SE J/MOSFET Class A Amp, no Feedback

widowmaker · 8th July 2007, 10:51 PM

Here is my last project of two stages (common source & source follower) class A amp.
AgTa caps are K52-2, russian military production.
Amp was specially made for bulgarian fullrange driver Ether.

AKSA · 8th July 2007, 11:28 PM

Daniel,

Nice circuit, nothing too unexpected.....

Could you describe the sound? Tubelike would describe it?

You have the usual Vgs distortion of the SE source follower.

Could I suggest something? A simple emitter follower regulator with heavily decoupled zener for reference on the input stages rather than the chip; in my experience it sounds better, more vitality....

Cheers,

Hugh

widowmaker · 9th July 2007, 12:41 AM

Quote:

Originally posted by AKSA

...Could I suggest something? A simple emitter follower regulator with heavily decoupled zener for reference on the input stages rather than the chip; in my experience it sounds better, more vitality....

Cheers,

Hugh

Of course, trans is better solution

Yesterday, when I made the prototype, I had only two 20V zeners on hand

Sound is deep and very fast with tight bass and bright mid and high freqs.

Output power is 17-18 watts (there is a mistake in attachment).
Signal (top) 1529 has current regime between 0.5 and 6.5A for full power(Imin and Imax) and dissipates 52-53 watts.

Gordy · 11th July 2007, 02:52 PM

I have seen other circuits from you, and they are always interesting. Good luck.

8th July 2007, 11:28 PM	#2
AKSA diyAudio Member Join Date: Sep 2001 Location: Melbourne, Australia	Daniel, Nice circuit, nothing too unexpected..... Could you describe the sound? Tubelike would describe it? You have the usual Vgs distortion of the SE source follower. Could I suggest something? A simple emitter follower regulator with heavily decoupled zener for reference on the input stages rather than the chip; in my experience it sounds better, more vitality.... Cheers, Hugh __________________ Aspen Amplifiers P/L (Australia) www.aksaonline.com

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11th July 2007, 02:52 PM	#4
Gordy diyAudio Member Join Date: Nov 2006	I have seen other circuits from you, and they are always interesting. Good luck.