12AT7...

12AT7...

Posted by Ralph (M) on September 27, 2016 at 12:48:23

In Reply to: Raising gain on 12AU7 input tube. posted by Cougar on September 27, 2016 at 10:45:47:

A 12AT7 has more gain than the 12AU7. Your ideas for raising the gain won't work, and its not that great an idea to reduce GNFB to get the gain either!

So you could try the 12AT7. The problem there is that the tube has different operating points and probably won't sound the best until the circuit is optimized for the tube. So that's not exactly an easy task unless you have soldering skills and know your way around Ohm's Law to say the least.

If I were you I would either deal with the fact that you have to turn up the volume more or talk to VTL and see if they have any solutions. Like putting the old board back in.

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

Follow Ups Full Thread

Topic - Raising gain on 12AU7 input tube. - Cougar 10:45:47 09/27/16 (19)

Sounds like from the responses that.... - Cougar 11:03:43 09/28/16 (1)

RE: Sounds like from the responses that.... - FenderLover 15:45:47 09/28/16 (0)

RE: Raising gain on 12AU7 input tube. - Naz 21:26:01 09/27/16 (1)

RE: Raising gain on 12AU7 input tube. - Cougar 10:59:08 09/28/16 (0)

The best solution - Chip647 19:03:26 09/27/16 (6)

RE: The best solution - Cougar 19:41:07 09/27/16 (5)

There is nothing wrong with that - Chip647 20:40:46 09/27/16 (4)

I will put the Weber WZ68 in...... - Cougar 21:17:19 09/27/16 (3)

RE: I will put the Weber WZ68 in...... - Tre' 07:39:38 09/28/16 (2)

I have never had to turn.... - Cougar 10:55:44 09/28/16 (1)

RE: I have never had to turn.... - Tre' 11:12:24 09/28/16 (0)

RE: Measure the voltage in/out of the preamp - Russ57 15:20:14 09/27/16 (0)

RE: Raising gain on 12AU7 input tube. - FenderLover 14:42:03 09/27/16 (1)

Yes, it's the newer low gain PCB. - Cougar 18:54:52 09/27/16 (0)

12AT7... - Ralph 12:48:23 09/27/16 (3)

RE: 12AT7... - Cougar 18:53:09 09/27/16 (2)

RE: 12AT7... - Ralph 10:07:28 09/28/16 (1)

There is one posted on the..... - Cougar 11:23:46 09/28/16 (0)

RE: Raising gain on 12AU7 input tube. - Eli Duttman 11:41:21 09/27/16 (0)

Follow Ups

12AT7... - Ralph 12:48:23 09/27/16 (3)

RE: 12AT7... - Cougar 18:53:09 09/27/16 (2)

RE: 12AT7... - Ralph 10:07:28 09/28/16 (1)

There is one posted on the..... - Cougar 11:23:46 09/28/16 (0)

Post a Message!