2. amps-preamps
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Swap out 12bz7 in favor of 12ax7?

I've asked this question before, but maybe wasn't specific enough so I thought I'd try again. I have a Cary V12r amp which has two 12bz7 tubes in the signal path. I understand that the 12bz7's are a high-gain alternate to the 12ax7. The question is, in this amplifier, could I take out the 12bz7 tubes and replace them with the lower gain 12ax7 tubes? I know a fair number of A-Goners have switched from the 12ax7 to the 12BZ7 for the added gain but I'm looking for the the opposite. Any thoughts?
grimace
elevick
2,636 posts
 
I found most 5751 tubes to be a little "dryer" or less tubey than 12ax7s. Let me see what I have laying around for you.
Did you ask him about 7189 instead of EL84?
grimace OP
624 posts
 
The EL84s aren't really in the signal chain. He said the 12BZ7s would be a better place to start.
grimace OP
624 posts
 
Sorry, I transposed that tube number. It should be a 6072A.
grimace OP
624 posts
 
Just to follow up on this. I got my amp back today from Cary and did a quick A/B comparison between the 12bz7 and the 12ay7s and, indeed, the output volume with the 12ay7's is lower than the 12bz7's, requiring a little more volume on the pre-amp. Didn't have an opportunity to do any extended listening, but there was very little to differentiate the sound quality of between the tubes. I'll look forward to a lengthier session.
ebm
9,311 posts
 
Never swap tube type unless co says its ok.
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