QUASI Amplifier for Beginners

Better still, if Yehan cannot design, then he should not be modifying an existing design.
It seems to me that the best Yehan can achieve is to copy exactly an existing known and recommended design and build without any changes that may compromise the performance.
 
Oops!… I Did It Again

I built the amplifier with two pairs of transistors and it works with +-40V DC. The Sound ist great.

Thanks apex, very nice for beginners (like me ;-)

Olaf
 

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I built the amplifier with two pairs of transistors and it works with +-40V DC. The Sound ist great.

Thanks apex, very nice for beginners (like me ;-)

Olaf
Hi olafk!
According to this schematic, where you worked?😕
Since the standard schematic error is ( take a look topic?!)
Such should be!!!
Cheers!😉
 

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hi Apex sir,
Currently using this amp with 5 pairs of 2n3773,supply 40-0-40 AC 1.5kv traffo,20,000mfd caps per side on 4 ohm load. sounds good to my ears even as full range amp but currently coupled with your 2x12 inch subwoofer enclosure in a three way system.
What output power i should expect from this ?
 
Very hot

Hi,

I built the amplifier (picture see post #663) with two pairs of 2N3773 and I use +-60V DC. Now the Transistors MJE350/340 become to hot. I can touch them for only 3-4 seconds and I think it is a bit critical.
Should I reduce the voltage (have regulated power supply) or are there any other things I can do? I changed the heatsink to a bigger version for TO220 like the MJE15030, but gave no better result.
Can anybody help me?

regards
Olaf
 
Hi,

I built the amplifier (picture see post #663) with two pairs of 2N3773 and I use +-60V DC. Now the Transistors MJE350/340 become to hot. I can touch them for only 3-4 seconds and I think it is a bit critical.
Should I reduce the voltage (have regulated power supply) or are there any other things I can do? I changed the heatsink to a bigger version for TO220 like the MJE15030, but gave no better result.
Can anybody help me?

regards
Olaf

Nice work, MJE340/350 work in class A and must be hot but use 100R resistor instead 56R around MJE340 and this will reduce current in VAS CCS and disipation on MJE340/350 also.
Can you share your pcb?
Regards
 
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