selfsplit

[Andy Le Blanc]

Any body play around with selfsplit push-pull using larger pentodes.
I've seen quite a few low power tries for 12au7 etc.

The few text reference I've found say that the technique has a very high distortion figure.
I found a reference that it takes nearly twice the drive voltage too.

It looks very simple, a cathode biased push pull pair with the grid of one
side at ground potential.

[Bierschinken]

Hi there,

the "problem" on self-split-push-pull amps is, that you will get a certain amount of distortion by not distorting the powertubes.

Due to the signal loss on the cathode resistor (feedback), the signal on the earth connected grid is smaller than on the grid wich is connected to the former stage resulting in distortion because the tubes won´t work symetrical.

Some players like this sort of tone, some don´t like it.
Especially if you´re a higainer you wouldn´t like it cause it feels and sounds looser and softer than the usual distortion.

Cheers,
Swen

[Andy Le Blanc]

Thats a good way to put it. I've noticed with several variations of paraphrase
inverters that the clean is never clean, the tone is actually good, just not clean.
The distortion is not the same color the you expect either, its not a fender tone.

But it will work, I'd also like to try a few transformer based inverters too.
I saw a reference for an auto transformer that looked neat to try.