5-6W at 120V B+ needs rare or custom ~ 500 Ohm SE OT with 200 mA DC bias. I would suggest an easier to obtain 2K5 PSE OT rated for 100mA bias and raise B+ to 250V.
You can use the attached schematic a a starting point if you know what you are doing. Current production Diodes SOT223 input PMOS and Wolfspeed C2M100170D, can be adapted to Rohm SCT2450. 6.55W @ 2V rms input, K2 dominant Neg phase, DF ~ 3.85. Requires 1K/W HS or better per channel. VR1 sets bias, monitor at R1. Increase R1 (up to 6.8 R) if bias can not stabilize at operating temperature.
Please start a new thread if you have questions or need more help since this is OT.
Attachments
Just for fun while I'm working up the other stuff, here's a true junk box quickie:
.4% THD @ .5W 8 OHMS
Clips around 3/4 of a watt
Balance a couple for two massive watts
No adjustments
Can use a small TO-220 heat sink
Nice warm glow
could this work with irf710 and reversing the PSU polarity of course?!
Not that it matters now, but some time ago I had this fantasy of designing a power amp with parts available from Radio Shack. Idea was that anyone could walk into a national chain store and buy parts to make a power amp. They had a IFP510 or IRF610 and a bunch of different BJTs. Never thought anyone would care about an amp with 1 watt. This thread is proof I was wrong again.
Anyway, had that thought rolling around my head for a long time. Needed to let it out.
Anyway, had that thought rolling around my head for a long time. Needed to let it out.
It works, but in this particular case the bigger parts yield lower distortion.
I will parallel some irf710 as I have many, it will increase yfs and decrease distortion?