Simple Symetrical Amplifier

[naf]

Dear Shaan/LazyCat
I ask your permission to upload your ssa schema/ board and of course my build to my local diy forum.
Please i need your answer yes or no.

Regards
Naf

[shaan]

Why not, also post a link to this thread too in your local forum.

[naf]

Originally Posted by shaan

Why not, also post a link to this thread too in your local forum.

Thank you Shaan, i'll post link to this thread of course.

[Nico Ras]

Originally Posted by shaan

That's right Christophe. Class-D is actually better in this respect, but I doubt any Class-D can do what SSA can, sonically speaking.

If I am on the right track, we definitely need a Class-H SSA.

At 1 kW I do not think anybody cares what it sounds like. If you are too close it is too loud, if you are too far then you cannot hear detail anyway.

[shaan]

[coolewater]

Hello , sorry for my bad english,

with great interest that I have followed this thread. At Home, i have many solid state Power Amplifier. Among others I have Sansui AU919, LC-Audio without feedbag, accuphase clone, Marantz clone with current feedbag. Best sounds the marantz amplifier, with current feedbag. For this reason I want to build an ssa mosfet amplifier. My question: how do I calculate the voltage of the Z-Diodes D3 and D4? Are 10 volts sufficient? With this configuration, i have a current of 14 mA to the cascode Q5 Q11.

Thanks and regards Gerd

[Lazy Cat]

Hi coolewater

Welcome to SSA thread.

It's not about zener voltage, it can be any value higher than feedback voltage drop on 100 ohm to GND resistors. In your case 5,6 V or higher. Important here are the values of current injected resistors R8, R10, who as the name says, inject current to the input stage and to 100 ohm to GND. In your case that sum would be app. 2,5 mA. You can change R8, R10 with CCS any time later, for the start it's just fine.
Since you'll operate with quite high supply voltages, heat dissipation on certain parts will be higher than normal, so good heatsinking required here is necessity.

Regards Andrej

[coolewater]

Thank you :cheers

I bought for little money a broken Crescendo amp. The two transformers are from the Crescendo amp. Each Transformer has 2* 24 Volt AC, 340VA. From china i have bought a big case with heatsinks. Also i have a goldmund telos clone. I want to compare the ssa amp with the crescendo and the Golmund amp. If the SSA the better amp, i will replace one of the transformers, to a transformer with less voltage. I know I'm crazy :smilie

Gerd

[shaan]

Hi LC.
In a much earlier post you said it's gonna be better than Goldmund. What is your realization so far?
Thanks.

[Esperado]

All along the numerous pages of this thread, near everything has been said to demonstrate the advantages of CFB vs VFB topology, on a musical point of view.
But one.
The coherency between small signals and large signals reproduction.
Looking at square waves as well at the frequency response curves, it is obvious.
And no VFB amp i know can reach that point.
I suppose it is significant in regard to the easy, coherent and fluid dynamic that offer SSA .