tremolo circuit in 6g5 vs 6g5-a

[burt_toast]

anyone here actually know the "sound" difference of these two designs?
i guess the 6g5 used 2 tubes, and the next model out, the 6g5-a used 2 1/2 tubes.

i'm thinking of doing this in my own amp, but as it sits, could only accommodate the 2-tube version (without punching/adding a socket). i freakin' love that harmonic tremolo sound! would like to try this.

thanks

[HotBluePlates]

anyone here actually know the "sound" difference of these two designs?
i guess the 6g5 used 2 tubes, and the next model out, the 6g5-a used 2 1/2 tubes.

No, I don't. I heard a brown Concert once, but don't know if it was the 2 or 2-1/2 tube version.

From a tech standpoint, the 2-tube version looks like a paraphase inverter approach to getting push-pull signals for the trem, while the 2-1/2 tube approach uses a cathode follower then a split-load inverter to get push-pull trem signals.

The purpose was to have a way to modulate the guitar signal, then eliminate the oscillator signal at the vibrato output to get the effect without pumping.

I'm guessing Fender found the paraphase approach to be imperfect at avoiding pumping and switched to the 2-1/2 tube version to solve the problem.

[burt_toast]

thanks, HBP

yeah, my guess is (and i haven't sat down with either amp) for Leo to ADD a tube (and $), the 6G5-A must sound better/be more stable.

the amp i wanna try this with is my old BF bandmaster, which has been more jcm800-like for 20+ yrs - now more like a 5E5 Pro w/el34s. if i un-parallel my first stage, i'll have 2 1/2 sockets free.

the sad irony here is, of course, i removed the original vibrato years ago (rape/pillage), only to cram a different one in now - ah youth...

thanks