900W H-class PA Amp with Limiter
 

Do anyone want to DIY something like that?

hi apexaudio
greetings cool pcb would be a great diy project for h class diyers
keep up the goodwork
thanking you
andrew lebon

On this PCB I use IRF540 in paralel for step higher voltage, and LDR for limiter. Output stage with 2SA1943/2SC5200. Step driver with IR2117 and NE5532 on balanced input stage.

NJM2068 is better than NE5532 in every way!!!
 

NJM2068 is better than NE5532 in every way!!!

To everyone- please quit using this horrid sounding 30 year old op amp. The 2068 is better in every way, quieter, lower distortion, less offset and drift, larger output current, lower input bias, faster, and most important of all it sounds FAR better than any 5532 ever thought about.

This is 10years old schematics. Can be upgrade with new OP amp.

Beg to differ...
The old guy is faster than the japanese counterpart..
ALso, it has no more distorsion , and is as much quiete..

I suggest you measure these two op amps in circuits as used and see the result.

I used TL072 on some PCB, at the end this is PA amplifier, work with 18inch subwoofer.

It doesn't look like your commutating diodes are on the heat sink.... Are you expecting them to run stone cold? I wouldn't. BTW - which ones are you using? Looks to me like a 2-lead TO-220.

BTW - for all the naysayers - there's nothing wrong with a 5532 in a PA AMP! I use OPA2604's but that's personal preference because I grew up on the LF353. Still doesn't pass the audiophile snob test.

Well lets just say that seeing how it is built would be interesting :) I'm sure that a good few people could find use for a powerful & more efficient (than AB) amplifier :D

I for one am interested & thanks for sharing if you do ;)