What preamps & amps (including guitar) use the 12AU7 or 12AT7?

[mech986]

Always wondered about that since the 12AX7 dominated in most cases, but I've yet to see any reference where the 12AU7 and 12AT7 are used much.

I think I know the below are correct? Additional info from all you tube gurus would be helpful.

12AU7 - Heathkit W5M


12AT7 - Fender guitar amps (?), some Conrad Johnson preamps (?)

Thanks for adding your knowledge to this thread.

 

[dewdude]

The Motorola HS-544 and HS-619 chassis both used 2 12AU7s. One in the tone circuit, the other as a driver/phase splitter. I own a pair of 619s (and have studied schematics for the *very* similar 544) and run 5963s in place of 12AU7s in it.

I think everyone liked the AX7 because of its large gain. Just a guess.

 

[kyle]

Try this:

http://lmgtfy.com/?q=12au7+preamp+schematic

 

[audiodon]

Amps unless otherwise indicated:

12AU7
HK Chorale A-260
Fisher X-1000 integrated
Fisher SA-300
Fisher 100AZ (probably 80AZ also)

12AT7
Fisher 100AZ
Fisher 500-B/800B (mpx section) receiver

 

[olds442111]

My eastern electric MiniMax preamp uses 2 12AU7 tubes, however, I roll other kinds in it as well.

 

[Sam Cogley]

This list is going to be about eight miles long.

 

[gearhound]

RH84 amplifier uses a single 12at7.


Steve

 

[Dandy]

This list is going to be about eight miles long.

+1. I'm not sure what will be proved by compiling it.

 

[olds442111]

But it will go on forever. Kind of like asking what uses an EL84 tube

 

[mech986]

This list is going to be about eight miles long.

+1. I'm not sure what will be proved by compiling it.

I understand your concerns. When you have a bunch of 12AT7 tubes and 12AU7 tubes but only 12AX7 preamps, how does one figure what other products use those tubes if you don't ask. Course, one could just say I have these tubes, what would you use them in, which is sort of the same thing, isn't it?

 

[mech986]

BTW, many Pilot amps use the 12AU7 as phase splitter?

 

[olds442111]

If theres that big of a surplus, offer them either in barter town or the audiokarma wheel. They'll go....fast

 

[GordonW]

Rogue Perseus preamp (modern production) uses four 12AU7s.

The Cary SLP98P preamp uses one pair of 12AU7s. It also uses two 12AX7s and four 6SN7s.

My modified Dyna PAS3X preamp now uses a pair of 12AU7s in the line stage (still uses 12AX7s in the phono stage).

The Heahtkit SP2 preamp uses one 12AU7 per channel... along with one 12AX7 per channel, and one EF86 per channel.

Regards,
Gordon.

 

[GordonW]

Oh- the Heathkit AA100 integrated amp comes with four 12AX7s in the preamp stage- but those can be replaced by 12AT7s. It actually sounds better, IMHO, with 12AT7s... they seem to match the loading better (they bias up to have more available output voltage 'swing', which gives the preamp section more headroom before clipping).

Regards,
Gordon.