On my quest to find a voltage stage for my 6a3 project I tested a 12ay7. And much to my surprise, it is very linear. Hopefully, the images attach, but at 84Vpp, the 2nd harmonics are almost 90dB below fundamental. Take the 3rds and 5ths with a grain of salt, I used my phone as the generator, and they poke out even on the baseline measurement. If I am not mistaken, Cmiller isn't crushing either at a little over 50pF. The tube tested was a Groove Tubes brand. Literally made for guitar amps. The test was performed with a hybrid mu follower, using the mu out into a 100k load. The operating point was 200Vak @1.3ma. The plan is to rc couple it to a source follower for powerdrive. Why aren't these little triodes used more?
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Nectarpuke,
I am using as many JJ 12AY7 tubes as I can.
I use them in both my single ended amplifiers, and my push pull amplifiers.
I am sorry, I can not answer your question for the rest of the designers and builders.
I am using as many JJ 12AY7 tubes as I can.
I use them in both my single ended amplifiers, and my push pull amplifiers.
I am sorry, I can not answer your question for the rest of the designers and builders.
12AY7 / 6072A has been the input valve of choice for Audio Note Kondo Japan for more than 30 years.
They can be really nice, and I used them quite a lot back in the 90s, but prices for NOS have gone crazy and nice ones have become very hard to get, so I have moved onto others.
They can be really nice, and I used them quite a lot back in the 90s, but prices for NOS have gone crazy and nice ones have become very hard to get, so I have moved onto others.
The 12AY7 is also available as new production from both Electro-Harmonix and JJ Electronic. Both brands have proven to be quality tubes in my experience (I have done some new designs with them).
As always, performance depends on the circuit design. That said, new production 12AY7 perform very very well in audio AND are robust in guitar amps.
I still use them in my new valve pre amp designs, because they are more stable and less peaky than ECC83s/12AX7s.
“Peaky”? That could be, if using multiple stages inside global feedback. There IS such a thing as too much open loop gain, especially if you can’t get the pole frequencies high enough due to other constraints.
Indeed, peakimess is more likely to be an artifact of the design not the tube itself.
Cheers
Ian
Cheers
Ian
I really like the AY7. I used it as a first stage in a guitar amp and plan on using them as a first stage in a phono pre.