Amp/Preamp Asylum Looking for a new Amp or Preamp? If you're after tubes, post over here.

---

[ Follow Ups ] [ Post Followup ] Thread: [ Display  All  Email ] [ Amp/Preamp Asylum ] [ Return to Search Results ]

---

[ Alert Moderator ]

---

I have absolutely no idea - - (sorry, long post)

Posted by Bambi B (A) on August 31, 2009 at 05:58:22

In Reply to: Jolida 1701 and 1301 vs 1501 posted by kll on August 30, 2009 at 07:01:45:

kll,

I've only ever heard a Jolida 1501RC in a shop for two minutes- and at odd angle, so I can't answer your question comparing the 1301, 1501, and 1701. It was not bad at all and recalling this later I considered a Jolida 1501 for my office system when space was too tight for separate components. In fact, the space was so tight I ended using a receiver.

From their looks, comments, and way they're made and marketed, my speculation is that the three Jolida hybrid integrated amplifiers probably have similar sound qualities, and it's more the power and features that varies than the detail and resolution. Probably just changing to either of the lowered powered models will not be a big help- but it might.

I've noticed over the years that with solid state- and some tube gear too, I sometimes prefer the lower powered model. In these cases, the lower powered in a series seemed sweeter and more transparent. Examples: The Marantz 2235 receiver compared to the 2275 and I like McIntosh MC30's more than MC275. I've had for 25 years a Audio Research D115 (100W tubes) and I still sometimes think that it's smaller brother, the D70 with 60W has sound qualities I prefer.

I don't know why this is- perhaps because the gain has to go up a bit with the lower power to keep the bass in the same proportion. But, certainly I seem to hear more and better detail, with more distinct timbres at higher preamp gain settings. When I play a CD through an Audio Research SP10 tube preamp, I have the SP10 set on "low gain" and the gain control at 7:30- and the results are a lessening of detail and a hardness as there is more Cambridge Audio 640C- which I find a bit dry- than SP10 coming through. - My next CD player will have a gain control.

My thought, before making a costly change to something that might have the same dissatisfying quality is to try a pair of NOS 5751 tubes in place of the 2- Chinese 12AX7's. The 5751 is electrically the same as the 12AX7, but at 70% of the gain. This will mean the gain control moves up up for the same volume level. I don't understand the technical reasons why but it seems to give the preamp some room to stretch it legs- perhaps the transients are cleaner by simply having more power applied to making them- and that means sharper detail for the consumer!

I have read comments that the current Shuangang 12AX7 is not bad- or was it the version before the last that is the better one? I have never used Chinese 12AX7s- for very long, but they're supposed to be improved. The Russian Sovtek LPS is an encouraging current 12AX7 - very quiet and is dynamic without being harsh.

If you try a 5751, my favourite is clearly the 50's Sylvania black plate, triple mica, but the RCA black plate triple mica and RCA 2- mica black plate are very good too. I've used the late grey plate GE in a microphone preamp- a tube that Tube World sold NOS for $10 then 12 then 15 for years- and these are quite good as well, but the early black plate triple mica's are in another league. Have a look at "Joe's Tube Lore" in the FAQ section here. The 5751 was discovered by the tube guitar amp crowd and can be quite expensive now, but you only need two for the 1501 and the results may save getting a different amplifier. -Just a thought.

You might also consider trying a more detailed 12AX7. The ultra-detailed 12AX7 for me is the Siemens triple mica E83CC- very energetic without ever being harsh- and very quiet. For detail, quiet, and all round excellent sound, you might consider the old RCA 7025. And: There was a Tesla copy of the frame grid Telefunken ECC803S. I bought a few of these to replace the 8-smooth plate Telefunkens in an old Fisher 800 receiver and a brief try was that the Tesla copy is really, really good! The current JJ E83CCS is also a frame grid and the successor to the Tesla, but I read the sound is not in the same class as the earlier one.

The Telefunken ECC803S must be astounding: If you follow NOS tubes you may have noticed the Telefunken has sold for up to 700 each NOS- it must be the most expensive 12AX7.

It seems worthwhile to consider a bit of tube experimentation before going to the trouble and expense of changing amplifiers.

Let us know what you do!

Cheers,

Bambi B

This post is made possible by the generous support of people like you and our sponsors:

Crux Audio

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]

---

[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]

---