12ax7 vs. 12at7

Re: 12ax7 vs. 12at7

Here's a link I just found that explains the difference with different pre-amp tubes. http://thetubestore.com/gainfactor.html

It says in there that the power amp section works harder if you use a lower gain tube I wonder if it actually makes overdriven tones easier to achieve.
 
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Re: 12ax7 vs. 12at7

For some reason, 12AT7 has never been a very popular tube in the first stage either with manufacturers or with swappers. I have a box of them here of various Euro/US brands and none of them sound very good in V1. 5751 or 12AY7 (or even 12AU7) work better for me...
 
Re: 12ax7 vs. 12at7

ES350 said:
For some reason, 12AT7 has never been a very popular tube in the first stage either with manufacturers or with swappers. I have a box of them here of various Euro/US brands and none of them sound very good in V1. 5751 or 12AY7 (or even 12AU7) work better for me...
I use the 12au7 in most slots because it makes the power tube distortion more noticable.
 
Re: 12ax7 vs. 12at7

ES350 said:
For some reason, 12AT7 has never been a very popular tube in the first stage either with manufacturers or with swappers. I have a box of them here of various Euro/US brands and none of them sound very good in V1. 5751 or 12AY7 (or even 12AU7) work better for me...

That's because a 12AT7 is used more as a functional tube and not as a tube in a tonal spot in amps...It's "normally" a phase inverter tube or used to drive reverb or the vibrato circuits in Fender amps...
 
Re: 12ax7 vs. 12at7

Awesome link bro.

I'm still a little confused if there would be any problems switching my 12at7 with a 12ax7. Like frying the circuits or ?. My head has 5 preamp tubes, all Ruby's with the 1st being a 12at7 and the others being 12ax7's.

"Edit...I'm sorry the 12at7 is actually a Phillip's tube"
 
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Re: 12ax7 vs. 12at7

STRATDELUXER97 said:
That's because a 12AT7 is used more as a functional tube and not as a tube in a tonal spot in amps...It's "normally" a phase inverter tube or used to drive reverb or the vibrato circuits in Fender amps...
Wow I may be looking at my preamp backwards. My head has Reverb so the 12at7 may be in line for that.

Hmmmmm. Is there a common direction that preamp tubes run. Like from left to right or ?
 
Re: 12ax7 vs. 12at7

The preamp tube closest to the power tubes is normally the phase inverter. I'm betting the 12AT7 in question is your PI. I will often put a 12AY7 into a slot that might normally call for a 12AX7 to achieve more cleanheadroom, lower gain front end basically.
 
Re: 12ax7 vs. 12at7

Pretty much the only way you'll screw up with the "common" preamp tubes is to put an EF86 somewhere designed for the 12A@7 style tube.
 
Re: 12ax7 vs. 12at7

A 5751 tube is another choice also with a gain factor like the 12AT7....It's been stated that SRV used these tubes for more clean headroom?
 
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