Alternative Phase Inverter tubes

[Attilio]

Hi all!
Today I found an old 12AZ7 tube.
I tried to plug it into my 18W as Phase Inverter.
The first thing I've noticed was the reduction of volume: the amp becomes half loud compared to the standard 18W. With the volume you lose part of the "tone" of this amp. You get distortion only when volume pot is on 8 or 9, and only if pick strings very hard (and I have a LP, with humbuckers PU, quite powerful).
Have you evere tried other PI tubes?
I read on AX84 forum that 12AT7 is a good choice for the PI: what do you think?
Bye!

[zaphod_phil]

Hi Attilio, that was about the November, which is a completely different amplifier to the 18watter. Other dual triodes apart from the 12AX7 usually have less gain - eg the 12AZ7 has a Mu of about 60, compared with 100 for the 12AX7. This is why you lost both sound level and distortion. The 12AT7 has a similar gain, which is fine if you want a cleaner, Fender-sounding amp. It's always fun to try..!

Have you evere tried other PI tubes?
I read on AX84 forum that 12AT7 is a good choice for the PI: what do you think?
Bye!

[Attilio]

Hi Attilio, that was about the November, which is a completely different amplifier to the 18watter.

Oh, you're right! Sorry, I misunderstand that post .
Anyway you're right, it's always fun to try and experiment...
With this PI I can play at home without being killed by my neighbours !
Thanks.
Bye

[markh]

Paul Ruby has a theory that part of the 18watt "sound" is the ECC83 PI getting slammed by a very hot input signal. I think it also has to do with that PI slamming the EL84s (slam squared?). If this is correct, changing the PI to a different, lower gain tube would change the sound character. This could be good or bad, depending on what you like, but as you have observed, it will sound different.

--mark

[zaphod_phil]

And not a single mention of the EL84's driven snot...!

[Jason]

Attilio,

Check out a 5751 in the PI position. They are a pretty nice sounding tube with a mu of around 70.

Jason

[Attilio]

Attilio,

Check out a 5751 in the PI position. They are a pretty nice sounding tube with a mu of around 70.

Jason

Thank you.
I will try one if I manage to find it.
Thanks .
Bye

[whiteboyblues2001]

Just yesterday I put a Sovtek 12AX7WXT+ in the PI. The WXT+ supposedly has more gain than a normal 12AX7WA. It added a bit more distortion, but saccrificed a little warmth. Sovtek's are not my favorite brand, but these babys rock. I put another WXT+ in for V1 as well to add even more gain. It sounds great.

Has anyone else tried this tube?

Joe

[ampkits]

Hi Attilio,

Wassup? I am trying to contact you via email. Can you e-mail me at nik@ceriait.com? I tried to look for your email info here but cant seem to find it.

Thanks!

Nik