I pretty much have all the bits needed to make this, including the power supplies and heatsinks (from a dead solar inverter).
Suggestions welcome.
Suggestions welcome.
Should work well.......
Big issue will be finding the correct operating point for the first triode.
You may find with only small current through it the sound might sound a little twee. You have latitude; increase current to say 8.5mA you can use a plate load of 18k, this will put plate voltage at half B+ and it should sound strong.
Haven't seen IGBTs used as audio outputs, but it should be OK and easy to drive.
No fb so no stability issues, and it should sound very natural.
Big issue will be finding the correct operating point for the first triode.
You may find with only small current through it the sound might sound a little twee. You have latitude; increase current to say 8.5mA you can use a plate load of 18k, this will put plate voltage at half B+ and it should sound strong.
Haven't seen IGBTs used as audio outputs, but it should be OK and easy to drive.
No fb so no stability issues, and it should sound very natural.
Hmm, 8.1mA current with an 18k resistor. THD quite a bit worse, but then it does show monotonic decrease with increasing harmonics, unlike the 68k where H3 > H2 at higher input voltages.
Thanks. It's worth making that resistor easy to swap.
Thanks. It's worth making that resistor easy to swap.
Don't be concerned about THD with a tube. 99% of that THD will be the first three harmonics, H2, H3 and H4, all musical.