Pinging airtime and others regarding the 12au7 and its favored/disfavored applications

Posted by JoshT (A) on March 15, 2023 at 08:15:58

So airtime, you peeked my interest recently regarding how terrible the 12au7 tube is, at least for use in the ST-70 driver board. I know you've expressed your negative views on that tube type before, and you're certainly not the only one by a long shot who I've heard express similar views here and elsewhere on the internet.

From what I've read, it is nonlinear, has high distortion, and sounds "small" compared to other options such as the 6SN7. Among others, the folks at Vaccuum Tube Audio (Tubes4Hifi) and Dan Sachs sing the praise of the 6SN7 compared to the 12au7, but I gather it's not a plug and play replacement.

In my case, I have 12AU7s exclusively in may ST-70 and my Rogue Audio RP-5 preamp. I also have three of them in my Cronus Magnum II integrated (together with a pair of 12ax7s). Here's the thing - I like the sound of all three components a lot. I really have no complaints at all, and I generally live my the maxim "if it sounds good it is good," but on the other hand . . .

On the other hand, I also have first hand experience with upgrades that revealed to me how much I was missing before the upgrade. And strictly from a sonics standpoint, my favorite preamp was a Conrad Johnson Premier 17LS with four 6922 tubes. But that was years ago and the Rogue sure is close to my recollection and has more features and is better mannered.

So I'd love to hear from the experts in some detail what they don't like about the 12au7 compared to other options, and whether the tube's defects are only audible in some applications and not all. Also, when can one replace the other with an adapter but without otherwise changing the circuit? The 12au7 sure is plentiful, both NOS and new production, and affordable.

TIA!
___
"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."

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

Topic - Pinging airtime and others regarding the 12au7 and its favored/disfavored applications - JoshT 08:15:58 03/15/23 (23)

Why not just use a 6SN7? - andy evans 04:50:24 03/16/23 (1)

I'm going to . . . - JoshT 07:25:27 03/16/23 (0)

I have used the 12AU7 with Good results. - Cougar 09:26:45 03/15/23 (14)

Oh wow! So I could do that too with my ST-70? - JoshT 09:39:37 03/15/23 (13)

RE: Oh wow! So I could do that too with my ST-70? - Cougar 12:40:22 03/15/23 (12)

Thanks! nt - JoshT 15:43:39 03/15/23 (3)

Update: I ordered a VTA Octal pcb. - Cougar 07:39:27 03/16/23 (2)

I'm looking forward to reading about your results - 1973shovel 08:33:23 03/16/23 (0)

Excellent - JoshT 08:04:50 03/16/23 (0)

RE: Oh wow! So I could do that too with my ST-70? - Mick Wolfe 15:33:28 03/15/23 (7)

RE: " he says the 6SN7 board have been a noticeable improvement" - 1973shovel 16:08:39 03/15/23 (6)

Thanks, and one clarification question - JoshT 07:29:25 03/16/23 (5)

I continue to use the adapter - 1973shovel 08:21:37 03/16/23 (4)

I ordered an adapter - JoshT 06:48:56 03/17/23 (3)

RE: I ordered an adapter - 1973shovel 07:33:19 03/17/23 (2)

Continuity meter - 1973shovel 08:07:54 03/17/23 (1)

Thanks again! - JoshT 10:57:10 03/17/23 (0)

RE: Pinging airtime and others regarding the 12au7 and its favored/disfavored applications - Palustris 09:22:54 03/15/23 (1)

Thanks and will do. I'm still a bit green on tubes. After all, I'm only 57 LOL. nt - JoshT 09:44:38 03/15/23 (0)

the controversial 12au7 - Story 08:50:02 03/15/23 (3)

RE: the controversial 12au7 - Tre' 10:27:08 03/15/23 (1)

know all about it as discussed before - Story 10:33:53 03/15/23 (0)

Interesting. Thanks! nt - JoshT 09:45:46 03/15/23 (0)

Pinging airtime and others regarding the 12au7 and its favored/disfavored applications

Post a Message!