900W H-class PA Amp with Limiter

Do anyone want to DIY something like that?
 

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NJM2068 is better than NE5532 in every way!!!

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!!!

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.
 
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.

Beg to differ...
The old guy is faster than the japanese counterpart..
ALso, it has no more distorsion , and is as much quiete..
 
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.
 
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.
Commutating diodes are SFA1603 TO-220 without heatsink, not cold but no need extra heatsink, maybie small TO-220 heatsink.
 
I will post schematics. I dont espect any interested about that kind of amplifier in DIY.
I'm not sure why not? :) I bought a Mackie M3000 to drive some bass speakers, that's a 3 stage class H i believe. When the warranty runs out it'll get rebuilt so it uses big heatsinks & no cooling fans ;)

You really don't need anything super quality when used at less than 100Hz in reality, 0.1% distortion should be more than adequate :)
 
I will post schematics. I dont espect any interested about that kind of amplifier in DIY.

actually, i do. i love high power amps, repair almost only pa stuff or heavy hifi and love to learn more.
reading and understandig schematics is a great way of practical learning

could you post an etch-able pcb layout too?

is it really 900W @ 8? i'd guess at 4 ohms or less with only 4 pairs of 1943/5200..
 
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actually, i do. i love high power amps, repair almost only pa stuff or heavy hifi and love to learn more.
reading and understandig schematics is a great way of practical learning

could you post an etch-able pcb layout too?

is it really 900W @ 8? i'd guess at 4 ohms or less with only 4 pairs of 1943/5200..
Power suply 0,+/-60V,+/-120V. THD 0,03% 20-20000Hz on 900W 4 ohms. All new brand amplifier use 4 pairs of 1943/5200 evan for 1900W 2 ohms in their specification. I dont want to go tnat much.