. You lose some punch and dampening due to the higher output impedance of the CD player, but it can still get loud enough to ru .......
305: High Efficiency Speaker Asylum, Each type has its place. (nt) (0.00)
Posted by JLH on 2006-06-11, 02:21:12 (40.0.40.10)
;0) .......
306: SET Asylum, Why? (0.00)
Posted by JLH on 2006-06-02, 12:03:22 (40.0.40.10)
Just my personal opinion, but I think you should re-think what you are doing. When you wrote “I'm thinking cheap Chinese tubes and cheap iron here”, that’s where you lost me. Why would you want to bui .......
307: High Efficiency Speaker Asylum, Paul Klipsch always liked the Brook 12A... (0.00)
Posted by JLH on 2006-06-02, 09:31:23 (40.0.40.10)
I have read in several places that Paul Klipsch really liked the sound of the Brook 12A amps on his Khorns. However, finding a pair in good shape will be very difficult. If you can DIY or know someone .......
308: MagneQuest/Peerless Forum, When you really think about it... (0.00)
Posted by JLH on 2006-06-02, 09:17:33 (40.0.40.10)
Most of us guys with +105dB horns and 1 watt amps are doing that exactly. Our horns can be driven directly from the output of a phono stage, or a CD player. The only real purpose our amps serve is imp .......
309: Tube DIY Asylum, Electra-Print Audio. (nt) (0.00)
Posted by JLH on 2006-05-29, 04:36:29 (40.0.40.10)
;0) .......
310: Tube DIY Asylum, I don't agree with that. (0.00)
Posted by JLH on 2006-05-27, 05:22:50 (40.0.40.10)
I disagree that the current delivered by the power supply will always exactly equal the current drawn by the load. If you have enough inductance and the choke is doing its job, then the current drawn .......
311: MagneQuest/Peerless Forum, How much step current did you use in your simulations? (nt) (0.00)
Posted by JLH on 2006-05-24, 04:45:22 (40.0.40.10)
;0) .......
312: High Efficiency Speaker Asylum, Hey Tom, what's the status of the tapped horn patent? (nt) (0.00)
Posted by JLH on 2006-05-15, 07:54:28 (40.0.40.10)
Thanks! .......
313: High Efficiency Speaker Asylum, What are you guys using... (0.00)
Posted by JLH on 2006-05-13, 09:47:17 (40.0.40.10)
What are you guys using to cut the slot in these tubes? What is your technique? Thanks. Rgs, JLH .......
314: K&K Audio / Lundahl Transformers, 6C45Pi = Sonic trash (nt) (0.00)
Posted by JLH on 2006-05-13, 04:54:51 (40.0.40.10)
. .......
315: Tube DIY Asylum, Two Lane Blacktop - A true classic movie. (nt) (0.00)
Posted by JLH on 2006-04-27, 12:53:54 (40.0.40.10)
;0) .......
316: High Efficiency Speaker Asylum, Totally unnecessary (0.00)
Posted by JLH on 2006-04-20, 07:33:19 (40.0.40.10)
Your design is way over the top for its intended application. It would be far easier to build two Labhorns and place one in each corner for stereo bass. The Labhorn has enough excursion reserves that .......
317: Tube DIY Asylum, How about this? (0.00)
Posted by JLH on 2006-04-11, 04:27:40 (40.0.40.10)
Why not build two front end circuits, one HF and one LF, then combine the signals with a high quality bridging transformer? Rgs, JLH .......
318: MagneQuest/Peerless Forum, Hey Mikey! This CFB thing isn't going away. (0.00)
Posted by JLH on 2006-03-27, 06:15:36 (40.0.40.10)
Kyle, Please forgive me for somewhat hijacking your thread. Mikey, Any chance we could convince you into making some TO-350, A-441, A-440, or S217-D transformers? Or even cooler would be some SE critt .......
319: Tube DIY Asylum, My personal experience. (0.00)
Posted by JLH on 2006-03-23, 04:16:00 (40.0.40.10)
While Hammond specs them like they are rated for commercial applications, they are not. Remember, the 200 and 700 series are early Hammond designs that are inadequately designed. I tried to use the mo .......
320: Tube DIY Asylum, No (0.00)
Posted by JLH on 2006-03-20, 03:07:21 (40.0.40.10)
The Hammond 700 series plate transformers will hum and get very hot if your mains are 120V. If you want to use Hammond then I suggest you use one of their 300 series with 120V primaries. Rgs, JLH ::: .......
321: High Efficiency Speaker Asylum, PDF of the patent in discussion - here (0.00)
Posted by JLH on 2006-02-24, 09:15:40 (40.0.40.10)
http://www.pat2pdf.org/patents/pat20060034475.pdf Earl, I have not had much time to read the patent, but this appears to be a step beyond the JBL coherent phasing plug. To the best of my knowledge, .......
322: Tube DIY Asylum, Par is correct. (nt) (0.00)
Posted by JLH on 2006-02-23, 04:07:51 (40.0.40.10)
. .......
323: High Efficiency Speaker Asylum, Why do you think you need a 15" woofer? (0.00)
Posted by JLH on 2006-02-09, 14:33:57 (40.0.40.10)
The evm12l you already have will be much better suited for the crossover point you have in mind. Rgs, JLH .......
324: SET Asylum, “If you think that a capacitor is not an improvement over a transformer, then you’re welcome to your opinion” (0.00)
Posted by JLH on 2006-02-04, 10:21:52 (40.0.40.10)
“If you think that a capacitor is not an improvement over a transformer, then you’re welcome to your opinion” I read the PDF file on Zen ver. 8 and found this statement completely laughable. Just in c .......
325: High Efficiency Speaker Asylum, The Cogent drivers are NOT phenolic. They are carbon fiber. (NT) (0.00)
Posted by JLH on 2006-01-17, 04:02:38 (40.0.40.10)
. .......
326: High Efficiency Speaker Asylum, Maybe this will be helpful. (0.00)
Posted by JLH on 2006-01-13, 08:33:21 (40.0.40.10)
Earl, In all due respect I was some what put off by the way you phrased the question. Early on you made a blanket statement that the reduction of flux modulation does not hold water. (Absence of pro .......
327: MagneQuest/Peerless Forum, 50% is too high. 10% - 15% is more ideal. (0.00)
Posted by JLH on 2006-01-07, 04:30:27 (40.0.40.10)
With 50% cathode feedback, you basically have a cathode follower output stage. You will need a very serious driver stage to swing enough voltage to get any kind of output power. Cathode feedback is mu .......
328: High Efficiency Speaker Asylum, Re: What is the max depth your setup can cut? (0.00)
Posted by JLH on 2005-12-20, 13:06:17 (40.0.40.10)
The setup is not depth limited, it is weight limited. Anything over 120 lbs. and it starts to get unstable at RPMs over 200 even when the work is well balanced. Not to mention I don't like trying to m .......
329: High Efficiency Speaker Asylum, Re: Q for those who've turned horns on a lathe - how much HP is enough? (0.00)
Posted by JLH on 2005-12-20, 07:30:09 (40.0.40.10)
Sorry, but no. I have made three pairs, and had my fill of them. I have come to the conclusion that they are too much work to be making for others. Moving around 200 lbs. of wood gets old real quick. .......
330: Tubes Asylum, With tubes you are... (0.00)
Posted by JLH on 2005-12-20, 03:01:56 (40.0.40.10)
passing the signal through wire and a vacuum. With solid state, well...your are filtering your music signal through rocks. LOL! Given a properly designed circuit, tubes are always a purer form of ampl .......
331: High Efficiency Speaker Asylum, Re: Q for those who've turned horns on a lathe - how much HP is enough? (0.00)
Posted by JLH on 2005-12-20, 02:48:13 (40.0.40.10)
Doug, 1/2HP is enough for small 350Hz horns. I use the older version of the Sears wood lathe to turn all my horns. I think the Max developed HP is 1HP with the norm being 1/2HP. I turn 35" round horns .......
332: High Efficiency Speaker Asylum, "why bother?", exactly. (nt) (0.00)
Posted by JLH on 2005-12-02, 03:33:46 (40.0.40.10)
. .......
333: High Efficiency Speaker Asylum, I'm here. (0.00)
Posted by JLH on 2005-11-30, 11:32:10 (40.0.40.10)
Larry, What did you have in mind? Private message me through Asylum mail or through TM. Rgs, JLH .......
334: High Efficiency Speaker Asylum, So, what exactly does ass sound like? LOL (nt) (0.00)
Posted by JLH on 2005-11-27, 03:02:08 (40.0.40.10)
;0P .......
335: High Efficiency Speaker Asylum, Maybe impossible for you. (nt) (0.00)
Posted by JLH on 2005-11-22, 04:09:01 (40.0.40.10)
. .......
336: High Efficiency Speaker Asylum, Sure. (nt) (0.00)
Posted by JLH on 2005-11-18, 09:25:56 (40.0.40.10)
. .......
337: High Efficiency Speaker Asylum, Send me a PM and I'll show you why. (nt) (0.00)
Posted by JLH on 2005-11-17, 19:14:38 (40.0.40.10)
. .......
338: High Efficiency Speaker Asylum, Not practical IMO. (nt) (0.00)
Posted by JLH on 2005-11-17, 16:48:14 (40.0.40.10)
. .......
339: High Efficiency Speaker Asylum, How much $$$ was the upgrade kit? (nt) (0.00)
Posted by JLH on 2005-11-14, 08:37:42 (40.0.40.10)
. .......
340: K&K Audio / Lundahl Transformers, Where is best location to use amorphous x-formers? (0.00)
Posted by JLH on 2005-11-13, 18:15:33 (63.18.129.62)
I was wondering if amorphous transformers provide more sonic benefits as an input transformer, an interstage transformer, or as the output transformer. In other words, if you only have enough $$$ put .......
341: High Efficiency Speaker Asylum, The S&W .500 Mag makes for one heck of a pin gun. (nt) (0.00)
Posted by JLH on 2005-10-29, 05:33:13 (40.0.40.10)
;0) .......
342: High Efficiency Speaker Asylum, Your "tweeters"... (0.00)
Posted by JLH on 2005-10-28, 16:18:37 (4.224.192.144)
I really can't tell in the picture, but they look like they may be Vitavox S2 compression drivers. Are they? Rgs, JLH .......
343: High Efficiency Speaker Asylum, Exactly. (nt) (0.00)
Posted by JLH on 2005-10-24, 12:23:11 (4.224.195.206)
. .......
344: High Efficiency Speaker Asylum, They are sonic garbage. (nt) (0.00)
Posted by JLH on 2005-10-23, 19:46:59 (4.225.104.89)
. .......
345: MagneQuest/Peerless Forum, I vote for the MQA-15 too. (nt) (0.00)
Posted by JLH on 2005-10-21, 04:04:23 (40.0.40.10)
;0) .......
346: High Efficiency Speaker Asylum, Re: Emilar EC600 in a bass horn (0.00)
Posted by JLH on 2005-10-20, 05:35:21 (40.0.40.10)
Steve, Yes, reactance annulling works for compression drivers too. Take a moment and think about it. There is really no difference between a compression driver and a woofer except for size. The compre .......
347: High Efficiency Speaker Asylum, Re: Does anyone have pics of Romy's horns? (0.00)
Posted by JLH on 2005-09-28, 12:19:25 (40.0.40.10)
Hey Jim, I will be biting my tongue here, so bare with me. I too feel like I have been a positive addition to the AA over the years. Sure, I’ve gone a few rounds with some folks on ideas I did not .......
348: High Efficiency Speaker Asylum, Re: Does anyone have pics of Romy's horns? (0.00)
Posted by JLH on 2005-09-28, 09:41:22 (40.0.40.10)
Hey Dave, I posted a link to them a few weeks back and the Moderator deleted my post. It seems that anything Romy related is deleted within a nanosecond here. Shoot me a private e-mail through AA ma .......
349: High Efficiency Speaker Asylum, What exactly do you think the Karlson is? (0.00)
Posted by JLH on 2005-09-15, 04:43:55 (40.0.40.10)
The Karlson is a ported box. The port feeds into the top part of the front chamber slot. This port is tunable to what ever is possible with the woofer and box volume combination. The rear chamber on a .......
350: High Efficiency Speaker Asylum, Re: Basic question about a crossovers.....why use one? (0.00)
Posted by JLH on 2005-09-05, 04:10:58 (40.0.40.10)
Yes, this is one of the reasons why some like the higher order crossovers. Personally, I prefer a first order crossover with horns. However, there have been times when I have used a combination of cro .......
351: High Efficiency Speaker Asylum, Re: Basic question about a crossovers.....why use one? (0.00)
Posted by JLH on 2005-09-04, 12:34:37 (40.0.40.10)
If you don’t high pass the midrange it will result in high Doppler distortion and phasing problems. Think of it this way, if you don’t high pass it the diaphragm of the midrange will be pumping back a .......
352: MagneQuest/Peerless Forum, Re: Question: Cathode feedback with parafeed OPT? (0.00)
Posted by JLH on 2005-09-01, 08:19:19 (4.224.81.246)
I see what you are saying now. You are suggesting using the secondary as both CFB and the speaker output connection. I suppose it could work. Try it and let us know how it goes. Rgs, JLH .......
353: MagneQuest/Peerless Forum, Re: Question: Cathode feedback with parafeed OPT? (0.00)
Posted by JLH on 2005-08-31, 10:59:00 (40.0.40.10)
No, the DC current flowing in the secondary from the cathode current would most likely saturate the core. If you wanted a parafeed setup with CFB, then you would need the plate choke equipped with the .......
354: MagneQuest/Peerless Forum, Re: Since the Sovtek 2A3 has not such a good reputation as (0.00)
Posted by JLH on 2005-07-15, 03:42:33 (40.0.40.10)
I've done that (300B-it-300B) before and it was bland sounding. Much better results came about with using the type 10, 10Y, or 801A. You must deal with the higher voltage filament of the 10, but the s .......
355: High Efficiency Speaker Asylum, Re: help pick a Karlson plan for Ulfman's forum. (0.00)
Posted by JLH on 2005-06-08, 19:59:08 (4.224.99.48)
Hey Freddy, I say go for the X15 loaded with an Eminence Delta Pro 15. Rgs, JLH .......
356: High Efficiency Speaker Asylum, Flare types are very application dependent. (0.00)
Posted by JLH on 2005-03-22, 05:00:45 (40.0.40.10)
All flare types have their place. The hyperbolic is great for bass horns in which you want the extension to meet or exceed the Fc of the horn. The exponential is very useful for mid bass horns wher .......
357: High Efficiency Speaker Asylum, Tom Danley is back in business! (0.00)
Posted by JLH on 2005-03-12, 10:05:33 (4.224.198.157)
See link. .......
358: Tubes Asylum, Re: high current for filament Re: Russian military 6C19PI or 6c19n-b output tubes, unobtanium ? (0.00)
Posted by JLH on 2005-03-10, 03:50:55 (40.0.40.10)
These tubes require large amounts of heater current because it takes large cathodes to pass a lot of plate current. Big cathodes require big heaters to maintain high enough temperatures for thermal io .......
359: SET Asylum, Maybe you should then look into C-core OPTs? (0.00)
Posted by JLH on 2005-03-02, 19:06:30 (4.224.249.195)
Or even R-core OPTs. I'm sure you could turn something up at a lower price. However, I don't think the performance will be as good as the Plitrons. If you have never heard them, you are missing out. B .......
360: SET Asylum, Why don't you just... (0.00)
Posted by JLH on 2005-03-01, 18:32:09 (4.224.198.253)
buy a purpose made toroidal SE OPT from Plitron? See link. .......
361: High Efficiency Speaker Asylum, Looks like it to me. (0.00)
Posted by JLH on 2005-02-24, 10:58:22 (40.0.40.10)
The low frequency resonance appears to be centered at approximately 380Hz too. (See the third graph down) Although, I personally would not use it down that low. Rgs, JLH .......
362: High Efficiency Speaker Asylum, Wise words Paul. (0.00)
Posted by JLH on 2005-02-24, 04:50:48 (40.0.40.10)
Prototypes are the only practical way to experiment before building the final example. You sure can burn up a lot of wood, $$$, and time on a crapshoot. All builders should take their time and explore .......
363: High Efficiency Speaker Asylum, Re: LeCleach (0.00)
Posted by JLH on 2005-02-23, 04:58:38 (40.0.40.10)
I don’t recall the .707 rule of thumb, but that too works out pretty well for predicting how low your mid range horn will go. Although, it has not worked out for some compression drivers. More expe .......
364: High Efficiency Speaker Asylum, Both JBL 2440, and 2441. Varies from customer to customer. (nt) (0.00)
Posted by JLH on 2005-02-21, 03:41:09 (40.0.40.10)
. .......
365: High Efficiency Speaker Asylum, Why is it... (0.00)
Posted by JLH on 2005-02-08, 03:50:22 (40.0.40.10)
that I feel like us regular AA guys all pretty much know what’s going one with a horn, but we still insist on preaching to the choir? Ha! Have a good day. Rgs, JLH .......
366: High Efficiency Speaker Asylum, The gray area. (0.00)
Posted by JLH on 2005-02-07, 04:36:05 (40.0.40.10)
Hi Paul, Like you said length and mouth area are both important parts of the equation. However, I differ slightly in that I feel that length and flare rate has a more dominate roll than mouth size. .......
367: Tube DIY Asylum, Re: I too prefer the tetrode / pentode sound now. (0.00)
Posted by JLH on 2005-02-02, 11:02:28 (40.0.40.10)
mikeyb, I've looked at the Lundahl and while it does break out a set of windings for CFB, they are 25%, which is really too high. I have found that the point of diminishing returns begins between 8 .......
368: Tube DIY Asylum, I just use gas regulator tubes. (0.00)
Posted by JLH on 2005-02-02, 04:14:07 (40.0.40.10)
For the 165V screen supplies I just use a dropping resistor off of the main B+ and then stack a 0A3 and 0B3 followed by a 0.1uF bypass cap. Works great and sounds good too. Rgs, JLH .......
369: Tube DIY Asylum, Re: OPT details please (0.00)
Posted by JLH on 2005-02-02, 04:08:41 (40.0.40.10)
Hi Jim, These OPTs are custom one-offs that one of my old college buddies made for me. They are regular bobbin wound e-i cores. Nothing special except the screen and CFB windings. He did have to go .......
370: Tube DIY Asylum, I too prefer the tetrode / pentode sound now. (0.00)
Posted by JLH on 2005-02-01, 03:50:16 (40.0.40.10)
More specifically, single ended ultra-linear with separate screen winding, and cathode feedback. The ultra-linear tap is 40% and the CFB is 10%. Very low output impedance with the CFB in place; as low .......
371: Tubes Asylum, Re: 6LW6 (0.00)
Posted by JLH on 2005-01-25, 03:42:23 (40.0.40.10)
Mike, I would advise against using most sweep tubes in triode mode. The reason being most have Vg2 max ratings between 175V and 220V. If you triode strap them, the tube will have runaway current pro .......
372: Tubes Asylum, You'll get better results with a acetone bath and... (0.00)
Posted by JLH on 2005-01-17, 18:06:59 (4.225.106.84)
dry ice. The acetone bath with dry ice also gives you better control over how fast the temperature is dropped. Just wrap up the tube and sink it to the bottom of a can of acetone. Next start adding dr .......
373: Tubes Asylum, Source for 13E1 in U.S.? (0.00)
Posted by JLH on 2005-01-17, 10:20:27 (40.0.40.10)
Anybody here know of any reliable source for a few pair of 13E1 tubes in the U.S.? I've seen a few places over seas, but price and shipping charges seem pretty high. Any suggests. TIA! Rgs, JLH ::: TO .......
374: Vinyl Asylum, Please let us know how you like. (nt) (0.00)
Posted by JLH on 2005-01-11, 03:55:10 (40.0.40.10)
. .......
375: Tube DIY Asylum, I second this suggestion. Jack is a great guy. (nt) (0.00)
Posted by JLH on 2005-01-10, 03:25:20 (40.0.40.10)
. .......
376: High Efficiency Speaker Asylum, My vote is planned obsolescence. (0.00)
Posted by JLH on 2005-01-07, 04:27:11 (40.0.40.10)
One of the things that really puzzled me was why the Lab12, and HL10 woofers were made with foam surrounds instead of rubber. The abuse these woofers take in the Labhorn and alike, I would think rubbe .......
377: OTL Asylum, A 6AS7 ain't no 6C33. (nt) ;0) (0.00)
Posted by JLH on 2005-01-06, 04:23:35 (40.0.40.10)
. .......
378: High Efficiency Speaker Asylum, Clarification: Same MR drivers, but different horns. (nt) (0.00)
Posted by JLH on 2004-12-29, 04:00:37 (40.0.40.10)
. .......
379: OTL Asylum, Re: Joule / 6C33C-B questions (0.00)
Posted by JLH on 2004-12-29, 03:52:43 (40.0.40.10)
The biggest, or only problem I have seen is due to the high heater current consumption of the 6C33. What happens over a period of ~6 months or so, is the socket contacts start to discolor and create a .......
380: High Efficiency Speaker Asylum, Re: Belle vs. La Scala (0.00)
Posted by JLH on 2004-12-28, 03:47:11 (40.0.40.10)
You really can't put the Cornwall in the same class as a fully horn loaded speaker. The Cornwall uses different tweeters and midrange horns (i.e. cheaper) also. The Cornwall lacks the midbass energy t .......
381: High Efficiency Speaker Asylum, Re: Belle vs. La Scala (0.00)
Posted by JLH on 2004-12-27, 07:22:00 (40.0.40.10)
The main difference is the midrange horn in the Belle is shorter. IME the Belle has a much smoother and less colored midrange because of this. I've always thought if you could take the bass of the K-h .......
382: Tubes Asylum, Anybody know the patent # of Hafler & Keroes Ultra-linear "invention"? (0.00)
Posted by JLH on 2004-12-09, 05:17:38 (40.0.40.10)
I know Hafler & Keroes were not the first ones to discover ulra-linear, but I'm just interested in reading their U.S. patent on it. TIA Rgs, JLH .......
383: MagneQuest/Peerless Forum, Great info, thanks Mike. (nt) (0.00)
Posted by JLH on 2004-12-08, 16:41:33 (4.224.198.252)
. .......
384: MagneQuest/Peerless Forum, Acrosound TO-350 and Dynaco A-440 question. (0.00)
Posted by JLH on 2004-12-08, 04:18:55 (40.0.40.10)
Hey Mike, I did a search on the Dynaco A-441 and found you posted that the tertiary windings on this critter are actually 16.6% opposed to the popular belief of 43%. My question is, do the Acrosound .......
385: Tube DIY Asylum, Just be aware that... (0.00)
Posted by JLH on 2004-10-26, 12:53:33 (40.0.40.10)
The DC voltage drop across the plate choke of the 6N1P will add to the the 45's bias voltage. Therefore, the voltage across the 45's cathode resistor plus the voltage across the plate choke will equal .......
386: Tube DIY Asylum, If you choose Hammond, use the 300 series. (0.00)
Posted by JLH on 2004-10-26, 12:49:29 (40.0.40.10)
The 300 series are so much better than the 200 series its not even funny. You can also look at the toroid transformer from Toroid Corp of Maryland. It is rated for 750mA and will fit in one hand. http .......
387: MagneQuest/Peerless Forum, Fine with me; lets me know who to not buy from. (nt) (0.00)
Posted by JLH on 2004-10-25, 04:50:46 (40.0.40.10)
. .......
388: Water Cooler, Fine with me; just lets me know who to not buy from. (nt) (0.00)
Posted by JLH on 2004-10-25, 04:48:26 (40.0.40.10)
. .......
389: High Efficiency Speaker Asylum, Thanks for the clarification.(nt) (0.00)
Posted by JLH on 2004-10-19, 04:31:48 (40.0.40.10)
. .......
390: High Efficiency Speaker Asylum, Re: A little OT, but Jim what happened to Audiopax WRT Avantgrade?(nt) (0.00)
Posted by JLH on 2004-10-18, 14:01:49 (40.0.40.10)
Jim, I thought there was a relationship with Avantgrade and Audiopax. Avantgrade was promoting the Audiopax amplifiers (e.g. Audiopax Model 88) for use with their horns at one time. I was just curio .......
391: High Efficiency Speaker Asylum, A little OT, but Jim what happened to Audiopax WRT Avantgrade?(nt) (0.00)
Posted by JLH on 2004-10-18, 09:27:09 (40.0.40.10)
. .......
392: High Efficiency Speaker Asylum, Re: Edgarhorn "Signature" Slimline Drivers (0.00)
Posted by JLH on 2004-10-11, 08:54:38 (40.0.40.10)
GT, I don't know the brand of the drivers, but was able to find a picture of the Signature Slimlines. One thing to keep in mind about horns is, the brand of drivers really don't matter as much as th .......
393: Tube DIY Asylum, Need to be careful with 394A (0.00)
Posted by JLH on 2004-10-07, 05:14:57 (40.0.40.10)
The 394A's are the ST shaped tubes to the far right in the picture. The globe shaped tubes to the left of the 394A's are 722A's (aka globe 287A's) When you use the grid as the plate connection, and th .......
394: High Efficiency Speaker Asylum, Predicted SPL limit ~121dB at Xmax. (nt) (0.00)
Posted by JLH on 2004-10-04, 09:49:26 (40.0.40.10)
. .......
395: High Efficiency Speaker Asylum, This is the woofer to try. (0.00)
Posted by JLH on 2004-10-04, 04:51:30 (40.0.40.10)
Tox try this one http://www.bcspeakers.com/pdf/component/12pz32.pdf Go ahead and model this woofer in something like a 30Hz sub horn with the following values for McBean: S1 = 218.2cm^2, S2=3735.94cm^ .......
396: Tube DIY Asylum, Re: I've listened to Chris' amp... (0.00)
Posted by JLH on 2004-09-24, 04:49:04 (40.0.40.10)
The octal 6SJ7 has a fuller image presentation over that of the EF86. At least this is what I heard with my ears. The tone of the 6SJ7 is warmer and fatter. This can really be heard on the trumpets. W .......
397: Tube DIY Asylum, I've listened to Chris' amp... (0.00)
Posted by JLH on 2004-09-23, 05:18:19 (40.0.40.10)
And it has great tone. If I were you guys, I would ditch the EF86 in favor of the 6SJ7. Pretty much everything Chris writes about this amp is spot on with my observations. The thing that is very strik .......
398: High Efficiency Speaker Asylum, Ping RCA-fan. (0.00)
Posted by JLH on 2004-09-21, 07:59:03 (40.0.40.10)
Looking for info on Fostex pro tweeters. Rgs, JLH .......
399: High Efficiency Speaker Asylum, Anyone have info on Fostex T945 tweeters? (0.00)
Posted by JLH on 2004-09-20, 14:32:32 (40.0.40.10)
I ran across some that are blown. Didn't know if new diaphragms were available for them. Any technical specs would be nice to see as well. TIA. Rgs, JLH .......
400: SET Asylum, Re: 2a3 vs 45 vs 300b (0.00)
Posted by JLH on 2004-09-16, 04:46:24 (40.0.40.10)
Frank, Not that this will do you much good with your current amp, but for Rock and Speed Metal, it is hard to beat a good SE UL EL34 at max plate voltage and dissipation. Rgs, JLH .......
401: Tube DIY Asylum, Been hitchhiking lately? LOL! (0.00)
Posted by JLH on 2004-09-16, 04:42:17 (40.0.40.10)
:0) .......
402: DIY HiFi Forum, You have to be joking. (0.00)
Posted by JLH on 2004-09-10, 05:21:42 (40.0.40.10)
Before reading the below text please understand that it is impossible to portray one’s tone in words most the time. The tone of this post should be read as if you were talking to some one that is amaz .......
403: High Efficiency Speaker Asylum, The English URL (0.00)
Posted by JLH on 2004-09-03, 10:06:55 (40.0.40.10)
http://www.cornu.de/en/index.html Rgs, JLH .......
404: Vinyl Asylum, Not according to Marshall and Sanow. (0.00)
Posted by JLH on 2004-08-06, 12:37:33 (40.0.40.10)
Actually, load selection if far more important than caliber choice alone. There are cases where certain .45 caliber loads have less incapacitating ability than a .357 magnum. The same holds true for t .......
405: High Efficiency Speaker Asylum, what low-price FFT? (nt) - Good luck, ~$3K with mic (nt) (0.00)
Posted by JLH on 2004-08-02, 20:08:44 (4.224.54.38)
. .......
406: High Efficiency Speaker Asylum, Nope, RTA is way too slow. (nt) (0.00)
Posted by JLH on 2004-08-02, 11:10:58 (40.0.40.10)
. .......
407: High Efficiency Speaker Asylum, Well said. (0.00)
Posted by JLH on 2004-08-02, 05:09:07 (40.0.40.10)
weltersys, This is exactly the same observation I have had with the folded horns I've built. There are plenty of detrackers on this Board that will argue that high frequencies do not behave like li .......
408: High Efficiency Speaker Asylum, Re: 291 vs. 2440 (0.00)
Posted by JLH on 2004-07-27, 21:08:14 (4.225.111.226)
N-Set, When used within the proper bandwidths (i.e. at or above 500Hz) both the JBL and Altec drivers can sound fairly good. But, the Altec with its more appropriately sized diaphragm out performs t .......
409: DIY HiFi Forum, Will the real mesh 50 please stand up. (0.00)
Posted by JLH on 2004-07-14, 05:27:44 (40.0.40.10)
Isn’t She beautiful? .......
410: DIY HiFi Forum, Type 50 wish list. (0.00)
Posted by JLH on 2004-07-14, 05:21:08 (40.0.40.10)
Hey Brian, I know you have heard it before, but here is the wish list of how I would like to see the type 50 triode made. 1.) No top mica. 2.) Make the plate structure like the PX25 and 205D. Do NOT .......
411: SET Asylum, Those are fakes. Like GEO says, the gold pins are a dead give away. (nt) (0.00)
Posted by JLH on 2004-07-09, 04:52:13 (40.0.40.10)
. .......
412: MagneQuest/Peerless Forum, The 6C45Pi is to blame, not your choke. (0.00)
Posted by JLH on 2004-06-30, 05:24:27 (40.0.40.10)
Here is a cut and paste of a message I sent to some one else. See below: "You guys got me going now. I have to add that the data on Pete’s page supports some of what I have heard with various tubes. O .......
413: MagneQuest/Peerless Forum, Re: 6C45 OP's (0.00)
Posted by JLH on 2004-06-29, 04:49:04 (40.0.40.10)
Take the 6C45Pi down to 10mA to 15mA of plate current and them tell us what you hear. Do this just by increasing the cathode resistor value. Trust me, it will sound different. Rgs, JLH .......
414: Vinyl Asylum, What was the best belt driven Dual TT that was made? (nt) (0.00)
Posted by JLH on 2004-06-11, 13:01:46 (40.0.40.10)
. .......
415: High Efficiency Speaker Asylum, True. (nt) (0.00)
Posted by JLH on 2004-06-10, 10:17:50 (40.0.40.10)
. .......
416: High Efficiency Speaker Asylum, I'm sure your company could make a customer driver... (0.00)
Posted by JLH on 2004-06-10, 10:13:00 (40.0.40.10)
that would just about equal the ALE driver, at 1/100th of the cost. I can see it already; the dollars signs pop up in the Custom Dept manager's eyes just like you see in cartoons. I know Eminence woul .......
417: High Efficiency Speaker Asylum, The cure is worse than the illness. (0.00)
Posted by JLH on 2004-06-10, 09:57:47 (40.0.40.10)
Hey Ed, My point of view is that is if one goes to the trouble of chasing the highest purity with horns, why run it through a digital Cuisinart? Digital band-aids are not the way to go in my opinion .......
418: DIY HiFi Forum, Looks like a B&C Speakers DE12. (nt) (0.00)
Posted by JLH on 2004-06-10, 04:44:51 (40.0.40.10)
. .......
419: High Efficiency Speaker Asylum, Re: Here's some horns on ebay that are for the truely commited (and unmarried) 'philes: (0.00)
Posted by JLH on 2004-06-09, 12:38:24 (40.0.40.10)
According to the description and a few quick calculations, it appears it should reach down to the 40Hz to 45Hz range. Well, provided the driver is capable, which I seriously doubt. Additionally, a pai .......
420: Tube DIY Asylum, Your friend is correct. (nt) (0.00)
Posted by JLH on 2004-06-08, 10:05:16 (40.0.40.10)
. .......
421: Tube DIY Asylum, Link to schematic for Thorsten’s modified Joplin with neutralising caps? (0.00)
Posted by JLH on 2004-06-05, 20:31:57 (4.224.54.70)
The last known link I had for it is dead now. It was: http://www.diyhifisupply.com/KYWJoplin/AmpSch.jpg Is there another link to the schematic? I wanted to study it a little bit. Thanks guys. Rgs, JLH .......
422: High Efficiency Speaker Asylum, There are much bigger fish to fry than wire. (nt) (0.00)
Posted by JLH on 2004-06-04, 04:41:54 (40.0.40.10)
. .......
423: Tubes Asylum, Sounds about right for the 10Y. (0.00)
Posted by JLH on 2004-05-19, 10:09:43 (40.0.40.10)
You'll never get a 10, 801A, 10Y, etc. below 3.8K of Rp. This is one of the beauties of the 10Y, it doesn't change Gm and Rp so drastically. IMO, this is one reason why it sounds so good, not to menti .......
424: K&K Audio / Lundahl Transformers, What about the 1682,1664, and 1663? (0.00)
Posted by JLH on 2004-05-15, 20:06:53 (4.224.249.218)
Kevin, Will we be seeing these available in amorphous cores too? No offense, but my ears tell me that these trannys sound better than their big brothers when running tubes like 45, 71A, 183, etc. T .......
425: MagneQuest/Peerless Forum, What's the DCR of the BCP-16NI GC? (nt) (0.00)
Posted by JLH on 2004-05-14, 05:02:15 (40.0.40.10)
;0) .......
426: Tube DIY Asylum, Electra-Print PSA-2 (0.00)
Posted by JLH on 2004-04-25, 13:17:59 (4.225.104.160)
What you describe is the way Jack winds the PSA-2 phase spliter. You do have to have more more turn to over come the losses. I've used the PSA-2 before, and it works pretty damn good. Rgs, JLH ::: TOP .......
427: High Efficiency Speaker Asylum, If you come up with a new way, you'd be a very rich man! :0) (nt) (0.00)
Posted by JLH on 2004-04-23, 13:18:22 (40.0.40.10)
. .......
428: High Efficiency Speaker Asylum, Some comments and links to articles... (0.00)
Posted by JLH on 2004-04-23, 05:59:39 (40.0.40.10)
Dominic, You have to have a compression ratio in relation to diaphragm area vs. phase plug slit area. This is how we gain the most efficiency. The trade off being made is a reduction of usable diaph .......
429: High Efficiency Speaker Asylum, Re: Stop and see Jack at Electra-Print Audio! (0.00)
Posted by JLH on 2004-04-13, 10:00:07 (40.0.40.10)
Jack usually has several amps on hand, and a full Edgarhorn system. Well, worth a listen. Besides, he's a great guy to talk with. Rgs, JLH .......
430: High Efficiency Speaker Asylum, Stop and see Jack at Electra-Print Audio! (0.00)
Posted by JLH on 2004-04-12, 10:08:10 (40.0.40.10)
. .......
431: Tube DIY Asylum, Use a 6BY5 dual damper diode. (nt) (0.00)
Posted by JLH on 2004-04-12, 05:54:03 (40.0.40.10)
. .......
432: High Efficiency Speaker Asylum, Re: Tractrix horn. (0.00)
Posted by JLH on 2004-04-07, 04:51:24 (40.0.40.10)
Clive, IME if you are going for rectangular shape, then making the horn with two curved and two flat surfaces will not make any audible difference between having all four sides curved. You can actua .......
433: High Efficiency Speaker Asylum, Re: Of course you two would disagree. (0.00)
Posted by JLH on 2004-04-02, 08:12:08 (40.0.40.10)
Hi Mike, The sub horn I used is one I designed to my own requirements. It is a quarter-sized 35Hz hyperbolic-exponential with M=0.65 horn loaded with a JBL 2242. It is a consol shaped cabinet that h .......
434: High Efficiency Speaker Asylum, Of course you two would disagree. (0.00)
Posted by JLH on 2004-04-02, 04:22:27 (40.0.40.10)
Once again this is where measured or predicted performance diverges from sound quality. If you’re into the teenager trunk rattling fart mobiles that boom bass by your house at 2AM in the morning than .......
435: High Efficiency Speaker Asylum, Re: B-deap-32 (0.00)
Posted by JLH on 2004-04-01, 18:36:39 (4.224.138.68)
The B-deap-32 is a commercial product and plans are not available for it. Fred is right; you should probably try the Lab12 sub horn. Rgs, JLH .......
436: High Efficiency Speaker Asylum, Re: 30Hz basshorn (0.00)
Posted by JLH on 2004-04-01, 18:33:42 (4.224.138.68)
You did the horn length estimation correctly, but the mouth is way too small for the horn to even work marginally in a corner. That is why you see the dropping SPL from 120Hz down to about 45Hz and al .......
437: Tube DIY Asylum, Yep, 4mA is too low an op point for 12B4. Shoot for at least 15mA (nt) (0.00)
Posted by JLH on 2004-04-01, 05:51:22 (40.0.40.10)
. .......
438: Tube DIY Asylum, Try a 6AH4, sounds better than 6CK4 to my ears. (nt) (0.00)
Posted by JLH on 2004-03-30, 11:30:42 (40.0.40.10)
. .......
439: Tube DIY Asylum, Re: PP845 schematic (sketch)...comments? (0.00)
Posted by JLH on 2004-03-29, 03:27:07 (40.0.40.10)
keto, Unless your line voltage in your area is 115VAC, the 732 will hum like a mo-fo. This is even if it is lightly loaded like in your schmatic. The primarys on the 700 series Hammonds are pretty p .......
440: SET Asylum, Hey! Don't forget the Telefunken RV-218's. (nt) (0.00)
Posted by JLH on 2004-03-24, 09:53:25 (40.0.40.10)
. .......
441: Tube DIY Asylum, Are you for real? (0.00)
Posted by JLH on 2004-03-20, 22:50:00 (171.75.117.78)
You know I’m growing tired of your devil’s advocate and playing dumb games. Anybody that has half a brain will understand the jest of what I am saying. I’m trying to save some of our fellow Inmates .......
442: Tube DIY Asylum, How many double insulated tube amps have you seen? (0.00)
Posted by JLH on 2004-03-20, 11:09:47 (171.75.97.119)
Russ, You are correct for two wire DI devices, but I've yet to meet someone that builds DI tube amps. In addition to fusing both line and neutral, I also switch both with a DPST switch. I've young k .......
443: Tube DIY Asylum, It does it like this. (0.00)
Posted by JLH on 2004-03-20, 10:59:23 (171.75.97.119)
In the event you plug the amp into an outlet that is wired in reverse polarity (i.e. line and neutral are reversed, I've seen it many times) if the neutral wire touches the chassis it will blow the fu .......
444: Tube DIY Asylum, Very, very bad advice. (0.00)
Posted by JLH on 2004-03-18, 09:58:00 (40.0.40.10)
I recommend everyone fuse both line and neutral for safety reasons. The reason why you should fuse both (Like the European standard) is it protects you in the event you plug the amp into an outlet tha .......
445: Tube DIY Asylum, Re: Sanity check - phono preamp design feedback needed (0.00)
Posted by JLH on 2004-03-18, 04:27:58 (40.0.40.10)
Dr. Exotica, This of course is my own personal opinion, but I have a very strong sonic distaste for high Gm tubes ran at low plate current. What’s the point? Look at the link to the data sheet .......
446: High Efficiency Speaker Asylum, 90 degree (nt) (0.00)
Posted by JLH on 2004-03-17, 03:46:40 (40.0.40.10)
. .......
447: K&K Audio / Lundahl Transformers, This OPT has GM70, 75TL, 100TL, 152TL and 250TL written all over it. (nt) (0.00)
Posted by JLH on 2004-03-09, 04:10:53 (40.0.40.10)
;0) .......
448: High Efficiency Speaker Asylum, Re: Tad 4001 diaphragm question (0.00)
Posted by JLH on 2004-03-04, 12:11:21 (40.0.40.10)
Grant, I know this is true for the TAD 2001 diaphragms, but I don't know if it is true for the 4001. Rgs, JLH .......
449: Tube DIY Asylum, Is there an English version? (nt) (0.00)
Posted by JLH on 2004-03-02, 11:56:37 (40.0.40.10)
. .......
450: High Efficiency Speaker Asylum, Re: Tractrix Horn (0.00)
Posted by JLH on 2004-03-02, 04:07:40 (40.0.40.10)
The method I described works every time. But, like I said, it does error on the safe side. In other words your horn will always go down to the desired frequency provided you are not trying to operate .......
451: High Efficiency Speaker Asylum, Re: I've thought about this too... (0.00)
Posted by JLH on 2004-03-02, 04:02:42 (40.0.40.10)
Bill, I’ve done what you suggested with the horn entrance. I agree it helped throat distortion if driven hard, which is in the home environment is never for me. I do notice the discontinuity in soun .......
452: High Efficiency Speaker Asylum, I thought you didn't like the TAD 4002? (0.00)
Posted by JLH on 2004-03-02, 03:47:00 (40.0.40.10)
I do remember you saying you didn't like the TAD 2001, but perfered the Emilar EA175 driver. While we are talking here, can you refresh me what you liked about EA175 over the other 1" comp drivers? Th .......
453: High Efficiency Speaker Asylum, Re: Tractrix Horn (0.00)
Posted by JLH on 2004-03-01, 17:30:31 (67.29.215.119)
Neil, I’ve been making horns for over ten years and have log book that just about has everything I need to refer back to. There is no fixed ratio that one can apply to predict the acoustical roll of .......
454: High Efficiency Speaker Asylum, I've thought about this too... (0.00)
Posted by JLH on 2004-03-01, 17:14:08 (67.29.215.119)
Tim, The main thing stopping us from making "adjustments" to the flare rate of the vintage potted style compression drivers is the fact that the Alnico magnet is in the way. I have thought of takin .......
455: High Efficiency Speaker Asylum, Better take another look. (0.00)
Posted by JLH on 2004-03-01, 04:00:08 (40.0.40.10)
Although a slow taper rate, the TAD 2001, Altec 902, JBL 2441 do not have straight walls. The exit of the phasing plug is smaller in diameter than the throat exit diameter on all these drivers. Rgs, J .......
456: High Efficiency Speaker Asylum, Re: Tractrix Horn (0.00)
Posted by JLH on 2004-02-29, 19:50:39 (171.75.97.121)
Terrones, A TAD 4001 mounted to a 415Hz tractrix will place the acoustical cutoff right around 650Hz. You might want to go a little bigger, say 400Hz, just to be on the safe side. Rgs, JLH ::: TOPIC .......
457: K&K Audio / Lundahl Transformers, Here you go... (0.00)
Posted by JLH on 2004-02-27, 04:21:11 (40.0.40.10)
See link. .......
458: K&K Audio / Lundahl Transformers, Re: interstage phase splitting or parafeed phase splitting (0.00)
Posted by JLH on 2004-02-27, 04:14:09 (40.0.40.10)
Zobsky, Lynn and the Gary's had a thread running a while ago that spoke about why they moved away from parafeed. Their main reason, if I recall correctly, is the parafeed cap colored the sound of th .......
459: SET Asylum, Welborne DRD (nt) (0.00)
Posted by JLH on 2004-02-27, 04:01:42 (40.0.40.10)
;0) .......
460: Vinyl Asylum, 0.7mV = .7 thousandths of a volt, not millionths. (nt) (0.00)
Posted by JLH on 2004-02-19, 10:24:54 (40.0.40.10)
. .......
461: SET Asylum, Re: 6.3v for 10Y /300B Filaments on Larry Moore's 6J5/10Y/300B amp? (0.00)
Posted by JLH on 2004-02-18, 20:15:11 (171.75.97.81)
Jello, The plate load resistor is 10K. Operation point for the 10Y is about 280V, 20ma, -20V. You drop 200V across the plate load resistor and another 20 volts for the bias resistor, this drops you .......
462: SET Asylum, Re: 6.3v for 10Y /300B Filaments on Larry Moore's 6J5/10Y/300B amp? (0.00)
Posted by JLH on 2004-02-18, 03:47:23 (40.0.40.10)
Jello, The 10Y is running off of 6.3VDC and the 300B is running off of 5VDC. Rgs, JLH .......
463: High Efficiency Speaker Asylum, Re: JBL 2410 vs. Altec 802 ? (0.00)
Posted by JLH on 2004-02-13, 03:24:02 (40.0.40.10)
martyh, The Altec 802D is the better of the two drivers. The 2410 has no field of depth to it's imaging IME. I would also recommend that you not use either one of the horns you listed. Instead, get .......
464: High Efficiency Speaker Asylum, Re: Rethm Third without doubt. (nt) (0.00)
Posted by JLH on 2004-02-11, 14:09:21 (67.72.182.161)
The Rethm speakers are quite a bit more dynamic and have a faster more life like speed to them. The Rethm speakers have more punch and stronger upper mid bass energy. The C&C speakers are fine, but I' .......
465: High Efficiency Speaker Asylum, You make me sick! (nt) (0.00)
Posted by JLH on 2004-02-11, 09:48:40 (40.0.40.10)
8^0 .......
466: High Efficiency Speaker Asylum, Rethm Third without doubt. (nt) (0.00)
Posted by JLH on 2004-02-11, 09:45:38 (40.0.40.10)
;0) .......
467: High Efficiency Speaker Asylum, Re: Transformer Attenuators (0.00)
Posted by JLH on 2004-02-06, 03:35:26 (40.0.40.10)
Jonathan, What you are saying about the impedance change with attenuation is true, but that is why you use a dropping resistor in front of the autoformer. You just calculate the reflected impedance .......
468: Vinyl Asylum, That's the first thing I saw too!!! (nt) (0.00)
Posted by JLH on 2004-01-29, 04:04:32 (40.0.40.10)
. .......
469: SET Asylum, Re: SET reliability (0.00)
Posted by JLH on 2004-01-23, 14:09:53 (171.75.97.85)
Swanlake, Considering that Western Electric claims 40,000 hours of life for their 300B, I would say most tubes will out live most of the solid state stuff. I have an old 1950’s Westinghouse radio wi .......
470: SET Asylum, Re: SET reliability (0.00)
Posted by JLH on 2004-01-23, 14:09:53 (171.75.97.85)
Swanlake, Considering that Western Electric claims 40,000 hours of life for their 300B, I would say most tubes will out live most of the solid state stuff. I have an old 1950’s Westinghouse radio wit .......
471: High Efficiency Speaker Asylum, Re: B&C speakers (0.00)
Posted by JLH on 2004-01-23, 14:02:22 (171.75.97.85)
Steve, Small boxes and high efficiency speakers don’t go together. Also, if you want bass you will need to think more toward auto sound style woofers with long Xmax ratings. Pro sound woofers are be .......
472: High Efficiency Speaker Asylum, Re: B&C speakers (0.00)
Posted by JLH on 2004-01-23, 14:02:22 (171.75.97.85)
Steve, Small boxes and high efficiency speakers don’t go together. Also, if you want bass you will need to think more toward auto sound style woofers with long Xmax ratings. Pro sound woofers are bet .......
473: High Efficiency Speaker Asylum, Not 100% sure, but... (0.00)
Posted by JLH on 2004-01-16, 06:14:48 (40.0.40.10)
I believe that Klipsch licensed Vitavox to build the K-horn bass bin in the UK. Kerry Brown (The Vintage Audio Trader) may know for sure if this is true. Rgs, JLH .......
474: High Efficiency Speaker Asylum, ROFLMAO! (0.00)
Posted by JLH on 2004-01-15, 07:23:45 (40.0.40.10)
That's a fucking 6" X 9" car speaker, Ha! Ha! .......
475: Welborne Labs, Your personal opinion on sound differences between TJ45 and various NOS? (nt) (0.00)
Posted by JLH on 2004-01-14, 03:56:57 (40.0.40.10)
;0) .......
476: Tube DIY Asylum, Which TVC are you using? Thanks. (nt) (0.00)
Posted by JLH on 2004-01-13, 16:35:46 (209.244.122.37)
;0) .......
477: High Efficiency Speaker Asylum, Re: Oh -home hifi!- (0.00)
Posted by JLH on 2004-01-12, 18:52:35 (67.29.218.71)
Howdy Mike, Most of the vintage units have Fs’s around 350Hz – 550Hz. Few examples that I’ve measured, TAD 2001 Fs = 360Hz, JBL 2440 Fs = 480Hz, Vitavox Fs = 400Hz, Altec 288C Fs = 490Hz, JBL 2420 F .......
478: High Efficiency Speaker Asylum, Only if you are talking Pro sound apps. (0.00)
Posted by JLH on 2004-01-12, 03:56:23 (40.0.40.10)
Mike, In the home Hi-Fi environment you don’t needs hundreds of watts going to the comp driver. Therefore, the drivers can be used at much lower frequencies than pro sound applications. The only rea .......
479: High Efficiency Speaker Asylum, A 380Hz tractrix will load to 600Hz with 2" throat. (nt) (0.00)
Posted by JLH on 2004-01-12, 03:36:34 (40.0.40.10)
. .......
480: High Efficiency Speaker Asylum, That would be a JBL C40 Harkness (0.00)
Posted by JLH on 2004-01-09, 09:34:20 (40.0.40.10)
djn, The Harkness is one of the better back loaded horn designs from the golden era of sound. For $100 you're not hurting yourself. Add a 1" compression driver midrange horn and you should be able t .......
481: High Efficiency Speaker Asylum, The truth without the sugar coating. LOL! Nice one Tom (nt) (0.00)
Posted by JLH on 2003-12-31, 11:04:02 (40.0.40.10)
. .......
482: Vinyl Asylum, I too know that feeling. Totally sickening... (nt) (0.00)
Posted by JLH on 2003-12-31, 10:59:41 (40.0.40.10)
. .......
483: Tube DIY Asylum, Re: 6D22S max. current specifications? (0.00)
Posted by JLH on 2003-12-30, 03:57:44 (40.0.40.10)
Ray, The 6D22S is a balls to the wall damper diode. One is more than capable of handling 170mA. The 6D22S will handle 500mA steady state in a full wave center tapped circuit without reliability prob .......
484: K&K Audio / Lundahl Transformers, Re: PP TO SE (0.00)
Posted by JLH on 2003-12-19, 12:32:51 (40.0.40.10)
BAU, Only if you use it in a parafeed circuit. The PP OPT is not gapped to handle that much current unbalance. However, you can use the 1663 SE as a PP OPT. The only drawback would be much lower pri .......
485: High Efficiency Speaker Asylum, Re: Can you fold a Tratrix sub horn? (0.00)
Posted by JLH on 2003-12-19, 09:12:29 (40.0.40.10)
Djn, Any horn contour can be folded. However, I would advise you not to use the tractrix for horn sub duty. You would be better served by using the exponential, or more appropriately the hyperbolic .......
486: High Efficiency Speaker Asylum, Re: hey, Chief, it is a "single driver 4" speaker" (0.00)
Posted by JLH on 2003-12-16, 09:39:07 (40.0.40.10)
Yes, Ed I already knew all this. I have built many horn systems over the years, which include the ones I won Most Fabulous of Show at NY Noise 2002. I messed around with back loaded horns and was intr .......
487: High Efficiency Speaker Asylum, Harvey wrote that as a joke, Duh! (nt) (0.00)
Posted by JLH on 2003-12-16, 09:01:35 (40.0.40.10)
. .......
488: High Efficiency Speaker Asylum, A horn that only has a sensitivity of 94dB, what a dubious accomplishment. (0.00)
Posted by JLH on 2003-12-16, 06:04:11 (40.0.40.10)
I'm with you Mike. Those are not "real" horns. Any so called horn with less than 104dB sensitivity is a dubious accomplishment and a complete waste of time. Pretty much puts this horn right there with .......
489: Tube DIY Asylum, Look here---> (0.00)
Posted by JLH on 2003-12-09, 11:12:15 (40.0.40.10)
http://home.att.net/~chimeraone/axialtubesockets.html .......
490: Tubes Asylum, More like Parafeed downgrade. (0.00)
Posted by JLH on 2003-12-09, 09:05:54 (40.0.40.10)
Joseph, Have a look at the K&K Audio thread link below. It should answer why your preamp does not sound as good now. I'm glade to see some of the truth about parafeed finally come out. If I were you .......
491: High Efficiency Speaker Asylum, Re: Nice link - and informative post (0.00)
Posted by JLH on 2003-12-05, 04:11:10 (40.0.40.10)
Yeah Ken, It can be a real bitch to overcome that first few inches between the exit of the phasing plug and the driver's throat exit. The beginning flare rate of any horn is the most important; it s .......
492: High Efficiency Speaker Asylum, Re: Maybe 10KHz - 12KHz...However (0.00)
Posted by JLH on 2003-12-05, 03:58:00 (40.0.40.10)
Tom, I think you should go ahead and try it, I really can't think of any reason why it wouldn't at least improve the lateral coverage. Even with the first 3.5" of the 4001's machined throat being a .......
493: High Efficiency Speaker Asylum, Maybe 10KHz - 12KHz...However (0.00)
Posted by JLH on 2003-12-04, 03:58:27 (40.0.40.10)
If you want to use a fast initial flare on your horn, then you have to use one of the modern compression drivers that do not have a machined throat structure. All the vintage compression drivers th .......
494: SET Asylum, Anything over 1.5W to 2W is going to be from A2. (nt) (0.00)
Posted by JLH on 2003-11-21, 03:42:00 (40.0.40.10)
. .......
495: SET Asylum, Re: What sort of load would you use at that OP? <nt> (0.00)
Posted by JLH on 2003-11-20, 09:30:21 (40.0.40.10)
The whole point of running the 10 hot is 1.) It can handle it just fine, 2.) get the plate resistance down so a 5K to 7.5K OPT can be used. As most of us know, it is very difficult to build a 10K to 1 .......
496: SET Asylum, Just make sure... (0.00)
Posted by JLH on 2003-11-20, 03:48:05 (40.0.40.10)
You run the 10's on the hotter side like Larry does. The 10 doesn't really wake up until its cooking as an output tube. As a driver tube, it is okay to run them a bit cooler. As an output tube, try ru .......
497: High Efficiency Speaker Asylum, What do you guys think about this? Field coils. (0.00)
Posted by JLH on 2003-11-18, 09:25:54 (40.0.40.10)
I found this Web site while doing a search for field coil drivers. See Link. If you think about it, modifying an old potted Alnico compression driver by removing the magnet and inserting a field coil .......
498: High Efficiency Speaker Asylum, What program material you ask? Vinyl Man! ;0) (0.00)
Posted by JLH on 2003-11-17, 18:44:55 (65.58.69.136)
. .......
499: Vinyl Asylum, Analytical Instrument Engineer. (nt) (0.00)
Posted by JLH on 2003-11-17, 10:02:38 (40.0.40.10)
. .......
500: DIY HiFi Forum, Thanks Brian! You have to be the most honest dealer I have ever know. :0) (nt) (0.00)
Posted by JLH on 2003-11-15, 18:36:36 (67.29.215.17)
. .......
Found total of 500 records, Query: , Author: JLH in All Forums, Time: 1 sec.