Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => Tubes and Hybrids => Topic started by: jfetter on November 15, 2018, 07:52:42 PM

Title: Hybrid valve and TPA311x
Post by: jfetter on November 15, 2018, 07:52:42 PM
Two years have tested others and this one sounds the best.
I built it point to point but now doing a board.
The tone tilt I think beats all others. Shown here in hifi mode but easy to add scoop.
Uses 12AU7 and $3.00 D class module.

Schematic attached. The fx loop is not fully tested.
Cheers


Title: Re: Hybrid valve and TPA311x
Post by: jfetter on September 13, 2019, 03:29:50 PM
A reliable pcb pot (ie Beckman ) cost quite a lot. So I put a servo-buffer opamp and configured as a ' super triode' . It took a long time to get it right...
This plot is using a sa5532 with 6sn7 in feedback loop.

It's raw right now in fact going to a lower gain tube but the plot shows 1khz signal , 2 khz dominant harmonic , 4th etc.
Third and fifth very low.