Originally Posted by nigelwright7557
I designed and built my own tda7294 amp with a valve front end.
I reduced the gain in the 7294 to make up for valve gain.
The amp oscillated badly. After reading the datasheet again it seems you cant have a gain below 22 or the 7294 becomes unstable.
The pcb tracks between feedback resistor and the 7294 should be as short as possible to stop inductance in the tracks delaying the feedback signal.
Lower gain is possible with dramtically reduced power voltage.
Alternatively, you could use the TDA7293 in slave mode (as a high current buffer).