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1: MagneQuest/Peerless Forum, RE: FS-100 PF and GM70 and 845 amp DIYers (0.00)
Posted by gluca on 2018-06-26, 00:46:40 (194.9.244.44)
B+ was somewhere around 900V and I had 100uF as total C in the PSU. I was not shooting at max power as I have very efficient horns, you'd better plan for A2 to have some extra juice but I guess 15W wo .......
2: MagneQuest/Peerless Forum, RE: FS-100 PF and GM70 and 845 amp DIYers (0.00)
Posted by gluca on 2018-06-25, 14:45:32 (93.70.49.96)
Hi there what mA is your choke rated for? Mine was 100mA and I ran the GM70 at something like 90mA, PSU was full wave 866A and LCLC filter for power tube and full wave 866A LCLC for driver. I used sta .......
3: Tube DIY Asylum, RE: 100TH triode as driver ? (0.00)
Posted by gluca on 2016-12-06, 04:46:17 (165.225.80.90)
I tried it once with a CCS as a driver to GM70 if my memory serves me properly and it was just OK. there are better sounding tubes out there, it was gorgeous thou. .......
4: Tube DIY Asylum, RE: OK (0.00)
Posted by gluca on 2016-12-03, 08:44:39 (2.36.235.103)
well ... I had direct coupled amps that used chokes to load drivers .......
5: Tube DIY Asylum, RE: OK (0.00)
Posted by gluca on 2016-12-03, 08:12:25 (2.36.235.103)
is it a 120Hz or 60Hz? I have 0.25mVrms @ 100Hz (in EU) on my latest 801A direct coupled amplifier ... just finished yesterday (well ... I am missing the definitive 4pin sockets actually). I love dire .......
6: MagneQuest/Peerless Forum, FS-100 PF (0.00)
Posted by gluca on 2016-11-07, 14:02:13 (2.36.200.1)
I was lucky to own it and it sounded great with GM70s, that was a limited run ... I'd go with a 10k load again with a GM70 .......
7: SET Asylum, RE: Replacement of 6N30P driver tubes with 6N6P tubes in my Ayon Crossfire III (0.00)
Posted by gluca on 2016-10-22, 10:54:55 (2.36.203.247)
6N30P and 6N6 cannot be swapped without adjusting the biasing. well, you can but rest assured the replacement tube will not work at an optimum bias and might potentially exceed max ratings ::: TOPIC:: .......
8: Tube DIY Asylum, RE: what schematic? and driver? n/t (0.00)
Posted by gluca on 2016-05-05, 00:39:06 (165.225.80.105)
Mine was 801A choke loaded and direct coupled to parafeed 75TL running at 600V. I loved that amp. .......
9: Tube DIY Asylum, what schematic? and driver? n/t (0.00)
Posted by gluca on 2016-05-04, 13:26:27 (2.36.196.39)
. .......
10: Tube DIY Asylum, thanks! (0.00)
Posted by gluca on 2016-05-04, 11:05:25 (2.36.192.224)
I love those bottles. I am missing them badly. Need to get something rebuilt again .......
11: Tube DIY Asylum, 75TL plate curves (0.00)
Posted by gluca on 2016-05-03, 15:17:23 (2.36.192.224)
I misplaced the file I saved, I downloaded it from a post by Dave Slagle. Anyone have a copy handy? I have been looking here and on intact audio for 1 hour now... meh! Thanks! .......
12: MagneQuest/Peerless Forum, 5x (0.00)
Posted by gluca on 2016-02-03, 10:22:35 (2.36.197.154)
Sorry for the long sad period ... I'd say 5x roughly. .......
13: High Efficiency Speaker Asylum, RE: Onken Suggestions (0.00)
Posted by gluca on 2016-01-12, 13:18:49 (2.36.192.176)
I do have 2001 and love it. it can go down to 1k, maybe 800Hz ... below that would probably be too much of a stretch. A 15" can go up to 600Hz and even 1kHz but it doesn't sound there that good to me. .......
14: High Efficiency Speaker Asylum, RE: Onken Suggestions (0.00)
Posted by gluca on 2016-01-12, 10:21:29 (2.36.192.176)
I would build a classical TAD monitor (15" bass reflex + 2" driver into a 300Hz horn), I didn't like onkens ... very far from being 'tight' and 'fast', sure they go lower than a standard bass reflex b .......
15: MagneQuest/Peerless Forum, RE: nickel vs. pin EXO-46? (0.00)
Posted by gluca on 2016-01-05, 16:38:20 (37.118.196.28)
I love nickel ... I can't explain the difference in words but I just love it. .......
16: MagneQuest/Peerless Forum, RE: Hi-fi via cellphone? (0.00)
Posted by gluca on 2015-12-01, 11:26:19 (94.160.232.123)
I use my iphone with remote to control the macbook feeding my USB dac ... that's all with me. .......
17: MagneQuest/Peerless Forum, FS100PF and 100mA mating choke (0.00)
Posted by gluca on 2015-11-27, 14:53:55 (37.227.0.55)
Hi folks I dismantled my Eimac amp as I no longer need all that much power and I have limited room now. I am not planning to build big amps in the next years so I have these special and limited run FS .......
18: Tube DIY Asylum, I built a ... (0.00)
Posted by gluca on 2015-10-06, 14:11:33 (2.36.213.53)
... headphone amp with 6EW7 and it worked smooth! eventually I replaced the CCS with a choke but the amp itself had no issues whatsoever. g .......
19: Tube DIY Asylum, go bigger (0.00)
Posted by gluca on 2015-09-06, 06:47:30 (2.36.192.87)
i'd suggest to build something different from your 2A3/300B amp and to leave it alone. go for a 801A-GM70 amp. It will be huge (you need regulated filaments) but definitively different from your curre .......
20: MagneQuest/Peerless Forum, RE: audio porn (0.00)
Posted by gluca on 2015-07-04, 00:17:10 (2.36.209.152)
Hi David Yes, grid as plate. PSU is a mixed bridge (393A + Schottky diodes) into a LC filter followed by a CCS + C. Final voltage is 500V, the tube will set its plate voltage and the CCS is dropping 2 .......
21: MagneQuest/Peerless Forum, Q&A (0.00)
Posted by gluca on 2015-07-01, 15:04:27 (2.36.203.208)
Driver for 801A amp: none, one tube only. I was using a 1:4 (or was it a 1:8) step up transformer but I removed it ... I just need mW here EIMAC amp: too hot and too heavy to move them 3 floors upstai .......
22: MagneQuest/Peerless Forum, RE: audio porn (0.00)
Posted by gluca on 2015-06-20, 10:28:23 (2.36.193.165)
well ... xover. I am using a Beringher CX2310 to drive a VT52 differential amp (IT transformer, tamuras) and a 801A spud amp. Midbass and mid/high crossed with 6dB/oct, so just a cap, inductor and a h .......
23: MagneQuest/Peerless Forum, audio porn (0.00)
Posted by gluca on 2015-06-20, 06:36:49 (2.36.193.165)
My latest speakers. 80Lt sealed sub up to 100Hz (TAD TL1603) big tractrix midbass horn (TAD TM1201) 100-600Hz JMLC-IWATA mid hort (TAD 4001) 600- xxx fostex T900A tweeter or 1" driver TD2001 with smal .......
24: MagneQuest/Peerless Forum, I love these 801A line stages (0.00)
Posted by gluca on 2015-06-04, 14:18:56 (2.36.194.205)
congrats, happy you are enjoying it. g .......
25: MagneQuest/Peerless Forum, I WANT that cycling jersey... (0.00)
Posted by gluca on 2015-05-13, 15:28:02 (2.36.214.103)
hey ... seriously, I want one. .......
26: MagneQuest/Peerless Forum, RE: Teaser Post (0.00)
Posted by gluca on 2015-02-17, 10:08:21 (2.36.195.15)
I WANT A TL404 WITH NICKEL LAMS!!! AH! .......
27: MagneQuest/Peerless Forum, very nice! (0.00)
Posted by gluca on 2015-01-07, 11:53:52 (2.36.196.135)
this simple and somehow retro look is gorgeous .......
28: MagneQuest/Peerless Forum, Happy BDay MQRacing! (0.00)
Posted by gluca on 2014-12-16, 09:47:45 (2.36.196.135)
Hey! It happens once per year, I hope you are enjoying this day g .......
29: SET Asylum, Q (0.00)
Posted by gluca on 2014-12-06, 14:30:51 (2.36.213.107)
Paul I tried this design with zeners and VR gas tubes to bias the upper tube (replacing the 3k/20W resistor and no bypass caps clearly) ... any experience with this variant? g .......
30: MagneQuest/Peerless Forum, I know ... but (0.00)
Posted by gluca on 2014-12-05, 10:52:25 (2.36.213.107)
but ... I keep dreaming .......
31: MagneQuest/Peerless Forum, I know ... but (0.00)
Posted by gluca on 2014-11-13, 11:31:39 (2.36.220.43)
... but I just fell in love with nickel cores. what can I do? nothing can stop love .......
32: MagneQuest/Peerless Forum, when? (0.00)
Posted by gluca on 2014-11-11, 13:33:09 (2.36.207.1)
when a nickel core TL404? .......
33: Tube DIY Asylum, matched? (0.00)
Posted by gluca on 2014-10-14, 13:58:29 (2.36.198.30)
where are the results from tube tester? .......
34: MagneQuest/Peerless Forum, very nice (0.00)
Posted by gluca on 2014-10-06, 10:42:52 (2.36.209.44)
clean and simple. If I may ask ... AC or DC filament? .......
35: MagneQuest/Peerless Forum, Schematics (0.00)
Posted by gluca on 2014-09-14, 14:07:23 (2.36.194.151)
much simpler and with lower gain than PJ's. I used to have a 4th box with a S&B multitapped transformer to control the volume ... I sold it eventually as I embedded the volume into my pre-phono. It is .......
36: MagneQuest/Peerless Forum, 211 preamp (0.00)
Posted by gluca on 2014-09-12, 12:59:39 (2.36.194.151)
Mikey you mentioned a 211 preamp a few posts below ... here it is ;-) 3 boxes ... bottom shelf. Running since ages and happy as a baby at xmas. Solid state CCS and all nickel 10k B7 at the output. .......
37: SET Asylum, and ... (0.00)
Posted by gluca on 2014-06-24, 13:43:51 (91.253.18.164)
... I have been running the same 211s, 801As and 75TLs on a daily basis with multiple on/off per day for years .......
38: MagneQuest/Peerless Forum, RE: TL 404 run? (0.00)
Posted by gluca on 2014-06-09, 14:31:06 (2.36.223.65)
silver? nickel? .......
39: MagneQuest/Peerless Forum, yummi! (0.00)
Posted by gluca on 2014-05-06, 14:38:48 (2.36.208.71)
have fun building your next amp .......
40: Tube DIY Asylum, bad soldering? (0.00)
Posted by gluca on 2014-03-31, 11:28:52 (2.36.218.139)
it happens. .......
41: High Efficiency Speaker Asylum, More ribbons (0.00)
Posted by gluca on 2014-03-20, 12:53:57 (2.36.204.84)
I eventually sold the 2001's to secure resources for tweeters, I know I will miss them as I am missing a pair of JBL 2482's sold time ago, but, hey!, I cannot pile parts like an audio-fetishist. I am .......
42: High Efficiency Speaker Asylum, What RAAL? (0.00)
Posted by gluca on 2014-03-20, 08:08:53 (128.45.48.184)
Lazy ribbons? .......
43: High Efficiency Speaker Asylum, I agree (0.00)
Posted by gluca on 2014-03-17, 04:22:53 (91.253.7.108)
I agree, they will soon on sale. i am gathering comments from users on RAAL lazy ribbons. I am pretty familiar with all the fostex's .......
44: High Efficiency Speaker Asylum, New measurement (0.00)
Posted by gluca on 2014-03-16, 10:54:30 (2.36.223.92)
Thanks all I tuned the xover a bit (smaller hi pass cap), played a bit with physical alignment and I think I found a result I can settle with. I will consider to add a super tweeter clocking in at .......
45: High Efficiency Speaker Asylum, RE: Help me with these horns (0.00)
Posted by gluca on 2014-03-16, 10:51:17 (2.36.223.92)
nearfield it would and it actually does. I am considering adding a super tweeter, see my new measurement (upper post) thanks .......
46: High Efficiency Speaker Asylum, Nearfield (0.00)
Posted by gluca on 2014-03-14, 01:02:16 (31.188.224.60)
Thanks John They are nearfield no xover .......
47: High Efficiency Speaker Asylum, unfiltered (0.00)
Posted by gluca on 2014-03-13, 16:22:03 (2.36.201.17)
so, it seems the 2001 is not 8ohm. a 7.3uF leaves bandwidth undisturbed down to 1kHz (compare to filtered measurement in previous posts) woofer mid high .......
48: High Efficiency Speaker Asylum, RE: more data (0.00)
Posted by gluca on 2014-03-13, 13:31:03 (94.167.244.95)
I think there is something wrong with the 2001 highpass, i'll post unfiltered measurements later tonite .......
49: High Efficiency Speaker Asylum, more data (0.00)
Posted by gluca on 2014-03-13, 12:05:22 (2.36.201.17)
Thanks for all your inputs and suggestions. RAAL: wondering how I can integrate it, triamping?? not really willing to attenuate horns as RAALs are rated at 92dB/W/m. FOSTEXs: I was considering the sma .......
50: High Efficiency Speaker Asylum, Help me with these horns (0.00)
Posted by gluca on 2014-03-12, 15:51:43 (2.36.213.216)
Hey I am tuning my horn system and need advices. I currently have a TAD 1603 loaded into a 170LT/35Hz bass reflex, a 300Hz JMLC-Iwata horn with a TAD 4001 and a 1kHz JMLC horn with TAD 2001; xover is .......
51: Tube DIY Asylum, you need a higher voltage PSU (0.00)
Posted by gluca on 2014-03-03, 12:29:17 (2.36.222.174)
that is the first step .......
52: Tube DIY Asylum, Yes (0.00)
Posted by gluca on 2014-01-27, 12:28:40 (93.146.145.130)
Hi Paul I was suggesting GSH to give the CCS a try: it sets direct current in the OPT, biases the tube and enhance PSRR to a great extent. AC current, the signal, is not disturbed by the CCS. I co .......
53: Tube DIY Asylum, My 801A amp (0.00)
Posted by gluca on 2014-01-27, 10:50:36 (93.146.145.130)
Hi Paul my 801A amp has a CCS feeding the output transformer (and a final cap before it). Now listening to Jaco Pastorius with that very amp. G .......
54: High Efficiency Speaker Asylum, You will be missed! (0.00)
Posted by gluca on 2013-12-31, 03:18:05 (94.161.30.46)
Goodbye JM! Thanks for all your passion, I will enjoy your horns with more gratitude now. G .......
55: MagneQuest/Peerless Forum, Get them while you can! (0.00)
Posted by gluca on 2013-12-17, 10:31:42 (93.71.8.3)
Right now I am listening to my amp with a couple VT52's in a differential stage loaded by Ni/M4 565's. Driver is a 6CG7 SRPP where I swapped the classical 500ohm resistor with a EXO99 for more yummy y .......
56: High Efficiency Speaker Asylum, RE: Horns for TD-4001 (0.00)
Posted by gluca on 2013-11-22, 14:07:59 (188.216.117.24)
I understand the point you are making and actually TAD monitors are two ways and that was my very initial idea but at the end I preferred 3 ways. You should like the combo 1601+4001 crossed at 600Hz m .......
57: High Efficiency Speaker Asylum, RE: Horns for TD-4001 (0.00)
Posted by gluca on 2013-11-21, 15:42:08 (188.216.117.24)
Hey Michael my current setup is TAD1603 in 170Lt bass reflex tuned to 35Hz, TAD4001 in 300Hz Iwata, TAD2001 in 1kHz tractrix. I crossed 1603 to 4001 at various freqs and the best I found is 600Hz, ove .......
58: Tube DIY Asylum, use xls (0.00)
Posted by gluca on 2013-10-17, 10:28:48 (188.216.119.195)
there is the file we set up a while ago http://www.intactaudio.com/forum/viewtopic.php?t=316 or the one by voltsecond http://www.siteswithstyle.com/Voltsecond/Parafeed_fun/Parafeed_fun.html ::: TOPIC: .......
59: MagneQuest/Peerless Forum, RE: MQ at RMAF 2013 (0.00)
Posted by gluca on 2013-10-10, 09:38:59 (188.216.119.195)
Nice looking horns and very interesting bass module kudos! .......
60: SET Asylum, Close the gap (0.00)
Posted by gluca on 2013-09-25, 14:04:53 (188.216.119.195)
Go parafeed as WE did many years ago. My big transmitting triodes amplifier with MQ ungapped cores went down to 10Hz. OK, there is a little cheating there as the LCL is a resonant low freq cell. I hav .......
61: High Efficiency Speaker Asylum, yummy! they look gorgeous n/t (0.00)
Posted by gluca on 2013-07-26, 13:23:38 (188.216.114.16)
. .......
62: MagneQuest/Peerless Forum, and it looks soooo coooool n/t (0.00)
Posted by gluca on 2013-06-26, 10:57:38 (188.216.114.16)
congrats! .......
63: MagneQuest/Peerless Forum, RE: B7 - ) 71A -) 300B (0.00)
Posted by gluca on 2013-02-26, 10:12:53 (188.216.115.123)
if you go for two separare PSU's then stack them and direct couple the two stages (you don't need the RIT) .......
64: Tube DIY Asylum, I do not completely agree (0.00)
Posted by gluca on 2013-02-12, 10:15:32 (188.216.115.123)
IMHO where parafeed transformers do their best is at high freqs ... you have a smaller core, smaller windings, lower Cp. winding a choke is somehow simpler than a transformer and as Paul pointed it ge .......
65: Tube DIY Asylum, I second that (0.00)
Posted by gluca on 2013-02-11, 14:52:53 (188.216.115.123)
I'd go, and I went many many times, for a parallel feed. A small, Ni lams, ungapped transformer will be hardly surpassed by a series feed gapped transformer. .......
66: MagneQuest/Peerless Forum, that was quick! (0.00)
Posted by gluca on 2013-01-20, 12:50:06 (188.216.115.123)
Sold to the gentleman from NJ. It took 2 mins for the TL404s to find a new home. Mike, there is most probably a real market demand for these ugly fugly autoformers ... maybe on EI cores? .......
67: MagneQuest/Peerless Forum, TL404 for sale (0.00)
Posted by gluca on 2013-01-20, 10:39:57 (188.216.115.123)
So I have this pair of TL404's and they are from the first batch made by Mike missing the 10 and 4 ohm taps (see the original post by Mike). I dismantled my DAC and they have been sitting in my parts .......
68: MagneQuest/Peerless Forum, Happy BDay MSL (0.00)
Posted by gluca on 2012-12-16, 13:25:25 (188.216.123.170)
:-) gianluca .......
69: MagneQuest/Peerless Forum, consider this ... (0.00)
Posted by gluca on 2012-11-21, 12:58:25 (79.48.35.5)
consider the EXO99, I am using it as a PP plate choke in my latest amp. it would work at the cathodes as well. .......
70: MagneQuest/Peerless Forum, Yes, you can ... (0.00)
Posted by gluca on 2012-10-23, 10:56:28 (188.216.123.170)
... but you would toss more $$$ on the amp and you would not have any more what I like: the upped CCS+zeners kinda work as shunt regulated PSU for the lower differential pair. zeners can be a bit nois .......
71: MagneQuest/Peerless Forum, a few runs on my oscilloscope ... (0.00)
Posted by gluca on 2012-10-20, 01:37:04 (188.216.123.170)
Thanks Bas. I built the prototype in almost nothing ... maybe a couple evenings and all went OK at the first power up. Kinda scared at first turn on but it looks really stable and reliable so far. Pro .......
72: MagneQuest/Peerless Forum, RE: details (0.00)
Posted by gluca on 2012-10-15, 12:31:34 (188.216.123.170)
the project started with EL84s and evolved towards VT52 as i found a nice quartet along the way .......
73: MagneQuest/Peerless Forum, details (0.00)
Posted by gluca on 2012-10-13, 10:59:45 (188.216.123.170)
Zeners are 15x16V each ... mind the wattage as they are heating quite a lot. I need to fix this bug, mine are boiling. EXO99 is used as push-pull choke or as if it was a primary of a interstage transf .......
74: MagneQuest/Peerless Forum, My latest amp ...a push pull eventually (0.00)
Posted by gluca on 2012-10-13, 10:47:02 (188.216.123.170)
Here it is. Now playing. There is not much to say about it ... a couple of differential pairs direct coupled and stacked over a string of zener. That's something I made in other amps before this .......
75: High Efficiency Speaker Asylum, so ... (0.00)
Posted by gluca on 2012-10-06, 12:16:22 (188.216.123.170)
you do not even breath on the chair to stay exactly on the sweet spot? nice rig! congrats! .......
76: High Efficiency Speaker Asylum, RE: AutoTech Iwata 300 (0.00)
Posted by gluca on 2012-10-06, 00:22:49 (188.216.123.170)
You'd better ask JMLC directly or Lucasz at autotech ... I never listened to that specific 300Hz E-JMLC horn. Sound is really 'natural' and 'neutral' with this set up, I'd say. gianluca .......
77: High Efficiency Speaker Asylum, thanks (0.00)
Posted by gluca on 2012-10-04, 14:28:01 (188.216.123.170)
I can say this horn horn sounds really neutral and 'not in your face' as some pro/vintage horns. .......
78: High Efficiency Speaker Asylum, here it comes mine (0.00)
Posted by gluca on 2012-10-04, 13:18:01 (188.216.123.170)
TAD 1603 into a 170LT bass reflex tuned at 35Hz TAD 4001 into a 300Hz Iwata horn modified by JMLC and made by Autotech TAD 2001 into a 1000Hz JMLC horn made by Autotech xovers 6dB/oct at 550Hz and .......
79: MagneQuest/Peerless Forum, that sounded good to me (0.00)
Posted by gluca on 2012-10-03, 12:33:47 (188.216.123.170)
a B7 is still working as a step-up for in a DHT amp I made some years ago. .......
80: Tube DIY Asylum, RE: Catastrophe in Montana, Dennis (0.00)
Posted by gluca on 2012-08-31, 14:53:14 (188.216.123.170)
I wish him a quick return to a normal life. What a disasters! Thanks God only minor injuries to other people as per your link Gianluca .......
81: Tube DIY Asylum, step down (0.00)
Posted by gluca on 2012-06-23, 23:24:18 (93.71.96.160)
all my preamps/sources have step-down transformers at the output ... tipically 10K:600 anyway there was someone somewhere who built a 300B spud amp and had no problems, I misplaced the URL but that si .......
82: Tube DIY Asylum, RE: Elegant...brilliant...I suppose you have very high (0.00)
Posted by gluca on 2012-06-23, 10:36:43 (93.71.96.160)
TAD4001 into iwata JMLC 300Hz TAD2001 into JMLC 1000Hz Bass bin is running a TAD1603 .......
83: Tube DIY Asylum, RE: Elegant...brilliant...I suppose you have very high (0.00)
Posted by gluca on 2012-06-22, 11:45:04 (93.71.96.160)
very high efficiency ... here it is. LL7903 is wired 1:4 if my memory serves me correctly. I do not need that much gain ciao .......
84: Tube DIY Asylum, RE: Schematics? (0.00)
Posted by gluca on 2012-06-22, 11:43:14 (93.71.96.160)
Well ... I do not have a proper schematic handy but this gives you an idea. Batteries are not there at the grid, I am using zeners at the cathode. .......
85: Tube DIY Asylum, Best wishes Mark! (0.00)
Posted by gluca on 2012-06-21, 14:00:49 (93.71.96.160)
thanks for all your posts, I hope everything gets better soon .......
86: Tube DIY Asylum, 801A spud here (0.00)
Posted by gluca on 2012-06-21, 13:58:13 (93.71.96.160)
LL7903 at the input and a LL2735B at the output, a string of zeners is biasing the tube at 30mA. rod coleman's heaters, grid-as-plate WE393A + SS diodes into LC and a CCS in the PSU to get rid of ever .......
87: High Efficiency Speaker Asylum, RE: from scratches (0.00)
Posted by gluca on 2012-03-20, 11:35:07 (93.71.82.100)
no I am keeping my TADs and horns; i am just building a new system for my parents place (where I go very often and it is the place I call home) .......
88: High Efficiency Speaker Asylum, Forte (0.00)
Posted by gluca on 2012-03-19, 16:06:00 (93.71.82.100)
is it ported? .......
89: High Efficiency Speaker Asylum, nice one (0.00)
Posted by gluca on 2012-03-18, 15:58:38 (109.115.177.67)
congrats, they look gorgeous. .......
90: High Efficiency Speaker Asylum, from scratches (0.00)
Posted by gluca on 2012-03-18, 12:59:25 (109.115.255.245)
... I believe I will stick to the original plan (minus the horn/tweeter as I will use a Iwata I have). two ways + sub if I'll need that. Any pic around about those CW1526 by BC? Price looks really gre .......
91: High Efficiency Speaker Asylum, RE: considering a la scala clone (0.00)
Posted by gluca on 2012-03-18, 03:52:35 (176.247.188.179)
thanks all for the many replies (I was and I am not very familiar with la scalas). I'll look onto those Crites clones and I also found a pair of links to some mods discussed of the klipsch forum gian .......
92: High Efficiency Speaker Asylum, hehehehe (0.00)
Posted by gluca on 2012-03-18, 02:45:09 (176.247.188.179)
I love those tad's ;-) .......
93: High Efficiency Speaker Asylum, considering a la scala clone (0.00)
Posted by gluca on 2012-03-17, 10:21:37 (176.247.188.179)
... what modern woofer should I look at? I'd love to give the faital speakers a try (well ... being myself italian). tks gluca .......
94: MagneQuest/Peerless Forum, RE: Nickel TL 404 (0.00)
Posted by gluca on 2012-03-17, 10:14:35 (176.247.188.179)
and it is so huuuuugly ... a nice piece of iron, the best so far. .......
95: MagneQuest/Peerless Forum, cobalt or nickel (0.00)
Posted by gluca on 2012-03-04, 14:52:57 (93.71.79.230)
maybe silver windings? .......
96: SET Asylum, 801A here (0.00)
Posted by gluca on 2012-02-14, 10:22:19 (93.71.79.230)
Paul ... I just assembled a 801A spud amp. just that tube and an input tranny 1:8 (to be installed) sweet. .......
97: MagneQuest/Peerless Forum, anybody using this? (0.00)
Posted by gluca on 2012-02-10, 13:03:29 (93.71.79.230)
just wondering as I am planning to buy one .......
98: High Efficiency Speaker Asylum, never enough ... (0.00)
Posted by gluca on 2012-01-25, 13:46:39 (93.71.109.82)
... keep them going .......
99: MagneQuest/Peerless Forum, Why? Why? Why? (0.00)
Posted by gluca on 2012-01-19, 12:30:16 (93.71.109.82)
for God's sake, why one should want DC current in a trasformer? WHY? .......
100: Tube DIY Asylum, RE: DC coupled GM70 (0.00)
Posted by gluca on 2011-12-27, 16:13:32 (109.113.156.96)
I started using those stacked supplies years ago in one of the many versions of my main amps (well ... actually I suggested Andrea to stack the PSUs in that very amp in a discussion over DIYAUDIO). My .......
101: MagneQuest/Peerless Forum, I CAN SEE ... (0.00)
Posted by gluca on 2011-12-19, 10:01:51 (93.71.72.59)
... YOUR FUTURE AND I CAN READ INTO YOUR BRAINS. buahahahha .......
102: MagneQuest/Peerless Forum, RE: changed URL ... (0.00)
Posted by gluca on 2011-12-18, 14:56:21 (93.71.72.59)
TAD 1603 (170lt, 35Hz bass reflex) TAD 4001 IWATA/JMLC 300 by autotech TAD 2001 JMLC 1000 by autotech xover is 6dB/oct at 550 and 3000 Hz. yes pretty expensive stuff ... I am still selling some of my .......
103: MagneQuest/Peerless Forum, changed URL ... (0.00)
Posted by gluca on 2011-12-18, 11:27:37 (93.71.72.59)
... .......
104: MagneQuest/Peerless Forum, work in progress ... (0.00)
Posted by gluca on 2011-12-18, 04:53:34 (93.71.72.59)
My new horn speakers .......
105: MagneQuest/Peerless Forum, Hey!! You are buying us a beer! (0.00)
Posted by gluca on 2011-12-16, 09:31:23 (93.71.72.59)
Happy BDay Mr MQ .......
106: MagneQuest/Peerless Forum, RE: TFA-2004 cobalt in a JFL Horus (0.00)
Posted by gluca on 2011-12-11, 04:08:08 (109.115.170.87)
HUM! All I need for xmas is a cobalt and silver TL404! a pic??! I like audio-porno. .......
107: MagneQuest/Peerless Forum, Filament (0.00)
Posted by gluca on 2011-12-11, 04:06:23 (109.115.170.87)
Mike take care of the filament. You really need a LCL filter or LCLCL (yes a big choke before and close to the filament) or an active regulator from Rod Coleman or Guido Tent. That will make a huge di .......
108: Tube DIY Asylum, was... (0.00)
Posted by gluca on 2011-12-08, 11:00:25 (109.115.203.16)
It was 900V/100mA into a 10K output transfomer. .......
109: Tube DIY Asylum, Yes, 801 has higher Rp ... (0.00)
Posted by gluca on 2011-12-08, 07:15:24 (109.113.248.64)
... so what? if you want low impedance just forget tubes and go for a mosfet drive. as long as you don't go into A2 or close to A2 difference would be negligible (other things do matter much more). BU .......
110: MagneQuest/Peerless Forum, RE: Pong MQRacing (0.00)
Posted by gluca on 2011-12-07, 23:45:12 (109.115.149.88)
Gain is (almost) the same from anode or mu-out. mu-out has a lower impedance but the cascode will not offer the high PSRR and noise immunity it gives from the anode-out. one of the reasons I like to C .......
111: Tube DIY Asylum, EML 20A --) 801A --) GM70!! n/t (0.00)
Posted by gluca on 2011-12-07, 13:00:31 (109.112.127.169)
. .......
112: MagneQuest/Peerless Forum, Pong MQRacing (0.00)
Posted by gluca on 2011-12-07, 12:58:17 (109.112.127.169)
Ciao Mike yes, water babies is my line stage. It was born with a 801A but I switched to 211 after a while. I also found a couple of eimac 75THs but sold them before I could find any spare time to try .......
113: MagneQuest/Peerless Forum, CC cores again I suppose? (0.00)
Posted by gluca on 2011-11-25, 09:59:11 (93.71.86.164)
I'd swap my copper TL404s for a silver edition ... yummi. .......
114: MagneQuest/Peerless Forum, TL404 (0.00)
Posted by gluca on 2011-11-22, 14:54:00 (93.71.86.164)
I have your last pair ... any chance you are winding more of them with some nickel or silver? they are so yummy ... that would be the time I finally buy a silver transformer. .......
115: High Efficiency Speaker Asylum, silly question about iron and drivers (0.00)
Posted by gluca on 2011-10-03, 13:14:13 (89.118.226.161)
ok, I feel a bit embarrassed as the question might be a very basic one but, well ... here it is! I am trying to build a frame to support my horns and drivers and it will most probably be made joining .......
116: MagneQuest/Peerless Forum, what else ... (0.00)
Posted by gluca on 2011-09-14, 12:42:02 (89.118.226.161)
ah! those guys in the old days knew how to do things ... .......
117: MagneQuest/Peerless Forum, here it is, sir (0.00)
Posted by gluca on 2011-09-04, 10:55:04 (69.174.87.28)
You will also spot the old 304TL amp (now dismantled and rebuilt with 75TL in a 4 chassis amp). The blue glowing puppies are WE393 thyratrons and the right box is for the filament supply. I bow my hea .......
118: MagneQuest/Peerless Forum, RE: How to use WE101D in a preamp? (0.00)
Posted by gluca on 2011-09-04, 09:33:21 (207.250.126.115)
It looks OK. You might want to use LEDs in the cathode or maybe a filament biasing (use the filament current flowing on a smaller resistor) to get rid of the RC bias. It is a matter of personal taste, .......
119: MagneQuest/Peerless Forum, better go for a 10K:500 or more (0.00)
Posted by gluca on 2011-09-03, 20:44:03 (207.250.126.115)
I believe B7 (it happens to be one of my fav line out transformers) is available also as 15k:500 step down ratio. The difference among all other things is the primary inductance being higher in latter .......
120: MagneQuest/Peerless Forum, RE: How to use WE101D in a preamp? (0.00)
Posted by gluca on 2011-09-03, 10:32:40 (207.250.126.115)
Mike might chime in and comment on my words below ... I believe you have basically two ways to build that preamp: 1) use a solid state CCS and wire the whole thing as a mu-follower so to offer a lower .......
121: MagneQuest/Peerless Forum, RE: PP 6EM7 schematic (0.00)
Posted by gluca on 2011-08-30, 17:10:50 (207.250.126.115)
No CCS' this time? I loved the 6EW7 in my headphone amp. Planning to rebuild a flea power amp out of it one day, but I want a super duper core transformer (maybe silver windings too ... mike tempted m .......
122: MagneQuest/Peerless Forum, Congrats & question (0.00)
Posted by gluca on 2011-07-26, 11:29:23 (69.174.87.28)
Hey Gordon congrats on the beaudddiful products you are manufacturing and the impressive leap in ADC/DAC technology (and without dismissing the old tubes ...) Question: what should I expect from silv .......
123: Music Lane, noted (0.00)
Posted by gluca on 2011-07-25, 17:28:14 (208.102.126.130)
... If memory serves me right, Nina had to leave USA because of her strong position against Vietnam war. .......
124: Music Lane, Nina Simone (0.00)
Posted by gluca on 2011-07-24, 11:09:08 (208.102.126.130)
I only own a 'best of' and I'd love to buy myself some live concerts. Any suggestion from experts? .......
125: MagneQuest/Peerless Forum, 230V 50Hz ... (0.00)
Posted by gluca on 2011-07-21, 18:40:06 (208.102.126.130)
... all over EU. oh! those SMPS so handy when you travel. .......
126: Tube DIY Asylum, I find 300B boring. n/t (0.00)
Posted by gluca on 2011-07-21, 14:31:02 (208.102.126.130)
. .......
127: MagneQuest/Peerless Forum, RE: some brief specs for R-080, R-160 and R-196 (0.00)
Posted by gluca on 2011-07-21, 14:29:12 (208.102.126.130)
I assume primaries are 110V ... .......
128: Tube DIY Asylum, You need gain... (0.00)
Posted by gluca on 2011-07-16, 14:37:27 (208.102.126.130)
I have a 8x PCM1704k DAC running with a 11ohm IV resistor and a cinemag CMQEE3440 150:50k step up transformer and a SRPP of 6CG7. Now ... the output transformer is not available anymore but you can su .......
129: Tube DIY Asylum, RE: Advice sought, given three possible tube types for the output on a DAC which would you choose in this scenario (0.00)
Posted by gluca on 2011-07-15, 22:00:40 (208.102.126.130)
SRPP of 6SN7 .......
130: Tube DIY Asylum, RE: Any one ever try something like this ... (0.00)
Posted by gluca on 2011-07-14, 19:25:45 (208.102.126.130)
The driver is just like my headphone amp (now dismantled) it is really stable and reliable. You'd better use just a 6EW7 (both the sections). I used a CCS on top of the higher triode (low gain section .......
131: High Efficiency Speaker Asylum, RE: not exactly them (0.00)
Posted by gluca on 2011-06-01, 05:19:49 (192.88.212.44)
I'll use stud type. Best would be silicone gel studs but cost is really impressive so I'll buy something cheaper. When I say bet I mean the stud with the highest damping at the lowest freq but I do be .......
132: High Efficiency Speaker Asylum, not exactly them (0.00)
Posted by gluca on 2011-05-31, 06:29:03 (216.68.186.72)
but other industry standard vibration dampeners you can find on vibrationmounts.com They start dampening from 15hz usually which is ok for a mid/high transducer. You need to know the mass of the syste .......
133: High Efficiency Speaker Asylum, planning to use (0.00)
Posted by gluca on 2011-05-30, 17:18:58 (216.68.189.243)
i'll use vibramounts to dampen bass bin vibrations .......
134: High Efficiency Speaker Asylum, RE: A little too spaced out vertically for me (0.00)
Posted by gluca on 2011-05-27, 19:24:16 (216.68.186.182)
won't the shorter horn be shooting at the longer and be 'in its shade'? that's where the distance between the horns is coming from. .......
135: High Efficiency Speaker Asylum, Ideas for a frame for my horns (0.00)
Posted by gluca on 2011-05-27, 11:15:33 (192.88.212.34)
I decided to try a 2" driver for mids and a 1" taking over at 3k to cover highs so the question that came to my mind is how to build a suitable frame to support both of them. See attached pic (dime .......
136: High Efficiency Speaker Asylum, curiosity killed the cat (0.00)
Posted by gluca on 2011-05-21, 16:19:47 (74.83.201.95)
... any specific post/discussion over the cat's forum you are referring to? tks gianluca .......
137: High Efficiency Speaker Asylum, Impedance vs freq not handy ... (0.00)
Posted by gluca on 2011-05-21, 12:47:49 (74.83.201.95)
... but I remember I saw it somewhere on the WWW. I'll try to listen to a couple systems before commit into buying something. Maybe 4 ways is the solution ... kind scared of the complexity, it all sta .......
138: High Efficiency Speaker Asylum, That ... (0.00)
Posted by gluca on 2011-05-20, 13:58:22 (192.88.212.34)
That was my initial idea (T500mkII) but the person I spoke with the last days seemed so happy with 2001's to make me rethink again plus there are the various positive comments by Rick. What freq are y .......
139: High Efficiency Speaker Asylum, RE: Is it my ears or the autoformer? (0.00)
Posted by gluca on 2011-05-20, 11:47:46 (192.88.212.34)
I have felt and that is one thing I plan to do on 4001s, not sure about bypassing the connectors ... I'd prefer to maintain the drivers as original as possible to safeguard the reselling value. below .......
140: High Efficiency Speaker Asylum, I do remember your old post ... (0.00)
Posted by gluca on 2011-05-20, 09:54:14 (192.88.212.34)
... and an other user recently reported me he is using JBL2441+TAD2001 and is happily living with them. not sure about his xover freq. so, you are using 4001 from 500 (?) to 2k and 2001 from there upw .......
141: High Efficiency Speaker Asylum, calling TAD 2001 users (0.00)
Posted by gluca on 2011-05-20, 06:57:13 (192.88.212.34)
Anybody using TAD 2001 to cover the top end? I am still looking for a tweeter to mate the TAD 4001 + Iwata and I saw some are using 2001 with a small horn. Ideally I'd cross it at 5kHz. Other options .......
142: SET Asylum, Cinemag or Magnequest. (0.00)
Posted by gluca on 2011-05-18, 17:33:38 (74.83.201.95)
nickel lams. .......
143: MagneQuest/Peerless Forum, answers (0.00)
Posted by gluca on 2011-05-11, 19:17:38 (74.83.201.95)
Now I'll tell you a secret. I have been in the audio hobby for not a long time but I have my own secrets and this is one of the most private to me. That carton is not a generic carton because I take c .......
144: MagneQuest/Peerless Forum, RE: more eyecandies ... my last DAC (0.00)
Posted by gluca on 2011-05-10, 20:28:40 (74.83.201.95)
well ... actually I posted the pic just to make funny of me but assembling the DAC made me understand how the layout can be improved and where to move parts on the PCB to make things smarter (did I re .......
145: MagneQuest/Peerless Forum, more eyecandies ... my last DAC (0.00)
Posted by gluca on 2011-05-09, 19:19:22 (74.83.201.95)
buahhahahahhaha ... in a carton ... The DAC (the buffalo II) is sporting a 6H30 into parafeed Ni beeseven, the tube is loaded with a cascoded FETs CCS and biased with a 6.2V zener. PSU is 6X5GT and cL .......
146: Tube DIY Asylum, RE: OTK (0.00)
Posted by gluca on 2011-05-09, 07:06:40 (192.88.212.32)
I bought some gold grid 6N6Ps made in 1982 by Novosibirsk. 6 of them. 6N30 prices are sky rocket high ... that's crazy! I paid lower prices for my super rare eimacs. mah!? I see I can bias 6N6, ECC99 .......
147: Tube DIY Asylum, OTK (0.00)
Posted by gluca on 2011-05-08, 18:16:48 (74.83.201.95)
OTK is the sign that the tube (or any other item in CCCP) passed more severe quality checks. Russian friends of mine told me they used to buy only OTK marked goods, all others were junk. I liked 6N6 w .......
148: Tube DIY Asylum, RE: suggest me a tube (0.00)
Posted by gluca on 2011-05-08, 07:29:11 (74.83.201.95)
The only 6H30 I have is by sovtek and recent, NOS' are pretty much unaffordable to me given the crazy prices ppl are paying for. I have used ECC99, 6H6P, 6H30 in the past and looking for something new .......
149: Tube DIY Asylum, suggest me a tube (0.00)
Posted by gluca on 2011-05-07, 17:41:04 (74.83.201.95)
Dual triode, noval socket, to be biased at 9V at the cathode, mu 10-30, current and plate voltage can be adjusted freely. I Have 6H30 and 12BH7 to try but I'd like to swap more tubes (in my new DAC) .......
150: Tube DIY Asylum, RE: D.C.M.B (Direct Coupling Modulated Bias) (0.00)
Posted by gluca on 2011-05-03, 09:02:34 (192.88.212.44)
See link ... (I don't understand why such a long name ...) Mine uses 801A and 75TL. .......
151: Tube DIY Asylum, RE: parallel feed (0.00)
Posted by gluca on 2011-05-03, 05:29:11 (192.88.212.44)
Has anyone built a single ended parallel feed amplifier? YES How does it sound. I can see the advantages, but are there any disadvantages with using a coupling cap? MAGNIFICENT (depends on irons, circ .......
152: MagneQuest/Peerless Forum, P+G, pinging MQ (0.00)
Posted by gluca on 2011-05-02, 15:41:54 (74.83.201.95)
Mike do you still have some P+G? 10k or 50k? I remember prices were over my budget for attenuators ... let me know Gianluca .......
153: High Efficiency Speaker Asylum, I paid recently ... (0.00)
Posted by gluca on 2011-05-02, 05:47:47 (192.88.212.34)
... 50$ apiece for 801As (NOS and tested) on epay. other tubes sell now for crazy prices but old RCA/WE compression drivers sell for even crazier prices. and what about some new HiFi gear out there so .......
154: High Efficiency Speaker Asylum, Thanks God they (0.00)
Posted by gluca on 2011-05-01, 20:27:24 (74.83.201.95)
usually do not mess with tubes. tubes, as a matter of facts, are a non-sense if you factor the economics in (but don't ask Gary Becker an opinion on the subject). me? I am a fool, I have boxes full of .......
155: Tube DIY Asylum, RE: Potenial dumb question....are the screens in the El34 run in pentode mode in the signal path? (0.00)
Posted by gluca on 2011-05-01, 17:27:08 (74.83.201.95)
would that make a difference? .......
156: High Efficiency Speaker Asylum, buahahhahhaha (0.00)
Posted by gluca on 2011-04-30, 17:50:48 (74.83.201.95)
oh yes, in the long run we are all dead. .......
157: Tube DIY Asylum, Nice build and ... (0.00)
Posted by gluca on 2011-04-28, 17:59:06 (74.83.201.95)
... and great trafos. Do you have now enough room for the DC filament supply? I'd suggest a Rod Coleman regulator being myself more than happy with them on my 211 and 801A. Gianluca .......
158: Tube DIY Asylum, what voltage? (0.00)
Posted by gluca on 2011-04-23, 22:48:25 (87.10.19.133)
thanks gianluca .......
159: Tube DIY Asylum, RE: This guy usually has them..... (0.00)
Posted by gluca on 2011-04-23, 12:35:12 (87.10.19.133)
hum ... shipping is quite expensive. they would work thou. .......
160: Tube DIY Asylum, source for 100uF motor run caps? (0.00)
Posted by gluca on 2011-04-23, 03:23:52 (87.10.19.133)
Hi I keep looking but I could not find any cheap source in USA for 100uF motor runs. A few made in China are on epay but I'd prefer other brands (ASC my favorite) Gianluca .......
161: High Efficiency Speaker Asylum, tried 2482? (0.00)
Posted by gluca on 2011-04-23, 02:29:39 (87.10.19.133)
Just curious. I no longer have the 41 but i strongly preferred 82 (mating JBL 2350). Actually I am concerned about tweeters with TADs (read below). .......
162: High Efficiency Speaker Asylum, RE: JBL 375 vs TAD 4001 vs Altec 288B (0.00)
Posted by gluca on 2011-04-21, 22:54:32 (87.10.19.133)
I had the altec 288 (then the JBL 2470) then the JBL 2441 then the JBL 2482 and now TAD 4001. They do go in my order of preference. Probably the altec is the only one I didn't really like due to the m .......
163: SET Asylum, jeff... (0.00)
Posted by gluca on 2011-04-20, 13:17:08 (87.10.19.133)
I would not call the 211 inferior. said that i'd look for a 801A amp. gianluca .......
164: MagneQuest/Peerless Forum, CCS (0.00)
Posted by gluca on 2011-04-19, 14:45:57 (87.10.19.133)
I have been using since ages cascoded depletion FETS by supertex or IXYS. Easy, cheap and darn good. Main advantage with CCSs is the superior power supply noise rejection and soundwise the music is mu .......
165: High Efficiency Speaker Asylum, more musings ... (0.00)
Posted by gluca on 2011-04-19, 14:22:01 (87.10.19.133)
hey, thanks all for the very very helpful replies. now i rewired the 2482 (coupled to the 300HZ Iwata) + 945N on one channel and the 4001 on the other side (no tweeter). the system is biamped with pre .......
166: High Efficiency Speaker Asylum, RE: The 4001 has too many anomalies in the highest frequencies (0.00)
Posted by gluca on 2011-04-18, 16:28:49 (87.28.88.109)
thanks everybody for the comments. I guess I was reading the very same comments on Romy's pages too back a few weeks ago. I was somehow convinced a two ways with 4001's covering all the mids and up to .......
167: High Efficiency Speaker Asylum, TAD 4001 & tweeters (0.00)
Posted by gluca on 2011-04-17, 12:08:45 (87.10.18.30)
How many of you are using a tweeter to complete the top end of your 4001? I switched two days ago from JBL 2350+2482 and fostex 945N to a TAD 4001 couplet to a 300Hz iwata horn (not the classic iwata .......
168: MagneQuest/Peerless Forum, beaddifful! (0.00)
Posted by gluca on 2011-04-17, 06:53:47 (87.10.18.30)
very nice build and excellent specs. i shielded B7's with mu-metal sheets and a mild iron can too. depending on your taste, I'd try a LED to bias the 417A and a CCS as load. gianluca .......
169: Tube DIY Asylum, RE: Whoa! (0.00)
Posted by gluca on 2011-04-04, 15:58:14 (208.102.122.162)
http://www.royaldevice.com/ .......
170: High Efficiency Speaker Asylum, RE: what are the realistic choices for a compression driver that can be crossed at 300hz or so. (0.00)
Posted by gluca on 2011-03-29, 14:00:05 (208.102.120.81)
you have PM on 2482s ... you might want to check Faitals .......
171: Tube DIY Asylum, RE: A popular DIY challenge noted (0.00)
Posted by gluca on 2011-03-17, 19:39:35 (208.102.120.81)
Q: What design are you thinking of building? A: A direct coupled PP into PP with CCS under the cathodes or a SE cap coupled to PP with CCS under the cathodes. 6CG7 as driver, VT52's at the output. Hig .......
172: Tube DIY Asylum, RE: motor run cap voltage (0.00)
Posted by gluca on 2011-03-15, 20:07:56 (208.102.120.81)
. .......
173: High Efficiency Speaker Asylum, RE: Replacement For JBL 2470 Phenolic Diaphragm (0.00)
Posted by gluca on 2011-03-13, 14:53:09 (208.102.120.81)
I liked and still like phenolic diaphragms. Be patient, maybe you'll fine done on epay. If going for aftermarkets check out radian. .......
174: Tube DIY Asylum, RE: Motor run DC rating (0.00)
Posted by gluca on 2011-03-08, 16:33:30 (208.102.120.81)
Reply I got directly from ASC tech support a couple years ago ... draw your conclusions from here or write the manufacturer (that would be the best answer you can have) "The 370V X386S can handle 600V .......
175: MagneQuest/Peerless Forum, RE: DPA 300B -- RIP Allen Wright (0.00)
Posted by gluca on 2011-03-01, 19:40:41 (208.102.120.81)
Very sad news ... these are actually days I am receiving bad news so often. I'll recycle the MQ-565 which is 7.1k plate-to-plate, MOL 17.5W . I bought them as I had a EL84 UL in mind but I could get m .......
176: Tube DIY Asylum, God Speed You Allen (0.00)
Posted by gluca on 2011-03-01, 16:27:06 (208.102.120.81)
So sad as only life can be sometime. You will be missed. .......
177: Tube DIY Asylum, maybe ... (0.00)
Posted by gluca on 2011-02-28, 06:44:24 (192.88.212.32)
Cathode resistor was, if memory serves me right, 470. I started with a bypassed cathode and it was horrible ... I believe that cap was in place for a couple hours only. Then unbypassed and finally bat .......
178: Tube DIY Asylum, RE: more ... (0.00)
Posted by gluca on 2011-02-28, 05:44:14 (192.88.212.32)
OH ... yes ... I had in mind (unbypassed) cathode bias. I use CCS as load and parafeed output transformer. .......
179: Tube DIY Asylum, more ... (0.00)
Posted by gluca on 2011-02-28, 05:09:59 (192.88.212.32)
What I found with my 801A preamp (now running 211s) is that fixed bias at the grid sounds better: I use a 9V battery and an input transformer. I am in the process of building a 801A spud amp and indee .......
180: Tube DIY Asylum, RE: Filament supply for 10, VT-25 preamp. (0.00)
Posted by gluca on 2011-02-27, 20:10:15 (208.102.120.81)
LCLCL filters or Rod Coleman's DC heater. .......
181: MagneQuest/Peerless Forum, RE: more ... (0.00)
Posted by gluca on 2011-02-26, 16:54:25 (208.102.120.81)
High PP load, indeed that is the plan. I'll make my ideas clearer in the next months. Thanks Keto. .......
182: MagneQuest/Peerless Forum, more ... (0.00)
Posted by gluca on 2011-02-24, 20:42:33 (208.102.120.81)
That looks really interesting but ... hum ... I made something similar with my headphone amp (single ended) and I found that a choke sounds better than a CCS in that spot. If you have a chance try it, .......
183: MagneQuest/Peerless Forum, do you ... (0.00)
Posted by gluca on 2011-02-24, 15:41:22 (192.88.212.44)
... have a schema to makes things easier to visualize for me? tks .......
184: MagneQuest/Peerless Forum, i know ... (0.00)
Posted by gluca on 2011-02-21, 17:57:02 (208.102.120.81)
it's me, I do not know what to do with parts lying around here and there ... .......
185: MagneQuest/Peerless Forum, Ping Keto (0.00)
Posted by gluca on 2011-02-20, 19:36:32 (208.102.120.81)
Keto, what happens at the start-up? And, have you ever tried a CCS under the 2A3s? I am gathering ideas for the next amp. Thanks Gianluca .......
186: MagneQuest/Peerless Forum, WHY!? (0.00)
Posted by gluca on 2011-02-20, 19:22:32 (208.102.120.81)
Why do we buy bunches of parts we never use ... ? My parts bin is full of 'I-don't-even-rememeber-why-I-bought-that-damn-part' parts. LOLz .......
187: MagneQuest/Peerless Forum, RE: Yes, but common mode chokes/mains filters (0.00)
Posted by gluca on 2011-02-19, 21:45:59 (208.102.120.81)
What is the lowest freq you need to filter out? And ... these (bigger) chokes probably have much higher shunt capacitance which makes them ineffective at higher freqs where smaller come into the game. .......
188: MagneQuest/Peerless Forum, RE: Crazy idea I know. ....but could the EXO-99 be used (0.00)
Posted by gluca on 2011-02-18, 17:06:36 (208.102.120.81)
Bas do you mean something like suggested by LL for their chokes (see the last connection diagram in the link)? Yes: 10mA (coils are in series) but common mode noise is rejected by a small amount due t .......
189: MagneQuest/Peerless Forum, RE: active loading with parallel feed? (0.00)
Posted by gluca on 2011-02-12, 22:31:43 (208.102.120.81)
Dan you want to use the parafeed calculator (mine or the more complete by voltsecond) to have an idea of what is going on with a CCS. Links to the spreadsheet have been posted here a number of times. .......
190: MagneQuest/Peerless Forum, Driver stage ... (0.00)
Posted by gluca on 2011-02-12, 15:47:34 (208.102.120.81)
I would use a gas regulator to bias the El84 as I did for my headphone/DAC PS. Mike thanks for the 565's ... so cute. Looking forward to make them sing. .......
191: SET Asylum, you can get rid of ... (0.00)
Posted by gluca on 2011-02-11, 20:32:31 (208.102.120.81)
... of the choke. for a low impedance output just connect the power tube grid to the upper mosfet source. that'is it. it will not drive the tube into A2 but will source some current if required ::: TO .......
192: MagneQuest/Peerless Forum, Ping MQ (0.00)
Posted by gluca on 2011-02-08, 16:10:27 (208.102.120.81)
Mike you got mail. Gianluca .......
193: MagneQuest/Peerless Forum, RE: here's teaser.... (0.00)
Posted by gluca on 2011-02-06, 13:02:16 (208.102.120.81)
Ni or Co .......
194: MagneQuest/Peerless Forum, mmmmhhhh (0.00)
Posted by gluca on 2011-02-06, 13:01:20 (208.102.120.81)
... I'll put on top of the buell a 3 seats sofa, a 24'' flat screen TV and some other stuff I have lying around here before I move. lolz seriously that is the best preamp output iron I have ever heard .......
195: MagneQuest/Peerless Forum, I am in. Ribs on! (0.00)
Posted by gluca on 2011-02-06, 11:32:05 (208.102.120.81)
Word. Confirmed. Write me down for a pair. Booked. Reserved. Mine! Mine! Mine! .......
196: MagneQuest/Peerless Forum, more ... (0.00)
Posted by gluca on 2011-02-06, 09:26:49 (208.102.120.81)
i rewired the little thing as a SRPP (output from the upper cathode) and probably with TL404 that is a good and wise choice: this is true with any other output transformer given the highish Rp of .......
197: MagneQuest/Peerless Forum, damn! i can't drink burbon ... (0.00)
Posted by gluca on 2011-02-06, 00:13:47 (208.102.120.81)
well... actually not even a beer. but that's it. yes, 6CG7 is much better and given the EX099's DCR it runs better and at higher current (10mA or so). 12BH7 and ECC99 were nowhere close to the optimum .......
198: MagneQuest/Peerless Forum, not a SRPP (0.00)
Posted by gluca on 2011-02-05, 16:45:15 (208.102.120.81)
... I'd call it choke assisted triode CCS ... or whatever. now running ECC99. meehehhe .......
199: MagneQuest/Peerless Forum, same but with 6CG7 (0.00)
Posted by gluca on 2011-02-05, 16:17:42 (208.102.120.81)
... it looks like I prefer 6CG7 to 12BH7 .......
200: MagneQuest/Peerless Forum, NO!? Not another line stage please! (0.00)
Posted by gluca on 2011-02-05, 14:28:01 (208.102.120.81)
It is just something I put together this afternoon. Not my usual piece of cake but I am liking it. PSU is a simple full wave 6X5GT into 0.1uF/10H/100uF and filament are running on AC. No hum in my hea .......
201: Tube DIY Asylum, your bias is out of control (0.00)
Posted by gluca on 2011-01-24, 15:57:20 (208.102.120.81)
ECC99 is biased at +1V ... that's why you are frying them. You have to drop that 108V at the grid or better increase the cathode voltage making R12 larger. EDIT: best thing you can do is use a CCS in .......
202: Tube DIY Asylum, J Swenson EL84 (0.00)
Posted by gluca on 2011-01-22, 16:56:50 (208.102.120.81)
Look for that design, he is running the screens higher that the plate in is EL84 amp. .......
203: Tube DIY Asylum, I trust ... (0.00)
Posted by gluca on 2011-01-12, 17:29:15 (74.83.60.173)
... I trust a pair of NOS sangano 2uF/2kV that have been running at 1.5kV for a couple years now. .......
204: Tube DIY Asylum, RE: or finding a parafeed capacitor you trust at 700V.... (0.00)
Posted by gluca on 2011-01-12, 11:29:09 (192.88.212.44)
see link .......
205: MagneQuest/Peerless Forum, hey! (0.00)
Posted by gluca on 2011-01-02, 14:16:19 (87.2.91.200)
we have 12 months in a year! more, we want more ;-) .......
206: Tube DIY Asylum, CCS (0.00)
Posted by gluca on 2010-11-30, 08:10:41 (192.88.212.32)
Votage amplifier: CCS loaded triode direcly coupled to the following stage or cap coupled (parafeed) to output transformer. I like CCS loaded SRPP as well and they work way better and cheaper than cho .......
207: SET Asylum, oh! (0.00)
Posted by gluca on 2010-11-15, 12:24:28 (192.88.212.34)
that would have been ominous indeed ... I stopped at 1.35kV with my 801A-75TL and I am kind scared. Not building any other high voltage amps any more, now I am relaxing with line driver, DAC, headphon .......
208: SET Asylum, RE: My take (on 6EW7) (0.00)
Posted by gluca on 2010-11-15, 11:34:19 (192.88.212.34)
Actually I am running B+ at 380V and voltage swing is good for my headphones and as line driver. Yes, you need more headroom as driver stage. I must admit I was surprised by this small tube, damn good .......
209: SET Asylum, My take (on 6EW7) (0.00)
Posted by gluca on 2010-11-15, 10:26:45 (192.88.212.34)
C1 is actaully smaller ... 4.7uF .......
210: MagneQuest/Peerless Forum, RE: Harman Kardon XT-3 DAC I/V (0.00)
Posted by gluca on 2010-11-14, 10:35:41 (72.49.174.110)
Chris I am (was actually as I am rebuilding the DAC) using the HK XT-3 with 4x PCM1704 (capable of 2.4mApp output each). 10ohm at the primaries and 50k at the secondary. The chart is the bandwidth of .......
211: SET Asylum, RE: 6H30 plate choke (0.00)
Posted by gluca on 2010-11-07, 19:04:28 (74.215.185.51)
100H is enough. 200H might be better. A CCS is best. .......
212: Tube DIY Asylum, Tks, btw ... (0.00)
Posted by gluca on 2010-10-20, 22:05:41 (72.49.172.161)
Thanks, I guessed below 0.1ohm too. Reason for asking is because Rod Coleman (over the DIYaudio forum) is testing a 75TL filament PSU of his own design, you might be interested (in case you didn't spo .......
213: Tube DIY Asylum, Question on 75TL/75TH (0.00)
Posted by gluca on 2010-10-20, 12:00:28 (192.88.212.43)
I am away from home (and I will be for a while) and I need to know the cold resistance of the 75's filament. Anyone out there can help? Thanks Gianluca .......
214: Tube DIY Asylum, OP for 211? (0.00)
Posted by gluca on 2010-10-15, 12:36:06 (192.88.212.34)
Are you using FS100PF? .......
215: Tube DIY Asylum, RE: 75TL (0.00)
Posted by gluca on 2010-10-15, 07:45:56 (192.88.212.34)
Let us know how it works, I'd go in A2 with such a load. I am not buying them for my 75TLs even if they seem OK ... I have only one spare 75TL left so I will convert the amp to use 211 one day. Thanks .......
216: Tube DIY Asylum, 75TL (0.00)
Posted by gluca on 2010-10-15, 07:13:31 (192.88.212.34)
Gapped for 70mA and 50:1 ratio ... that should be very OK for the 75TL, probably if it was a bit smaller would be even better: you will get only 5W out of the 75TL in A1. I still prefer parafeed thou. .......
217: Tube DIY Asylum, RE: Regulated Screens (0.00)
Posted by gluca on 2010-10-14, 13:13:12 (192.88.212.34)
I'll use regulated (shunt) screen supply in pentode modes. Follow the links I attach, that is the J Swenson's amp: he mentioned to me his project a while ago in an other discussion. That sounds intere .......
218: Tube DIY Asylum, RE: Damn! (0.00)
Posted by gluca on 2010-10-13, 13:28:06 (192.88.212.34)
I want to try all the solutions ... ah! if only I had the time. Looking forward to warm the solder iron up! .......
219: Tube DIY Asylum, Damn! (0.00)
Posted by gluca on 2010-10-13, 11:38:51 (192.88.212.34)
I forgot I need feedback... it sounds like I will replace that splitter for other duties (it has been hanging around for 3-4 years now). I do like actually the direct coupled amp by acrosound and .......
220: Tube DIY Asylum, Thanks (0.00)
Posted by gluca on 2010-10-13, 08:01:48 (192.88.212.34)
Thanks for all the hints and suggestions. First time working with EL84s and "small" tube power amps ... so basically I am both excited (sort of) and curious for this little puppy everybody says good t .......
221: Tube DIY Asylum, EL84 experts (0.00)
Posted by gluca on 2010-10-13, 04:42:02 (192.88.212.43)
Close to build a EL84 (push pull) amp but I have absolutely no experience with these tubes. Now I am collecting parts here and there, waiting on the OPTs etc... What about the many EL84 versions I see .......
222: SET Asylum, MI9355 uses 845's (0.00)
Posted by gluca on 2010-10-03, 06:28:20 (72.49.174.91)
and power tubes are biased individually while the 211's in the WE are sharing the cathode resistor. I'd love to have such a vintage amp ... .......
223: SET Asylum, RE: if PSE 211 is a "bad idea" how about PP 211? (0.00)
Posted by gluca on 2010-09-30, 19:24:41 (72.49.174.91)
The WE43A was a PP of 211's and used 211's as rectifiers too. If you have plenty of them ... .......
224: SET Asylum, RE: Parallel Single Ended 211 amp (0.00)
Posted by gluca on 2010-09-27, 16:14:25 (72.49.174.91)
meeehhh ... I would not use anything less than 10k for a single 211. That OPT should not be gapped so you need to parafeed it. .......
225: MagneQuest/Peerless Forum, RE: now? ready for the last jump in the big blue? (0.00)
Posted by gluca on 2010-09-27, 07:42:34 (192.88.212.44)
801 has a gain of 8x, but that should be ok. nice execution, i will never be able to build such a pro-looking chassis. one day my 75TL will die and I have only a spare left. I will rewire the amp to w .......
226: MagneQuest/Peerless Forum, now? ready for the last jump in the big blue? (0.00)
Posted by gluca on 2010-09-26, 14:00:20 (72.49.232.17)
get rid of the coupling cap and directly connect the plate of the 801A to the grid of the 845 (well ... a number of things must be changed before that!!!). you know what I mean. no turning back. OH! Y .......
227: MagneQuest/Peerless Forum, RE: 17173 Choke (0.00)
Posted by gluca on 2010-09-23, 09:04:06 (192.88.212.34)
indeed it is. i own a pair as well (nickel lams) .......
228: MagneQuest/Peerless Forum, Here it is (0.00)
Posted by gluca on 2010-09-22, 11:35:03 (192.88.212.34)
aaahhhh ... how many good ideas buried in this forum. it was not with 845 but with 811A, my memory failed as usual. .......
229: MagneQuest/Peerless Forum, RE: help me. i misplaced a schematic. exo173 (0.00)
Posted by gluca on 2010-09-22, 09:35:35 (192.88.212.34)
Hey Dan thanks. No it is not the PP i was looking for. What about the link? I cannot browse the whole database. Any homepage?? .......
230: MagneQuest/Peerless Forum, help me. i misplaced a schematic. exo173 (0.00)
Posted by gluca on 2010-09-22, 06:46:00 (192.88.212.32)
I remember there is an old (RCA? ALTEC?) amp using a choke splitter like the EXO-173 to drive a PP of 845. The choke is loading a cathode follower. I misplaced it and I'd love to retrieve it. Do you h .......
231: Tube DIY Asylum, RE: DC supplies for DHT's (0.00)
Posted by gluca on 2010-08-11, 10:43:42 (192.88.212.32)
umpf ... can you tie the two tubes at their cathodes? .......
232: MagneQuest/Peerless Forum, RE: input transformer for amplifier (0.00)
Posted by gluca on 2010-08-08, 10:45:53 (72.49.113.29)
Your preamplifier's tube will see a load that is the parallel of 1) the primary inductance of that output tranny 2) the reflected load which will be very high if you load with 500k the other input tra .......
233: MagneQuest/Peerless Forum, Take care Mike ... (0.00)
Posted by gluca on 2010-07-27, 19:34:36 (74.215.199.237)
... enjoy the good weather, the fresh fruits, the family, the friends, the cheesesteaks ... Thanks Kevin. Gianluca .......
234: MagneQuest/Peerless Forum, you forgot (0.00)
Posted by gluca on 2010-06-22, 12:53:32 (192.88.212.44)
point 1) ciao. .......
235: MagneQuest/Peerless Forum, I forgot (0.00)
Posted by gluca on 2010-06-20, 19:18:54 (72.49.247.36)
1) do use a 1.5k or greater resistor before the CCS, it will protect the FETs at the start-up. it is mandatory. 2) actually there is no need to drop 200V in the CCS (dissipating 4W), I believe 100V wo .......
236: K&K Audio / Lundahl Transformers, maybe ... (0.00)
Posted by gluca on 2010-06-04, 08:08:30 (192.88.212.44)
... but I like 801A so much. .......
237: K&K Audio / Lundahl Transformers, RE: GM70 PP (0.00)
Posted by gluca on 2010-06-02, 18:18:38 (72.49.247.36)
Ciao what driver? I liked (well ... that is no news) the 801A .......
238: Tube DIY Asylum, take care of the filaments. (0.00)
Posted by gluca on 2010-05-14, 08:04:03 (192.88.212.34)
enjoy it! gianluca .......
239: K&K Audio / Lundahl Transformers, that's a good results (0.00)
Posted by gluca on 2010-05-13, 16:27:12 (72.49.247.36)
I hope exotic cores will be available as well ... Me? I fell in love with nikels .......
240: K&K Audio / Lundahl Transformers, Thomas (0.00)
Posted by gluca on 2010-05-13, 07:38:00 (192.88.212.34)
Thanks for the good news. What about the low ends and primary L? Kevin, any forecasted date for its availability to the public? Gianluca .......
241: Tube DIY Asylum, finally! (0.00)
Posted by gluca on 2010-05-13, 06:51:38 (192.88.212.34)
been waiting for such a piece of iron .......
242: MagneQuest/Peerless Forum, RE: MQ-565 hookup information (0.00)
Posted by gluca on 2010-05-12, 20:11:01 (72.49.247.36)
Ciao Mike what about the pair I ordered a while ago? No hurry as I am still working on the dac, take your time, just curious. Gianluca .......
243: MagneQuest/Peerless Forum, maybe OT ... (0.00)
Posted by gluca on 2010-05-02, 15:03:44 (72.49.247.36)
... how boring is designing chassis with frontpanelexpress? Checking parts' dimensions, finding missing bits on digikey.com, taking note of everything... and find out you need to redraw it as there is .......
244: Tube DIY Asylum, Tube plate voltage is 175V ... (0.00)
Posted by gluca on 2010-04-27, 20:36:08 (72.49.247.36)
... that should suggest a rough number. BTW, I don't like high gain tube myself. Gianluca .......
245: K&K Audio / Lundahl Transformers, RE: I/V transformer for PCM1704 DAC once again... (0.00)
Posted by gluca on 2010-04-21, 01:11:46 (87.6.198.55)
I am pretty sure you will have no too-low-inductance problems with any of them .......
246: Tube DIY Asylum, RE: operating point for 801 driver (0.00)
Posted by gluca on 2010-04-18, 00:35:50 (87.6.198.55)
i liked it running as low as 300V/20mA .......
247: MagneQuest/Peerless Forum, AAAAAHHHHHHRRRGGG!!!!! (0.00)
Posted by gluca on 2010-04-17, 04:16:23 (87.11.14.6)
Stop it! you making me green of envy! Congrats! an other neat amp! Gianluca .......
248: MagneQuest/Peerless Forum, RE: parafeed triode connected C3m linestage (0.00)
Posted by gluca on 2010-03-24, 10:48:40 (192.88.212.43)
Ciao Sridhar that 3x rules is somehow applicable to power stage as a compromise between power and distortion but other (I cannot say minor) aspects factor in. More on this on the old, valuable and may .......
249: MagneQuest/Peerless Forum, good one! n/t (0.00)
Posted by gluca on 2010-03-17, 18:36:50 (72.49.255.247)
. .......
250: Computer Audio Asylum, interesting ... (0.00)
Posted by gluca on 2010-03-14, 09:32:00 (72.49.248.221)
I'll try ... I was about to buy a new HD for backup. I'll get myself a firewire. I am using HiFace on MAC powerbook running OSX 4.11 latest iTunes and an external USB HD and it pops and clicks too. I .......
251: Computer Audio Asylum, it worked. thanks n/t (0.00)
Posted by gluca on 2010-03-13, 20:55:39 (72.49.248.221)
. .......
252: Computer Audio Asylum, real DVD audio (0.00)
Posted by gluca on 2010-03-13, 10:06:29 (72.49.248.221)
I can dwload it on my botebook I use at work. Thanks. .......
253: Computer Audio Asylum, any good way to extract audio (0.00)
Posted by gluca on 2010-03-12, 08:27:18 (192.88.212.34)
tracks for an audio DVD on a MAC? I am using soundflowerbed + audacity but it is not that comfortable thanks. .......
254: MagneQuest/Peerless Forum, russian caps codes (0.00)
Posted by gluca on 2010-03-07, 20:46:52 (208.102.212.232)
copied and saved long time ago from somewhere. i do use FT3 and KBG, but i found i like films more that papers. never tried k75. if any of you would post impressions here, that would be helpful for ev .......
255: MagneQuest/Peerless Forum, I have them (0.00)
Posted by gluca on 2010-03-07, 17:19:57 (208.102.212.232)
agreed, great sound and really cheap. but I am more oriented towards a different sound. .......
256: Tube DIY Asylum, aaaaaaahhhh ... finally ;-) nt (0.00)
Posted by gluca on 2010-03-07, 11:42:07 (208.102.212.232)
. .......
257: MagneQuest/Peerless Forum, I'll try (0.00)
Posted by gluca on 2010-03-04, 12:38:21 (192.88.212.34)
I used many times CCS's but never explored the phenomenon. Thanks .......
258: MagneQuest/Peerless Forum, that gives roughly (0.00)
Posted by gluca on 2010-03-04, 11:24:58 (192.88.212.34)
0.1W at the output which is the max for the headphones. but it is something very easy to try. .......
259: MagneQuest/Peerless Forum, yes. that one. (0.00)
Posted by gluca on 2010-03-04, 07:00:11 (192.88.212.34)
4.7uF to 10uF should work. ASC? source for them? .......
260: MagneQuest/Peerless Forum, muahahhaahah!! (0.00)
Posted by gluca on 2010-03-04, 05:27:33 (192.88.212.34)
now I need a coupling cap. it seems I like obbligatos better than solens. must try something else. .......
261: MagneQuest/Peerless Forum, Would someone please stop that guy??? (0.00)
Posted by gluca on 2010-03-03, 15:37:14 (72.49.122.84)
How ugly is the TL404? :-) Me got very last pair, me happy. More comments later, me is in a hurry ... me going dinner friends place. Me says it sounds very good. .......
262: Tube DIY Asylum, discontinued? they have cornell dubilier (0.00)
Posted by gluca on 2010-02-26, 10:47:07 (192.88.212.43)
http://it.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=2508309241 .......
263: Tube DIY Asylum, RS-Components carry them ... (0.00)
Posted by gluca on 2010-02-25, 07:08:58 (192.88.212.43)
... well, that's in Italy and are offered as "extended catalog" gianluca .......
264: MagneQuest/Peerless Forum, Me too... (0.00)
Posted by gluca on 2010-02-23, 20:40:56 (74.215.207.237)
Mah? I'll try again swapping the channels. But tonight the amp was lunatic, sometime it happens. So I went out, popped in a bar for live jazz music. Guitar, drum, double bass and sax on the stage; 9 p .......
265: MagneQuest/Peerless Forum, done (0.00)
Posted by gluca on 2010-02-23, 14:47:04 (74.215.207.237)
well I can't say anything about the swapping as differences are maybe subtle: I should modify the left channel and listen to the two version at same time but left has no dropping resistor (tube parame .......
266: MagneQuest/Peerless Forum, will do tonight ... (0.00)
Posted by gluca on 2010-02-23, 04:59:23 (192.88.212.44)
I think I heard that trick a while ago, probably it was you. .......
267: Tube DIY Asylum, thanks! (0.00)
Posted by gluca on 2010-02-22, 17:30:11 (74.215.207.237)
Those are more pricey than tubedepot's but have a great vintage look. I am not restoring a pultec but I decided to give my preamp a pultec look ... which I find to be so coool Gianluca .......
268: Tube DIY Asylum, found on tubedepot n/t (0.00)
Posted by gluca on 2010-02-22, 16:58:16 (74.215.207.237)
. .......
269: Tube DIY Asylum, pultecs controls (0.00)
Posted by gluca on 2010-02-22, 15:54:22 (74.215.207.237)
do you know where I can find old style knobs and chicken heads .......
270: MagneQuest/Peerless Forum, HEY! I said QUIT WITH THIS HEADPHONE AMP POSTING! (0.00)
Posted by gluca on 2010-02-21, 14:48:36 (74.215.207.237)
OH! My God ... would you please ... you are abusing of my patience, just stop it. OK? A LED, it sounds a bit better. What MK is this? 6?? .......
271: MagneQuest/Peerless Forum, you have mail n/t (0.00)
Posted by gluca on 2010-02-20, 00:01:59 (74.215.207.237)
. .......
272: MagneQuest/Peerless Forum, MQ-565 (0.00)
Posted by gluca on 2010-02-19, 13:56:31 (192.88.212.43)
More on those OPTs? The idea is to build a EL84 ultralinear amp. I'd love to play with that compact amp idea or to use my EXO173PPS. Let me know ... G .......
273: MagneQuest/Peerless Forum, so it has UL taps! (0.00)
Posted by gluca on 2010-02-19, 11:51:45 (192.88.212.43)
I'd put dibs on them ... I'd love to build a cheap EL84s PP amp. Pending a price within my budgets and more info on that lams thing. how big are they? open frame or bell ends? PM me for details. Gianl .......
274: MagneQuest/Peerless Forum, zebrawood maybe? (0.00)
Posted by gluca on 2010-02-18, 21:16:16 (74.215.207.237)
I remember a very nice chassis in zebrawood by docB but I could ntot find any pic. I am not even close to think of being a decent woodworker ... I'd need someone to build it for me. For the time being .......
275: MagneQuest/Peerless Forum, umpf ... quite expensive (0.00)
Posted by gluca on 2010-02-18, 19:55:23 (74.215.207.237)
... nice job. i am under the impression that this small DAC/preamp is going to cost me quite a lot. .......
276: MagneQuest/Peerless Forum, RE: again? cut it dude ... (headphone amp) (0.00)
Posted by gluca on 2010-02-17, 20:21:36 (74.215.202.227)
your preamp is something i was looking at for inspiration. .......
277: MagneQuest/Peerless Forum, I'd like a TL-404 with some cool core (0.00)
Posted by gluca on 2010-02-17, 20:03:05 (74.215.202.227)
Q1 is fine, voltage drop is not that high and heat is handled by a heatsink... nice trick btw. .......
278: MagneQuest/Peerless Forum, again? cut it dude ... (headphone amp) (0.00)
Posted by gluca on 2010-02-17, 16:47:00 (74.215.202.227)
OK, I made it. I rewired the amp, refer to my old post for comments. I added a few measurements I took to help in case you are going to build it. I am running it hotter (increased the bias currents) h .......
279: Tube DIY Asylum, nope. (0.00)
Posted by gluca on 2010-02-17, 12:36:41 (192.88.212.32)
I got exactly what I need with the FS's .......
280: Tube DIY Asylum, gap (0.00)
Posted by gluca on 2010-02-16, 20:35:54 (72.49.125.79)
Mine had E's and I's stacked butt to butt but no paper in between. I had to open the bells and put some post-its in between, no big deal ... a few trials and errors and you find the best gap size. Wha .......
281: Tube DIY Asylum, FS100-PF by MQ n/t (0.00)
Posted by gluca on 2010-02-16, 20:28:08 (72.49.125.79)
. .......
282: Tube DIY Asylum, Me (0.00)
Posted by gluca on 2010-02-16, 15:10:48 (72.49.125.79)
... they were ungapped (!), unsure about the voltage insulation, really small. sold them right after the prototype amp was running. .......
283: MagneQuest/Peerless Forum, 801A 20mA/300V (0.00)
Posted by gluca on 2010-02-15, 18:17:27 (72.49.125.79)
you will miss the gain tho ... that's how I was running mine before switching to SE .......
284: Tube DIY Asylum, umpf ... (0.00)
Posted by gluca on 2010-02-13, 19:39:40 (72.49.125.79)
go get same 801Y .......
285: Tube DIY Asylum, RE: not for the faint of heart....... (0.00)
Posted by gluca on 2010-02-12, 20:29:44 (72.49.125.79)
Whatever your choice is, I'd stay with a 10k OPT. What driver are you using? .......
286: MagneQuest/Peerless Forum, missing schematic (0.00)
Posted by gluca on 2010-02-10, 15:26:22 (72.49.125.79)
dunno, it was there (I think) .......
287: MagneQuest/Peerless Forum, kudos! (0.00)
Posted by gluca on 2010-02-09, 18:25:11 (74.215.201.143)
neat, very nice. those v-caps ... yummy .......
288: MagneQuest/Peerless Forum, RE: preamp/headphone MKIV (0.00)
Posted by gluca on 2010-02-06, 21:46:26 (72.49.240.116)
well... power supplies will need a pair of irons for sure :-) .......
289: MagneQuest/Peerless Forum, preamp/headphone MKIV (0.00)
Posted by gluca on 2010-02-06, 14:24:07 (72.49.240.116)
I didn't build it, I am not going to build it ... more on this at the end of the message. The ideas behind this preamp and headphone amp are: 1) direct coupling of the stages 2) excellent driving capa .......
290: MagneQuest/Peerless Forum, RE: Bas, here it is the headphone amp mk3 (0.00)
Posted by gluca on 2010-02-05, 11:19:40 (192.88.212.44)
John not that much actually, tubes stay pretty much at the same bias after hours of use. At the start-up current in the higher tube goes up and reaches the stabilized value after a few seconds. You go .......
291: MagneQuest/Peerless Forum, RE: Don't think I've ever seen something like that... (0.00)
Posted by gluca on 2010-02-05, 04:49:02 (192.88.212.44)
Ciao Bas, the CCS is passing 6mA (7mA in the other channel) but you need to adjust it and R2 to dial in the higher tube at 20mA (or whatever current you want it to run at). B+ is 310V but I need to ch .......
292: MagneQuest/Peerless Forum, Bas, here it is the headphone amp mk3 (0.00)
Posted by gluca on 2010-02-04, 20:57:42 (72.49.240.116)
No smoke for the time being, brubeck hits the keys just in my ears. OH! Gianluca .......
293: Computer Audio Asylum, Extracting audio from dvd's on mac (0.00)
Posted by gluca on 2010-02-04, 19:24:30 (72.49.240.116)
Ciao I am using soundflowerbed -> audacity to extract 24/96 audio file encoded into a DVD's files (Red by King Crimson recently released in HiRes). First time I do that, any experience or comment from .......
294: MagneQuest/Peerless Forum, RE: custom iron for GL (0.00)
Posted by gluca on 2010-02-04, 05:25:14 (192.88.212.34)
Ciao Mike, thanks for running the numbers. The 75TL Rp is in the 6k ballpark and I would like to load it with a 24k:16/8 that is a 40:1 step-down ratio from plate to voice coil. One single secondary a .......
295: MagneQuest/Peerless Forum, RE: inquiry about PCM1798 DAC (0.00)
Posted by gluca on 2010-02-02, 19:56:37 (72.49.240.116)
I am converting Iout from 4x PCM1704 to V using 22+22ohm and HK XT3. Mic inputs or step-ups might work (1798 has balanced outputs, worth looking for two primaries). .......
296: MagneQuest/Peerless Forum, Yes reading ... more. (0.00)
Posted by gluca on 2010-02-02, 14:17:49 (192.88.212.32)
... my parafeed calculator is stored on Dave Slagles forum. For my 304TL amp I used the FS100PF and its mating choke (gapped for 100mA). Jeff is aiming for higher voltages on the plate and lower loads .......
297: MagneQuest/Peerless Forum, no, it will be mk3 (0.00)
Posted by gluca on 2010-02-02, 05:44:14 (192.88.212.32)
but I am currently working with *cough* *cough* opamp *cough* ... ooops ... did I say opamps? me, I am sorry. .......
298: MagneQuest/Peerless Forum, thanks ... (0.00)
Posted by gluca on 2010-01-30, 22:15:11 (72.49.240.116)
... if the whole thing doesn't explode I'll you show you the next mod. gianluca .......
299: MagneQuest/Peerless Forum, mk2.1 ... n/t (0.00)
Posted by gluca on 2010-01-30, 16:12:55 (72.49.240.116)
. .......
300: Tube DIY Asylum, wait one more minute (0.00)
Posted by gluca on 2010-01-29, 23:14:22 (72.49.240.116)
... do not forget the L of the transformer ... .......
301: MagneQuest/Peerless Forum, A headphone amp. mk2 (0.00)
Posted by gluca on 2010-01-28, 16:23:36 (72.49.240.116)
Here we are. What's better now? Everything seems to be more clear: speech, drums, trumpets, high freqs makes the sound sharper. Gain (I mean SPL has I have no o/scope to measure it) increased a bit as .......
302: Tube DIY Asylum, Sure ... (0.00)
Posted by gluca on 2010-01-28, 12:31:47 (192.88.212.44)
... but I'd prefer to suspend the socket on the standoffs (possibly made of rubber to provide the system with some isolation from vibrations)inside the amp. I know ... a drawing would help in making m .......
303: MagneQuest/Peerless Forum, RE: A headphones amp. (0.00)
Posted by gluca on 2010-01-28, 09:09:30 (192.88.212.44)
You need to tweak a bit the resistors to find the balance but I didn't experience any runaway or major instabilities. .......
304: MagneQuest/Peerless Forum, I do not ... (0.00)
Posted by gluca on 2010-01-28, 09:07:21 (192.88.212.44)
... not even thinking to opamps. doh?! ;-) I saw out there many "audiophile approved" and "correspondingly highly priced" headphones amps are available to those many people. .......
305: Tube DIY Asylum, Thanks (0.00)
Posted by gluca on 2010-01-28, 06:28:08 (192.88.212.44)
Reasons for searching those sockets is that I want to mount them using standoffs inside the amp. .......
306: Tube DIY Asylum, sockets (0.00)
Posted by gluca on 2010-01-27, 19:32:24 (72.49.240.116)
do you guys know if there are sockets like the AN (octal and noval) that do NOT need any ring to be mounted onto the chassis?? something with a more affordable price. thanks gianluca .......
307: MagneQuest/Peerless Forum, RE: A headphones amp. (0.00)
Posted by gluca on 2010-01-27, 18:25:34 (72.49.240.116)
Hank, i noted your pre a while ago. How do you like 6C45pi? .......
308: MagneQuest/Peerless Forum, RE: let's assemble a list of 500/600 ohm earphones.... (0.00)
Posted by gluca on 2010-01-27, 18:24:17 (72.49.240.116)
Mike beyerdynamic T1 (but you don't want to ask the price) beyerdynamic DT990 (600ohm voice coil version not listed any more) beyerdynamic DT880 (600ohm voice coil version not listed any more) you can .......
309: MagneQuest/Peerless Forum, More (0.00)
Posted by gluca on 2010-01-27, 17:50:02 (72.49.240.116)
Mike I got my DT990 from that very seller. I managed to get a slightly better price, not cheap but I am liking them. 600ohm headphones seem to be the proper choice to me has I design my preamps with a .......
310: Tube DIY Asylum, 83, 'cause it's so cute ... (0.00)
Posted by gluca on 2010-01-26, 20:33:12 (72.49.240.116)
... never had noise problems with Hg rectfiers. They need extra care/time at the start up and sometime they just do not ignite (when dead) but I cannot do without. All the posts below tell more. ::: T .......
311: MagneQuest/Peerless Forum, A headphones amp. (0.00)
Posted by gluca on 2010-01-26, 18:02:24 (72.49.240.116)
Ciao I am not used to those little puppies but ... here it is. This is the first and basic version of my new (actually first) headphones amp. A handful of parts and two tubes. I posted the idea a whil .......
312: Tube DIY Asylum, voltage divider (0.00)
Posted by gluca on 2010-01-18, 18:03:56 (72.49.240.116)
just use two big resistors hooked up in series to your hi voltage and take the measures in the middle. cheap and safe ... well a 1kV amp is not, strictly speaking, "safe". Be always more than cautious .......
313: MagneQuest/Peerless Forum, RE: OPT Primary impedance Q. (0.00)
Posted by gluca on 2010-01-16, 21:41:55 (72.49.240.116)
Hum ... you can try but most probably you will not have enough Henrys. I would not make a transformer with much more L than required: bigger L calls in for bigger core and more turns which means lower .......
314: Tube DIY Asylum, 6.3V rectifiers suggestion (0.00)
Posted by gluca on 2010-01-15, 17:05:03 (72.49.240.116)
Ciao, I am not familiar with 6.3V filament rectifers so would you please point me to a right choice? It will be for a 300VDC/50mA duties as a maximum. You can make it 200V/30mA for the DAC. Supplies w .......
315: MagneQuest/Peerless Forum, RE: OPT Primary impedance Q. (0.00)
Posted by gluca on 2010-01-15, 05:04:52 (192.88.212.32)
If I got your Q properly ... you would double the reflected speaker impedance from the secondary but the primary L would be the same and maybe not great enough to balance the reflected 10K. That is, i .......
316: Tube DIY Asylum, RE: Using the Screen as Anode (0.00)
Posted by gluca on 2010-01-02, 09:54:41 (87.11.254.13)
I looked again and it was probably removed. It was posted by screenmode over the oswaldmills forum a while ago (1 year or so). They are offering now an amp based based on that very idea. http://www.os .......
317: Tube DIY Asylum, RE: Using the Screen as Anode (0.00)
Posted by gluca on 2010-01-02, 09:28:56 (87.11.254.13)
I've seen a schematic with EL519 pr PL519 using screen as anode and it was reported it was a great sounding amp. I misplaced the schematic unfortunately gianluca .......
318: MagneQuest/Peerless Forum, RE: My new project. And thanks to Mike and Keto! (0.00)
Posted by gluca on 2010-01-01, 08:57:53 (82.59.226.100)
Where did you find the TL404? Old stock or by Mike MQ? .......
319: Tube DIY Asylum, thanks Ed (0.00)
Posted by gluca on 2009-12-29, 00:17:47 (87.16.249.161)
I installed two new (no birdcage) tubes and everything is fine. Thats it, the tube is dead and the others lost the vacuum. I'll shoot you a mail when back in the USA (jan 10th). Let me know if you nee .......
320: Tube DIY Asylum, so it's dead (0.00)
Posted by gluca on 2009-12-28, 13:24:58 (87.16.249.161)
sob. thanks for the replies. those very my last birdcages, i have two more but they do not have the punched plate gluca .......
321: Tube DIY Asylum, RE: Help on some 394A thyratrons and MV rectifers (0.00)
Posted by gluca on 2009-12-28, 13:01:21 (87.16.249.161)
Ciao, mmmhhh, that cannot be. Filaments are in series and one is up. .......
322: Tube DIY Asylum, Help on some 394A thyratrons and MV rectifers (0.00)
Posted by gluca on 2009-12-28, 11:16:33 (87.16.249.161)
Ciao I have been using 394As (grid as plate) for quite a while in my line driver (I'd say couple of years) and all of a sudden one tube turned dark blue. It usually is light blue. The bridge went nuts .......
323: MagneQuest/Peerless Forum, Cincinnati ... (0.00)
Posted by gluca on 2009-12-28, 11:09:07 (87.16.249.161)
... hey thanks for the puppies. I'll use the EX099 to load my 75TH in a new low gain line driver, I will dismantle the 211 based preamp during the next year/summer. ... Cincinnati. Well, it's OK but I .......
324: Tube DIY Asylum, Thomas (0.00)
Posted by gluca on 2009-12-28, 03:07:43 (87.10.251.160)
More about filaments. I tried quite a number of ideas including 3pins regulators and SS. At the end I settled to LLCLLCL (LL is a two bobbins choke a la Lundahl) which is dead quite and it is not wast .......
325: MagneQuest/Peerless Forum, Hold on! I'll be back late in january (0.00)
Posted by gluca on 2009-12-27, 12:21:50 (87.10.251.154)
So please wait 10 days before shipping. Send me the balance due, paypal ready, shipping address will be in the payment mail. Gianluca .......
326: Tube DIY Asylum, RE: When stacking power supplies.... (0.00)
Posted by gluca on 2009-12-27, 00:49:11 (82.59.226.221)
If I were to use different rectifiers I'd use the slower one on the higher PSU (I turn low voltage PSU on first and after a few seconds the high voltage) Gianluca .......
327: Tube DIY Asylum, RE: 304TL curves. (0.00)
Posted by gluca on 2009-12-27, 00:46:13 (82.59.226.221)
OH! If only I had those a couple of years ago. Btw thanks, I much appreciated the 75TL curves as well. Gianluca .......
328: MagneQuest/Peerless Forum, 20B ... good choice ... (0.00)
Posted by gluca on 2009-12-25, 16:42:34 (87.11.254.100)
... maybe expensive, but good. .......
329: MagneQuest/Peerless Forum, here (0.00)
Posted by gluca on 2009-12-25, 16:40:46 (87.11.254.100)
hey! thanks for the replies. here it is my mail address gl(dot)sperti(@)libero(dot)it don, let me know. ciao gianluca .......
330: MagneQuest/Peerless Forum, More on HK XT-3 (HEY! Merry Xmas!!!) (0.00)
Posted by gluca on 2009-12-25, 03:47:22 (87.7.93.178)
merry xmas to all of you! I hooked up the XT3 to the oscilloscope and fx generator ... that's eggsactly what I was looking for, nice puppy. -0.5db at 20Hz and 20kHz and a nice fall at higher freqs. Rs .......
331: Tube DIY Asylum, answers (0.00)
Posted by gluca on 2009-12-20, 15:46:45 (72.49.116.242)
Q: Would a grid choke work well instead of the 22K leak infront of the 801a? A: Yes. Please not that I am using an input transformer, the grid choke would offer more L but going from 400H to 4000H (or .......
332: Tube DIY Asylum, gotcha (0.00)
Posted by gluca on 2009-12-20, 14:54:06 (72.49.116.242)
The schematic is that one. The problem I had was with the choke: I brutally abused its mA rating (gapped for 20mA and I was running 30mA or so). You need to play with Rx do find the best bias for the .......
333: Tube DIY Asylum, 801A (0.00)
Posted by gluca on 2009-12-20, 14:22:14 (72.49.116.242)
I agree with Jim Dowdy about thoriated triodes. I found a great combo using the 801A, I love the result. I used 801A with 304TL and 75TL now. Give the 801A a try as driver. Gianluca .......
334: MagneQuest/Peerless Forum, RE: Come enjoy MQ's magic winterland! (0.00)
Posted by gluca on 2009-12-20, 14:16:39 (72.49.116.242)
I saw it on TV yesterday night. Here in cincinnati is snowing but it melts as it touches the pavement, I'd say it's raining now. Cold in the 30F. Is your buell well garaged? .......
335: MagneQuest/Peerless Forum, RE: Heavy metal, too much of a good thing? (0.00)
Posted by gluca on 2009-12-14, 07:37:35 (192.88.212.32)
I have a EXO173 with Ni lams. Go for it. Period. .......
336: MagneQuest/Peerless Forum, sure thing (0.00)
Posted by gluca on 2009-12-04, 05:54:53 (192.88.212.44)
I will do. as a matter of facts I did it in every parafeed amp I built. .......
337: MagneQuest/Peerless Forum, Thanks (0.00)
Posted by gluca on 2009-12-04, 05:53:53 (192.88.212.44)
Gordon I do have a sabre and I like it (it is the buffalo dac) running into a jensen 600:600 transfomer. Plain vanilla. The dac will have 4 BB1704 per channel so drive capability is a bit higher. I'll .......
338: MagneQuest/Peerless Forum, This is the idea ... (0.00)
Posted by gluca on 2009-12-03, 19:50:06 (74.215.198.154)
... I am working on. NOT TESTED! I am posting it to have it commented by you folks. DAC is based on a multiple BB1704. IV is a passive resistor A low order filter and the step-up (the Harmon Kardon TX .......
339: MagneQuest/Peerless Forum, GOT THEM - THANKS - (0.00)
Posted by gluca on 2009-12-03, 16:19:02 (74.215.198.154)
but all this was useless ... the poor puppy has been killed by a violent killer. good stuff, looking forward to finish with my project to listen to the lil trannies. gianluca .......
340: MagneQuest/Peerless Forum, OK (0.00)
Posted by gluca on 2009-12-02, 06:39:32 (192.88.212.44)
I'll pay her to go get you. Scared now? .......
341: MagneQuest/Peerless Forum, OH! OH! The big brother is looking for you ... (0.00)
Posted by gluca on 2009-12-01, 18:54:46 (72.49.116.221)
. .......
342: MagneQuest/Peerless Forum, RE: B7 and 12b4 parafeed cap size (0.00)
Posted by gluca on 2009-12-01, 06:03:55 (192.88.212.44)
yes, make it big. .......
343: MagneQuest/Peerless Forum, RE: B7 and 12b4 parafeed cap size (0.00)
Posted by gluca on 2009-11-30, 13:09:05 (192.88.212.43)
Download here my old xls file http://www.intactaudio.com/forum/viewtopic.php?t=316 I do not have the voltseconds site handy but he made a great calculator for parafeed stages. Google it. Gianluca ::: .......
344: SET Asylum, RE: 845 based SET monoblocks (0.00)
Posted by gluca on 2009-11-29, 17:33:49 (12.185.225.30)
consider gm70 and triode strapped 813 for cheaper *much cheaper* options with great balance, tone and power. Those tubes are really impressive too. .......
345: MagneQuest/Peerless Forum, more *save the puppy* (0.00)
Posted by gluca on 2009-11-29, 17:21:28 (12.185.225.30)
the idea is to use the tranny as an i/v converter in conjunction with a low value resistor and filter at the primary and a 50k pot at the secondary. A tube voltage gain stage and the beeseven 10k will .......
346: MagneQuest/Peerless Forum, in for a pair (0.00)
Posted by gluca on 2009-11-28, 16:42:22 (87.10.250.229)
payment pending 'till next monday as I will be travelling tomorrow. use? in my dac. thanks gianluca .......
347: MagneQuest/Peerless Forum, good stuff (0.00)
Posted by gluca on 2009-11-25, 15:15:57 (87.7.95.88)
damn good stuff. the best input tranny i ever used so far. use extra care to avoid picking-up noise so keep the psu away from it. .......
348: SET Asylum, I do not agree (0.00)
Posted by gluca on 2009-11-22, 10:37:03 (82.59.228.68)
You can tune the square wave response of a tube+IT with a zobel to have a nice looking oscilloscope measurement but that will not say much about the taste of the amp. Me? I never built a 300B (just a .......
349: Tube DIY Asylum, no (0.00)
Posted by gluca on 2009-11-07, 13:14:59 (72.49.119.235)
I always have the cathode at ground and bias the grid negative by the batteries (via the secondary coils of the input transformer). I do prefer going this way. gianluca .......
350: Tube DIY Asylum, RE: Battery Bias; Are you using it? Why or Why not? (0.00)
Posted by gluca on 2009-11-06, 21:18:10 (72.49.119.235)
Do you mean you want to bias the tube at the grid (1) or with a battery at the cathode (2)? (1) it would last many many months ... I check them every 6 months and they are OK. The voltage fades away s .......
351: SET Asylum, RE: I shall be lanced for this... (0.00)
Posted by gluca on 2009-11-05, 16:27:01 (72.49.119.235)
my preferred tube, well my 2nd preferred tube ... 75TL comes first. .......
352: MagneQuest/Peerless Forum, thumbs up (0.00)
Posted by gluca on 2009-11-04, 19:29:34 (72.49.244.14)
great job! .......
353: MagneQuest/Peerless Forum, RE: Follow-Up (0.00)
Posted by gluca on 2009-10-26, 12:53:58 (192.88.212.32)
You really need a cap at the OPT center tap as discussed a few days ago. Keep us posted, interesting subject. Gianluca .......
354: MagneQuest/Peerless Forum, RE: Follow-Up (0.00)
Posted by gluca on 2009-10-25, 18:17:40 (72.49.242.58)
Not sure I got your idea properly. What did you lift? .......
355: MagneQuest/Peerless Forum, How do you like it? (0.00)
Posted by gluca on 2009-10-20, 21:02:57 (72.49.242.58)
I mean... I used 6C45pi and I found it a bit dry if such a word makes sense in audio. OH?! Yes, me too, I will be using beeseven. Neat building, kudos! Gianluca .......
356: MagneQuest/Peerless Forum, DC problem (0.00)
Posted by gluca on 2009-10-08, 12:28:38 (192.88.212.43)
I mean, in the schematic posted above the coil of the OPT will be tied at 300V at one end and ground at the other so a net current will flow which is 300V/whatever_the_DCR_of_the_coil_is. In the serie .......
357: MagneQuest/Peerless Forum, more (0.00)
Posted by gluca on 2009-10-08, 12:20:08 (192.88.212.43)
@ John Yes the -45V (that is 5*9, I mean do use 5 batteries to make it simple and dirt) goes to the PPS center tap. I used the EXO173 that way a number of times. And you will have no way to balance th .......
358: MagneQuest/Peerless Forum, It would work. Schematic updated. (0.00)
Posted by gluca on 2009-10-08, 11:27:08 (192.88.212.43)
Thanks for the hints on 6EW7, I'll have 400V B+ so there will be room for a DC coupled stage. PS B) doesn't make that much sense to me. EDIT: I would make it even simpler. Get rid of the CCS under the .......
359: MagneQuest/Peerless Forum, RE: Missing parafeed caps in the schems (0.00)
Posted by gluca on 2009-10-08, 10:10:52 (192.88.212.43)
>Unless I'm mistaken (50-50 chance, I suppose), getting rid of the >parafeed caps is the whole point of ensuring that both tubes draw the >same DC current (in this case, 60mA for the 2A3s), so they ar .......
360: MagneQuest/Peerless Forum, Missing parafeed caps in the schems (0.00)
Posted by gluca on 2009-10-08, 08:20:52 (192.88.212.43)
I'd stick with a series feed transformer in your PP amp: the LCL combo at the output is anyway a resonant cell (that follows the LCL before the 2A3s) which introduces further phase shifts and blah bla .......
361: MagneQuest/Peerless Forum, CCS on tails (0.00)
Posted by gluca on 2009-10-07, 21:03:31 (208.102.213.107)
Well ... actually with just one CCS under the 2A3s tails you cannot adjust for any DC imbalance. But if you tie the 2A3s cathodes and use a CCS to bias the pair you get a differential amp that should .......
362: MagneQuest/Peerless Forum, guitar/bass amp (0.00)
Posted by gluca on 2009-09-13, 21:25:50 (72.49.251.233)
LOL ... .......
363: MagneQuest/Peerless Forum, BAAAAAS!! (0.00)
Posted by gluca on 2009-09-04, 13:26:33 (74.215.200.33)
>I have many other things that keep me busy those words lead me to argue you are not using the 2 copper GM70s I sent you ... do you plan to use FS100 with those puppies?? I used FS-100-PF. A great com .......
364: MagneQuest/Peerless Forum, pong (0.00)
Posted by gluca on 2009-08-26, 20:36:25 (74.215.201.71)
I had two cheese steaks: one at Geno's and one at Pat's. I liked Pat's most. Funny how they grew up one in front of the other and both of them are really crowded. More pics here http://www.flickr.com/ .......
365: MagneQuest/Peerless Forum, muhahaaaaha (0.00)
Posted by gluca on 2009-08-25, 17:09:03 (72.49.250.122)
we need a couple of sexy girls and the pic will be perfect :-) g .......
366: MagneQuest/Peerless Forum, Ping MQ (pics) (0.00)
Posted by gluca on 2009-08-24, 21:24:34 (72.49.250.122)
Ciao Mike I left a voice message on your number but we could not meet. OH! I was looking forward to shake your hand and have a beer. Next time. Philly, I have been there just one night and left the .......
367: MagneQuest/Peerless Forum, I LOVE IT (0.00)
Posted by gluca on 2009-08-04, 12:42:12 (192.88.212.44)
Thats a GORGEOUS cafe racer, I am sure you like the current Ducati Sport classic. CONGRATULATIONS!!! Gianluca .......
368: MagneQuest/Peerless Forum, That makes perfectly sense to me (0.00)
Posted by gluca on 2009-08-03, 18:47:39 (72.49.247.146)
Sometime I turn my amplifiers and part of them into smoke as well. I cannot say I consider myself happy when that happens which is something not fitting into Joseph Lucas theory. Back from 150mls of r .......
369: Tube DIY Asylum, congrats ... and schematic?? (0.00)
Posted by gluca on 2009-07-21, 12:01:35 (87.10.251.34)
that looks neat and nice. gianluca .......
370: MagneQuest/Peerless Forum, EXO99 for me. Thanks (0.00)
Posted by gluca on 2009-07-20, 05:56:27 (87.6.198.54)
They are the perfect choice for driving triodes (801A, eimacs 25/35/75). I do need a R160 as well (just noticed the offer below). Any PSU choke good for choke input duty? Need 200-150VDC and 50mA. I c .......
371: MagneQuest/Peerless Forum, any moving coil step up? (0.00)
Posted by gluca on 2009-07-18, 08:52:50 (87.7.94.200)
Mike do you have anything like a dual primaries to one/two secondaries MC step up? Use? Step up the signal out of my dac. Thanks Gianluca PS: back to italy for a week ... connection flight in Philly y .......
372: Tube DIY Asylum, I am inclined to say (0.00)
Posted by gluca on 2009-07-11, 20:36:04 (72.49.240.248)
I prefer CCS for preamp duties and chokes on top of driver tubes. That's just my experience. Ciao Gianluca .......
373: Tube DIY Asylum, You don't need any test (0.00)
Posted by gluca on 2009-07-11, 20:32:48 (72.49.240.248)
CCS just sounds better on top a preamp triode. Google Gary Pimm and Walt Jung for more background on CCSs (or maybe you know their designs). Ciao Gianluca .......
374: Tube DIY Asylum, it sounds good (0.00)
Posted by gluca on 2009-06-26, 14:24:11 (74.83.201.74)
Done. I do prefer low value pots at the output of the transfomer. Go for it, you won't come back. Gianluca .......
375: MagneQuest/Peerless Forum, RE: Cosecant reveiw now up on Stereophile (0.00)
Posted by gluca on 2009-06-26, 06:02:54 (192.88.212.43)
Gordon, any chance I can visit your place, meet you and listen some real stuff? Gianluca .......
376: MagneQuest/Peerless Forum, RE: ok, so what? (0.00)
Posted by gluca on 2009-05-08, 13:37:00 (87.7.93.123)
here we are... or not? hey we gotta meet at the AMA, I lurked their site. Gianluca .......
377: MagneQuest/Peerless Forum, RE: ok, so what? (0.00)
Posted by gluca on 2009-05-03, 18:29:34 (12.39.15.210)
B7: I'd say you can ship to OH but I am leaving in a few days and be back mid May ... so let's wait a bit. I'll drop a mail when I am ready. XB12STT: here is a direct link ... sorta motard, it looks l .......
378: MagneQuest/Peerless Forum, ok, so what? (0.00)
Posted by gluca on 2009-04-29, 21:20:59 (12.39.15.183)
Mike, I am in Cinci. yet not for good but almost done with my move. so what? well, I need to play some music so I need to build my gear. as I wrote time ago I'd like to play with penthodes and the com .......
379: MagneQuest/Peerless Forum, My take (0.00)
Posted by gluca on 2009-04-29, 21:09:59 (12.39.15.183)
Ciao 1. OK, I like OPTs ... that's it. you really want to get ni lams. 2. been there. go for it. search for some old langevin or daven stepped attenuator. you won't find anything better out there. in .......
380: High Efficiency Speaker Asylum, thanks! that JBL thing (0.00)
Posted by gluca on 2009-04-06, 23:53:34 (195.64.188.30)
I'll be in Cinci next week. Yes, very bad news here in Italy. A friend of mine lost her family house and almost everything. Every 10yrs there is a terrible heartquake here. I feel so sorry for those p .......
381: High Efficiency Speaker Asylum, charged capacitor? (0.00)
Posted by gluca on 2009-04-06, 12:18:32 (93.38.159.173)
Jeff, I don't think I am familiar with that. Any details? thanks Gianluca .......
382: K&K Audio / Lundahl Transformers, FIxed Bias? (0.00)
Posted by gluca on 2009-03-18, 13:35:39 (89.96.14.247)
Ciao Kevin any experience with fixed bias for the GM? I must agree, GM70 is really a great tube and dirty cheap: I run a group buy for (graphite) GM's and we had them for 20USD apiece. I had good luck .......
383: Tube DIY Asylum, I will keep you posted. (0.00)
Posted by gluca on 2009-03-13, 08:28:10 (87.10.252.154)
Thanks. I am having issues with the VISA but I hope my company will fix it in those very days. Gianluca .......
384: Tube DIY Asylum, HEY! (0.00)
Posted by gluca on 2009-03-13, 05:18:26 (87.10.250.235)
I am moving to Cinci in April (Visa pending). Sure! Let's get in touch. Gianluca .......
385: MagneQuest/Peerless Forum, RE: Upgrading Older Wavelength Cardinals (0.00)
Posted by gluca on 2009-03-11, 01:08:41 (195.64.188.30)
Ciao, probably Gordon himself will reply to your mail with more suggestions but I am on the opinion that 8 or 12 W would not make a big difference so if you will look for a different amp have this in .......
386: MagneQuest/Peerless Forum, ---) Easy (0.00)
Posted by gluca on 2009-03-07, 10:58:45 (89.96.14.247)
I rode XB9SX, the smallest. I'd say I am quite (positively) surprised. I was prepared to an uncomfortable ride but uh! oh! that funny bike is good also for day trips. Seat is OK, you stay very upright .......
387: MagneQuest/Peerless Forum, Buell ... (0.00)
Posted by gluca on 2009-03-05, 09:31:21 (195.64.188.30)
>Have you looked at the buell lineup? I have. I will have a test ride this weekend. They are sharp, but I am on the impression they are not so comfortable for day trips as you said. You are right, the .......
388: MagneQuest/Peerless Forum, more sport ... (0.00)
Posted by gluca on 2009-03-03, 12:01:00 (89.96.14.247)
Nice puppy indeed. I like XR even more. Sportsters are the most sold HD's here. But price makes me wonder, I mean XR1200 is sold at 12000 euro here in Italy. With the same money or even less I can buy .......
389: MagneQuest/Peerless Forum, as long as you... (0.00)
Posted by gluca on 2009-02-21, 10:41:31 (89.96.14.247)
... work on our transformers we are happy :-) OK. We are happy also if you ride your Guzzi. Just back from the loval HD deler to have a look to the new iron sportster. I belive I really like it. Thank .......
390: MagneQuest/Peerless Forum, Ping MQ (0.00)
Posted by gluca on 2009-02-20, 12:24:54 (89.96.14.247)
Mike, you got mail on B7 and a custom OPT for the 75TLs. Did you get it? Ciao Gianluca .......
391: K&K Audio / Lundahl Transformers, RE: Interstage for 35TG tube (0.00)
Posted by gluca on 2009-02-10, 13:56:08 (87.6.197.75)
Nice tube (the 304TL)! Probably the best thing you can do is to build a mu follower using a CCS load on the 35TG and drive a parafeed transformer (I assume you will split the signal to drive the PP gr .......
392: MagneQuest/Peerless Forum, Kenwod town centre area - ) starbuck neck (0.00)
Posted by gluca on 2009-02-05, 09:55:44 (195.64.188.30)
I am no expert, but the trans coupled DACs I experimented with sounded good while I had poorer results with very few IVs I had in my hands (tube and SS). I didn't spend so much time on the subject. I .......
393: MagneQuest/Peerless Forum, E Galbraith Road: it looks to be a nice place. Does it? (0.00)
Posted by gluca on 2009-02-04, 11:14:52 (89.96.14.247)
I believe DACs (USB, Firewire, wireless, ethernet, whatever) are the source for the future. CDs and DVDs are almost dead. Vinyl will survive (I hope). Probably also HD media players will die as bits c .......
394: MagneQuest/Peerless Forum, Take care nt (0.00)
Posted by gluca on 2009-02-03, 11:59:37 (89.96.14.247)
. .......
395: MagneQuest/Peerless Forum, OK ... an idea (0.00)
Posted by gluca on 2009-02-03, 11:47:39 (89.96.14.247)
Do you like it? Problem is that EL519 wants a 5KCT tranny when operated in screen mode (as it looks like a 650 Rp triode and I like higher loads) while it needs 2KCT + UL when used as a penthode. Any .......
396: MagneQuest/Peerless Forum, RE: guess it is appropiate to say.... (0.00)
Posted by gluca on 2009-02-03, 10:00:50 (195.64.188.30)
I think we can merge the compact amp with the screen mode ... a grid choke was the very first thing I thought ... what a samm world ;-) .......
397: MagneQuest/Peerless Forum, Sold! (0.00)
Posted by gluca on 2009-02-03, 09:57:30 (195.64.188.30)
The compact amp is sold to that italian guy. I like it. There's room to replace the cathode R with a CCS to make the tail longer, low voltage, decent power, cheap, very few parts. I'll dig into it. Gi .......
398: MagneQuest/Peerless Forum, Something like that ... (0.00)
Posted by gluca on 2009-02-03, 08:28:48 (195.64.188.30)
... or maybe a DC coupled amp like Pimm's. I found a very nice idea ... I think I'll try it. Any experience/comments on similar amps? .......
399: MagneQuest/Peerless Forum, GE family (0.00)
Posted by gluca on 2009-02-03, 08:26:47 (195.64.188.30)
Ciao Gordon, I stil don't know where to look for houses... most probably I will inherit the house a friend of mine will free in March. I can't rememeber where it is, he told me it is in a nice place v .......
400: Tube DIY Asylum, Is that a custom socket? (0.00)
Posted by gluca on 2009-02-02, 11:26:26 (89.96.14.247)
ugly tubes :-) .......
401: MagneQuest/Peerless Forum, Moving to USA, the land of penthodes. (0.00)
Posted by gluca on 2009-02-02, 11:12:46 (89.96.14.247)
Folks, I am waiting for my visa and I assume in march I will move to Zinzinnati. I'll bring with me my HD full of lossless music and a DAC I am working on. I will need a preamp/amp and speakers. Proba .......
402: Tube DIY Asylum, Thanks (0.00)
Posted by gluca on 2009-02-02, 11:01:37 (89.96.14.247)
Fil seems as bright as other tubes. VT127A looks really odd, doesn't it? I'll take one or two more from Jeff, we had a good deal last year. .......
403: Tube DIY Asylum, RE: EIMAC saga (continues) (0.00)
Posted by gluca on 2009-02-01, 12:51:33 (89.96.14.247)
OK. The blue is gone. But the tube is not passing as much current as the other 75THs I have. Running at 0V at the grid and 600V at the plate I should have 40-50mA but only 10-15mA flows. Mah?! I belie .......
404: Tube DIY Asylum, I'll try to overheat the filament ... (0.00)
Posted by gluca on 2009-02-01, 12:00:49 (89.96.14.247)
... say +10% or so. Now back to prepare the PCBs for the mosfets... I hate making PCBs :-( Ciao .......
405: Tube DIY Asylum, I'd say it does not (0.00)
Posted by gluca on 2009-02-01, 07:39:56 (89.96.14.247)
as the plate current is pretty low. I don't understand whats wrong. :-( .......
406: Tube DIY Asylum, EIMAC saga (continues) (0.00)
Posted by gluca on 2009-02-01, 06:29:53 (89.96.14.247)
Folks, thanks for the suggestions I had days ago. The 75TH was glowing blue and I heated it with a strong anode current: the plate was cherry. The blue glow suddenly disappeared (after 1 minute or so) .......
407: Tube DIY Asylum, OK ... I'll try again. thx. nt. (0.00)
Posted by gluca on 2009-01-22, 13:50:19 (89.96.14.247)
. .......
408: Tube DIY Asylum, Rewind! It didn't work (0.00)
Posted by gluca on 2009-01-22, 13:30:52 (89.96.14.247)
900V on the plate and grid at ground. Heated for 10 secs. I repeated the cure 5-6 times but the blue cloud is still there. Only 10 secs as something in the PSU was hissing and I used my 75TL amp and n .......
409: Tube DIY Asylum, Thanks all. (0.00)
Posted by gluca on 2009-01-22, 00:07:43 (195.64.188.30)
I'll cook it. It's a tube I got for cheap on ebay and sold as NOS. It looks absolutely new infact. Jeff yours are strong and good. I am waiting for my L1 visa: I should land on the other side of the o .......
410: Tube DIY Asylum, More Eimacs queries (0.00)
Posted by gluca on 2009-01-21, 14:16:46 (89.96.14.247)
Eimacs experts?! Hey, I am breadbording my last amp and I am using 75THs as driver. One seems to be gassy as a blue glow is filling the whole tube. It is light blue and it looks just like a mercury r .......
411: Computer Audio Asylum, Somebody (0.00)
Posted by gluca on 2009-01-04, 08:54:31 (87.16.248.33)
Well, the realtek gets a spdif. The AE gets PCMs. Who is converting PCMs into SPDIF? It must happen inside the AE. OK, I am not going to open mine, it's brand new. Not for the time being :-) ::: TOPIC .......
412: Computer Audio Asylum, RE: Airport express audio format (0.00)
Posted by gluca on 2009-01-04, 08:23:02 (87.16.248.33)
So I am not supposed to use it or I am not supposed to be an audiophile. -LOL- Well I am not actually. I just like music and tubes. As far as i konw the old AE uses PCM270x that supports up to 48kHz. .......
413: Computer Audio Asylum, Airport express audio format (0.00)
Posted by gluca on 2009-01-04, 07:32:37 (87.16.248.33)
Gang I know the old airport express (811.g) supports only 16/44.1 files. Does the newest (811.n) go up to 24/96? Why that limit? Gianluca .......
414: Tube DIY Asylum, mmmm ... (0.00)
Posted by gluca on 2008-12-27, 06:58:45 (87.11.253.70)
Me too, I strongly suggest you to get rid of the xover after the amp. I built a 600ohm line level xover based on a LCL network. So there is the preamp, the xover and 2 amps for each channel (low+mid/h .......
415: MagneQuest/Peerless Forum, RE: EXO173 Q (0.00)
Posted by gluca on 2008-12-25, 09:05:11 (82.59.230.64)
Mine are ni lams. A great piece of iron. I used it as splitter to drive a PP stage, 2:1 output for a pre (I believe I used 801A at that time) and 1:2 interstage. Now it will be driving a pair of mosfe .......
416: MagneQuest/Peerless Forum, thanks (0.00)
Posted by gluca on 2008-12-25, 03:52:56 (87.7.93.242)
Merry Xmas gang! The idea is to see as much places in USA as possible during my free time ... I'll pay a visit to Philly as well :-) Ciao GIanluca .......
417: MagneQuest/Peerless Forum, EXO173 Q (0.00)
Posted by gluca on 2008-12-24, 12:25:43 (87.7.94.114)
Whats the copper resistance of the EXO173? I have not them in my hands now I'd need the DCR to cranck some numbers in spice for my new amp. Thanks Gianluca OH! I'll move to USA next Spring. Cincinnati .......
418: MagneQuest/Peerless Forum, + fixed bias at the grid ... (0.00)
Posted by gluca on 2008-12-10, 11:04:14 (89.96.14.247)
... ouch ... I was thinking on those cobalt B7s.... tooooo late .......
419: Computer Audio Asylum, Mac's dacs (0.00)
Posted by gluca on 2008-11-29, 15:52:53 (89.96.14.247)
OK. What DAC is Apple using in Airports and Minis and Macbooks etc?? I know in the old AE they used the Burr Brown PCM2705, and now? Gianluca .......
420: MagneQuest/Peerless Forum, B7 10K:10k? (0.00)
Posted by gluca on 2008-11-29, 15:32:43 (89.96.14.247)
I still need a pair in nickel lams. I am done with the 75TLs and breadbording the FETs amp. Gianluca .......
421: Tube DIY Asylum, I was ... (0.00)
Posted by gluca on 2008-11-27, 15:02:45 (89.96.14.247)
I was running as I dismantled that amp long ago. I tried it at 650V and 900V. Current set to 100mA in both cases. Up to +20W with a 10K:8 OPT at 900V. I guess it must have been 5W at lower voltage. Mi .......
422: Tube DIY Asylum, Me ... (0.00)
Posted by gluca on 2008-11-27, 12:57:09 (89.96.14.247)
... I am using a pair of 211's by penta and I am quite happy with them. Frankly speaking they do not miss anything from vintage GEs. Penta tubes are made by shuguang Nice tube the 813. I used it triod .......
423: Computer Audio Asylum, Interesting side note ... (0.00)
Posted by gluca on 2008-11-25, 08:25:23 (195.64.188.30)
... so you copied all the music onto your laptop and fed the DAC? This is unfortunate as the esternal HD would have been my preferred storage to access music from. .......
424: Computer Audio Asylum, I am looking to studio II (0.00)
Posted by gluca on 2008-11-24, 16:04:57 (89.96.14.247)
I have been told they are really quiet and they are dual drivers. Any feedback on them? Gianluca .......
425: Computer Audio Asylum, HD suggestion (0.00)
Posted by gluca on 2008-11-24, 07:57:35 (195.64.188.30)
Guys, I decided to copy all my CDs onto an external HD. I'll use macbook pro + airport + SPDIF DAC to feed music onto the amps+speaker. I believe 500GBs would be enough. But, all the feedbacks I am re .......
426: MagneQuest/Peerless Forum, Next step (0.00)
Posted by gluca on 2008-11-22, 09:40:17 (89.96.14.247)
Next step I am taking is to sell my old tascam cd player and buy an airport express and an external 1TB HD with that fresh cash. I will link the airport straight onto the DAC via SPDIF/USB: no more ca .......
427: Tube DIY Asylum, RE: DHT preamplifiers- Do they all lack density?(long) (0.00)
Posted by gluca on 2008-11-21, 07:53:42 (195.64.188.30)
Mah!? I use a 211 in my pre and I am 95% satisfied with. I just need to revisit the filament supply. I know friends that are 100% satisfied with JFets. Gianluca .......
428: MagneQuest/Peerless Forum, OK. I owe you a beer ... (0.00)
Posted by gluca on 2008-11-20, 14:46:52 (89.96.14.247)
... :-) Gianluca .......
429: MagneQuest/Peerless Forum, I'll pay the drinks ... (0.00)
Posted by gluca on 2008-11-20, 13:25:41 (89.96.14.247)
... so far no problems with macs after 10 or 15 years. Only safari goes nuts with ebay on certain occasions (just like mozilla). Been lucky? I love macs. .......
430: MagneQuest/Peerless Forum, Get a mac. (0.00)
Posted by gluca on 2008-11-19, 15:13:24 (89.96.14.247)
I do not have anything more to add. Just get a mac. Gianluca .......
431: MagneQuest/Peerless Forum, That's pretty interesting! n/t (0.00)
Posted by gluca on 2008-11-02, 02:00:29 (83.225.175.107)
thanks. .......
432: MagneQuest/Peerless Forum, Best thing to do ... (0.00)
Posted by gluca on 2008-11-01, 11:21:32 (83.225.55.193)
... with filament chokes is to make a LCL filter (double it for drivers). And this is (in my humble experience) the best way to heat DHT's (when DC is compulsory). The first L can be replaced with a r .......
433: Tube DIY Asylum, electrical tape and fingers (0.00)
Posted by gluca on 2008-10-30, 00:17:50 (83.225.22.83)
MUAHHAHA! I need to give that transmitting tape a try :-) FIlament supplies: I do use a last choke too. Back-to-back test showed clearly I do need it. And I am using dual bobbins chokes too after the .......
434: Tube DIY Asylum, Q's (0.00)
Posted by gluca on 2008-10-29, 15:35:02 (91.80.215.22)
Heya Dave, pretty much like my 801A/75TL amp. Well, a couple queries 1) why a ni choke in the PSU? 2) I am using LLCLCL for both the driver and power tube filaments with no pot ("asymmetrical" groundi .......
435: Tube DIY Asylum, Reflections and imperfections (0.00)
Posted by gluca on 2008-10-22, 15:19:49 (77.221.181.106)
That's the world we live in. Imperfect on both the ends... :-) I will cure the 801A and tune that parafeed cap, that's an easy and fast issue to fix. Thanks for the tips. All that said, I will repeat .......
436: Tube DIY Asylum, I think ... (0.00)
Posted by gluca on 2008-10-22, 04:55:18 (195.64.188.30)
I think I got it. The 801A is choke loaded with iron gapped for 20mA, I am abusing it with 25-30mA. The drop of the inductance would explain the loss of gain at low freqs. I'll cure the problem biasin .......
437: Tube DIY Asylum, I will... (0.00)
Posted by gluca on 2008-10-21, 23:19:36 (89.96.14.247)
The overall bandwidth is "restored" but I really can't see what the problem is with the 801A. I will repeat the measurements stage by stage in isolation. Ciao Gianluca OH! Yes ... the 75TL is so sweet .......
438: Tube DIY Asylum, more 75TL (0.00)
Posted by gluca on 2008-10-21, 11:57:55 (89.96.14.247)
Here we are. The chart plots for each stage the ratio 20*log(out/in) referenced at 1kHz. I'll make myself more clear. The graph for the 801A is the ratio of its plate signal to its grid signal in dB, .......
439: Tube DIY Asylum, Give them to me :-) (0.00)
Posted by gluca on 2008-10-21, 00:04:15 (195.64.188.30)
LCLCL. I wil let you know the value of components. (memory's failing) Gianluca .......
440: Tube DIY Asylum, I'll see... (0.00)
Posted by gluca on 2008-10-21, 00:01:57 (195.64.188.30)
... I'll take measurements at the main points in the amp: input, driver, plates etc... But yes, thats a great sounding amp. .......
441: Tube DIY Asylum, RE: Anyone tried an interstage SE parafeed to Push Pull?? (0.00)
Posted by gluca on 2008-10-20, 13:31:29 (89.96.14.247)
I did. Worked out to be a good solution. I used it also with 10mA unbalanced (SE:PP) with no problem at all. I used 6H30 and 6N6 as driver. Best thing I did with that amp was installing an EXO173 spli .......
442: Tube DIY Asylum, More on 75TL (Ed Sawyer's bass) (0.00)
Posted by gluca on 2008-10-20, 12:48:19 (89.96.14.247)
I plugged the oscope onto the 75TL amp and what I got is 20Hz: -2.6dB 20kHz: -1.6dB The same amp with the 304TL sports 20Hz: -1.7dB 20kHz: -0.8dB and performs (much) better on square waves. Power for .......
443: Tube DIY Asylum, 2A3 as driver maybe? (0.00)
Posted by gluca on 2008-10-18, 12:59:47 (89.96.14.247)
lower Rp and more current. Ciao Gianluca .......
444: SET Asylum, Thanks (0.00)
Posted by gluca on 2008-10-18, 11:19:22 (89.96.14.247)
Just try. Just mind the high voltage. Thanks for the kind words. Gianluca .......
445: SET Asylum, That's actually a problem (0.00)
Posted by gluca on 2008-10-18, 11:18:24 (89.96.14.247)
I think I need to build a cage around the amps. I will move, in the new installation I will protect the amps from curious fingers. Hey! Do not touch my amp! Me too, sometime I am scared and I am prett .......
446: Tube DIY Asylum, what OP? (0.00)
Posted by gluca on 2008-10-18, 11:14:43 (89.96.14.247)
I was aiming at something around 400V/20mA. CCS loaded. Gianluca .......
447: Tube DIY Asylum, Jeff! (0.00)
Posted by gluca on 2008-10-18, 11:13:38 (89.96.14.247)
Thanks again for the ultra-safe shipping. I am with you on the ratings. Usually I ran the tubes at 1/3 - 1/2 of the max dissipation. Changing the bias is a matter of seconds, I just need to solder a d .......
448: Tube DIY Asylum, No problems... (0.00)
Posted by gluca on 2008-10-18, 11:08:20 (89.96.14.247)
... Ed, I am going parafeed with those puppies. 90H on top of the anode and a beefy OPT. Both by Mike MQ. The 304TL amp makes a -1.5 dB at 20Hz. I don't know where the 75TL goes but i don't miss any b .......
449: Tube DIY Asylum, Muahahha (0.00)
Posted by gluca on 2008-10-18, 11:01:31 (89.96.14.247)
Me too :-) (well, actually I use those 211's) ... you know I am going to use 75THs to drive a mosfet power stage? I love those odd bottles. Muahahahah .......
450: Tube DIY Asylum, and ... (0.00)
Posted by gluca on 2008-10-18, 06:56:03 (89.96.14.247)
... it seems this 75TL is biasing perfectly as per your curves. Thanks. Gianluca .......
451: Tube DIY Asylum, RE: What OP for the 75TL (0.00)
Posted by gluca on 2008-10-18, 06:51:20 (89.96.14.247)
Thanks Dave, 50:1 here too (now running 33:1 into 16ohm horns). I think I'll raise a bit the current up to 60 or 65mA. .......
452: Tube DIY Asylum, nah (0.00)
Posted by gluca on 2008-10-18, 05:46:39 (89.96.14.247)
I am using 211 for the line stage ;-) .......
453: Tube DIY Asylum, What OP for the 75TL (0.00)
Posted by gluca on 2008-10-18, 05:01:37 (89.96.14.247)
What OP for a 75TL running at 900V B+? I biased it at 50mA, any better choice? Gianluca .......
454: SET Asylum, The real problem is ... (0.00)
Posted by gluca on 2008-10-18, 04:08:09 (89.96.14.247)
... that you need more than a SET to enjoy them. Here it comes my latest amp (a few final trimmings still needed): the 304TL is driving the bass bin and the 75TL the horns. What else? Well, I've been .......
455: MagneQuest/Peerless Forum, triode strapped? (0.00)
Posted by gluca on 2008-10-11, 15:21:19 (89.96.14.247)
I would say 4uF. Just try a couple of cheap ones around that value, then buy your preferred brand/type. Ciao .......
456: Tube DIY Asylum, RE: Doing some filament amperage math.... (0.00)
Posted by gluca on 2008-10-07, 14:08:45 (81.208.60.207)
hum ... actually the problem might be with the transformer and not with the tubes. frankly speaking I doubt it will be really a problem. 1.45A can be a problem for some LDO devices (power and current .......
457: Tube DIY Asylum, Watt (0.00)
Posted by gluca on 2008-10-03, 03:14:00 (195.64.188.30)
Frankly speaking I can't remember. I guess it should be Ciao .......
458: Tube DIY Asylum, RE: 807 in srpp (0.00)
Posted by gluca on 2008-10-02, 14:29:34 (81.208.60.207)
YW. That will be a long project. Expensive too. But 813 can really sing. Have fun. .......
459: Tube DIY Asylum, RE: 807 in srpp (0.00)
Posted by gluca on 2008-10-02, 14:21:29 (81.208.60.207)
I would you suggest you to use a fully passive DC heater: bridge-C-L-C-L. You really want to use that last L. I have used also a CLC +current regulator but it was really hot. Both sound good. Anode d .......
460: Tube DIY Asylum, RE: 807 in srpp (0.00)
Posted by gluca on 2008-10-02, 14:04:07 (81.208.60.207)
And how do you get 20Vpp? And are you planning to drive the 813 from the upper cathode (i.e. the standard SRPP) or from the lower anode? I liked the 813, quite cheap and superior build quality. I woul .......
461: Tube DIY Asylum, RE: 807 in srpp (0.00)
Posted by gluca on 2008-10-02, 13:18:30 (81.208.60.207)
haem ... actually I used the 801 to drive the 813. The 807 and the choke acted as a CCS. Complex because there are too many parts :-) my current amps have two tubes and a few more parts (1 input trann .......
462: Tube DIY Asylum, RE: 807 in srpp (0.00)
Posted by gluca on 2008-10-02, 11:31:49 (81.208.60.207)
807 as a triode? A bit less than 8. I made this amp a couple of years ago: it sounded quite good but it was way too complex for my tastes .......
463: MagneQuest/Peerless Forum, RE: ten albums to hear before you check out.... (0.00)
Posted by gluca on 2008-09-27, 16:56:59 (81.208.60.207)
I have just two out of those 10. The dark side of the moon and the Joshua tree. HEY! They missed many many many better albums gl .......
464: MagneQuest/Peerless Forum, Details on Power supply? n/t (0.00)
Posted by gluca on 2008-09-19, 08:18:41 (87.7.95.123)
. .......
465: High Efficiency Speaker Asylum, Way too much ... (0.00)
Posted by gluca on 2008-09-15, 04:35:06 (87.2.91.9)
1500$/pair? OH! I would be prepared to pay up to 700$ for a pair and in nice working conditions with genuine diaphgrams. The price is right as long as someone is willing to pay it. Gianluca ::: TOPIC: .......
466: Tube DIY Asylum, lol (0.00)
Posted by gluca on 2008-09-14, 01:06:32 (87.11.252.116)
Maserati, MV Agusta, Ducati Have fun Gianluca .......
467: Tube DIY Asylum, been there ... (0.00)
Posted by gluca on 2008-09-13, 13:44:56 (87.7.249.182)
... but i do prefer LCL coupling or direct coupling. .......
468: MagneQuest/Peerless Forum, RE: EXO-173PPS (0.00)
Posted by gluca on 2008-09-13, 13:43:34 (87.7.249.182)
You can use the LCL calculator I made or the voltsecond's (what a guy! his model is much more complete than mine). The calculators are made for output stages but if you input the OPT reflected load as .......
469: MagneQuest/Peerless Forum, RE: EXO-173PPS (0.00)
Posted by gluca on 2008-09-13, 11:44:47 (82.59.228.162)
OH! 100H is quite a bunch of henrys. I "loaded" with no issues at all drivers up to 6k with a EXO173 with ni lams. What tube are you using? .......
470: Tube DIY Asylum, I met him ... (0.00)
Posted by gluca on 2008-09-07, 17:02:13 (83.225.31.205)
.. in May. He is still in business and he told me he will sell his transformers directly so best thing you can do is to drop him a mail. I saw he is using now very cool (and gigantic) black hammered c .......
471: Tube DIY Asylum, RE: Some help with Daven Attenuators... (0.00)
Posted by gluca on 2008-09-07, 05:41:48 (87.7.95.112)
I use (used actually) them in a passive line-level crossover (600hm) to attenuate highs/lows as required. You can use them as a volume control if you have a transformer coupled preamplifier (at the ou .......
472: K&K Audio / Lundahl Transformers, schematic (0.00)
Posted by gluca on 2008-09-03, 13:21:30 (91.80.91.203)
sorry for the bad quality of the draft. this was a low voltage version of the spud amp to drive my headphones (the input tranny was an ex-BBC by sowter later on replaced by a LL1540, a homebrew tranny .......
473: K&K Audio / Lundahl Transformers, RE: Which SE amp should I build next? (0.00)
Posted by gluca on 2008-09-03, 07:33:00 (87.7.95.94)
I built a 6C45p amp a while ago and liked it. Do not expect much more than 1.5W so keep in mind you would prefer to use a 100+dB speakers. Anyway I strongly suggest to use a fixed bias at the grid (ba .......
474: Tube DIY Asylum, More ... (calling MQ too) (0.00)
Posted by gluca on 2008-09-01, 07:29:52 (87.6.197.26)
Ciao Dave, the 304TL is now choke loaded (90H) and cap coupled to a parafeed tranny. I can hook it up as 10K:16, 9 or 4. The primary inductance seems to be very high. 10K:4 is 50:1 voltage ratio that .......
475: Tube DIY Asylum, Calling eimacs experts again (0.00)
Posted by gluca on 2008-09-01, 04:28:27 (87.2.199.92)
Folks, I am running my 304TL amps and I could convert them to 75TLs with a few mods to the filaments and a different hookup of the OPT. Thinking of 900V/35V/70mA as bias point. Should I do that or not .......
476: Tube DIY Asylum, is there anything else close to the amp ... (0.00)
Posted by gluca on 2008-08-23, 13:01:49 (87.7.249.69)
... TV, monitors, PCs? well, does it matter if you listen close to the amp? Sorry, couldnt resist .......
477: Tube DIY Asylum, RE: Silicone rectifiers (0.00)
Posted by gluca on 2008-08-21, 06:29:39 (87.11.252.221)
I use teflon tubes and solid wire (silver, but that does not mean anything). Mind your hands, 900V are much higher than you think. G .......
478: Tube DIY Asylum, filament is ok. no further test so far (0.00)
Posted by gluca on 2008-08-18, 02:58:18 (87.10.88.99)
all other nos eimac I had were perfect but a single 304TL whose half filament just doesn't light up even if it is not broken ... odd, isn't it? .......
479: Tube DIY Asylum, Now I have ... (0.00)
Posted by gluca on 2008-08-17, 16:05:25 (91.80.161.118)
4 75TLs ... NOS. I am happier :-) Going to build something next fall re .......
480: SET Asylum, Hey! (0.00)
Posted by gluca on 2008-08-15, 06:45:38 (87.10.252.104)
Do you really need all those caps? .......
481: Tube DIY Asylum, I am a fan... (0.00)
Posted by gluca on 2008-08-11, 01:14:03 (87.2.91.246)
... of input trannies and xlr connex. HEY! You were supposed to use as much iron as possible! :-) .......
482: Tube DIY Asylum, same here. a question (0.00)
Posted by gluca on 2008-08-10, 07:48:49 (87.11.252.128)
Dave same topology here but with 801a and 304tl. Do you prefer to bias the driver at the cathode or at the grid using again batteries? Gianluca .......
483: SET Asylum, Hey! (0.00)
Posted by gluca on 2008-07-05, 08:07:23 (91.80.133.192)
Just to be 100% sure ... I float the CTs at the transmitting and receiving ends of the output and input transformers (ie the windings that are driving the interconnect cable). Do not float the CT of t .......
484: SET Asylum, Give floating CT a try (0.00)
Posted by gluca on 2008-07-04, 18:13:26 (83.225.134.150)
I preferred it. Can't remember why and when. Got used to floating CTs now. Ciao .......
485: SET Asylum, I am using bal connections (0.00)
Posted by gluca on 2008-07-04, 16:13:26 (83.224.168.45)
A balanced connection is not a "differential" signal. I am not transmitting a differential signal across my balanced line (my transformers are floating) but my SE stage is amplifying the differential .......
486: SET Asylum, RE: why PP signal for SE amplification? (0.00)
Posted by gluca on 2008-07-04, 15:11:13 (83.225.14.108)
I didn't say I use a PP signal. I said I use balanced connections. In my mind all the tubes are amplifying the difference between the signal (grid) and the ground (cathode) so why shouldn't I use the .......
487: SET Asylum, My SET amps and preamps have Balanced Inputs (0.00)
Posted by gluca on 2008-07-04, 00:16:19 (195.64.188.30)
I do use input transformers. Gain depends on the transformers, noise can be an issue if the transformer is not placed properly and overall quality of the sound can be impaired. All that said, get your .......
488: MagneQuest/Peerless Forum, ---) Pinging mr LeFevre (0.00)
Posted by gluca on 2008-07-03, 01:27:50 (195.64.188.30)
Mike! I don't know if you had a look to my latest mail. I found an arrangement that let me use the EXO173PPS as it is. Great! I'll drop a schematic for your info as I'll be back home. Ciao. Thanks. Gi .......
489: Tube DIY Asylum, link again pls (0.00)
Posted by gluca on 2008-07-01, 09:12:28 (195.64.188.30)
I could not find fairrite. Thanks .......
490: Tube DIY Asylum, I will try ... (0.00)
Posted by gluca on 2008-07-01, 02:06:20 (195.64.188.30)
If things turn out to be bad I will replace the SMPS with CLCLC as in the other amps. Yes they are in the signal path ... unless you place a choke at the filaments: that would present quite an high im .......
491: Tube DIY Asylum, CJ... (0.00)
Posted by gluca on 2008-06-30, 14:15:09 (83.225.15.94)
I am going to heat up a 75TH. The baby is asking for a whopping 6.25A@5V... SLAs are out of question. Did you notice any interference with SMPS on? .......
492: Tube DIY Asylum, You telling me ... (0.00)
Posted by gluca on 2008-06-30, 13:38:59 (83.224.135.145)
Are you telling me I need all the irons and caps to LCLC the filaments and forget the SMPS. OH! That's going to be heavy. I found a nice link on the subject .......
493: Tube DIY Asylum, Ok ... but (0.00)
Posted by gluca on 2008-06-30, 12:25:47 (83.225.144.234)
I will use the SMPS in a separate shielded case. I have also mumetal sheets savaged from somewhere. But did you have any issues? Gianluca .......
494: Tube DIY Asylum, What do you mean? N/T (0.00)
Posted by gluca on 2008-06-30, 09:37:33 (195.64.188.30)
. .......
495: Tube DIY Asylum, RE: Switching PS for filaments (0.00)
Posted by gluca on 2008-06-29, 12:53:39 (91.80.150.223)
This seems to be a candidate. Heck! It costs 9.95USD in US ... in Italy I find something pretty similar for 90USD at the major on line shops! I just can't believe it. BTW I noticed that SMPS have typi .......
496: Tube DIY Asylum, More (0.00)
Posted by gluca on 2008-06-29, 10:05:08 (83.225.167.149)
Thanks for the replies. The SMPS will be AC-DC. I am wondering about the fan (they are very noisy) and distance from signal wiring and parts. OH! Ebay didn't turn out with anything interesting so far. .......
497: Tube DIY Asylum, RE: Switching PS for filaments (0.00)
Posted by gluca on 2008-06-28, 13:57:58 (83.225.7.180)
I need them for a 75TH too... haem ... I have your 75TH/300B schematic just on my desktop. Nice job Ed, congrats. JJ suggested me to use SMPS for my 304TLs but at the end I used CLCLC filtering so I h .......
498: Tube DIY Asylum, Switching PS for filaments (0.00)
Posted by gluca on 2008-06-28, 12:32:23 (83.225.144.83)
I know someone out there is using SMPS to light up big tubes. I never dealt with SMPS as I have only used low drop out regulators and fully passive (LC) solutions for my tubes. But I have no space and .......
499: Tube DIY Asylum, Same here: min is 2.5V ... (0.00)
Posted by gluca on 2008-06-22, 14:38:20 (82.59.230.95)
... and DO NOT use any cap after the reg. Anyway a (C)LC is necessary before the regulators to cut the hi freqs injected by the bridge. Gianluca .......
500: Tube DIY Asylum, Yes, a (2nd) choke. Or a CCS n/t (0.00)
Posted by gluca on 2008-06-22, 01:13:23 (87.10.252.40)
. .......
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