My MOSFET amplifier designed for music

Hi Mooly.
Sorry for the type of query. In many treaties has said that the quasi setting sounds better than symmetrical. You are not investigated this setting on your amp? Thanks.
 

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Hi and thanks for the interest. I haven't tried a quasi output stage, but you are correct, they have a very good reputation in some circles for sonics. Why don't you try it :)

Also perhaps try with an NPN driver for the upper MOSFET as the current through the CCS Q3 is only around 6ma.
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The design as presented is fully worked and tested and owes a lot to the use of the single ended input stage for its sonic qualities.
 
Hi Mooly,
nice job.
However, with R17, R22 1k5, it is impossible to have 'heavily bias class AB' Isn't it ?
Why don't you reduce the R17,R22 to just several ohm, for instance 82ohm? You can run with 250mA bias on the mosfet or even 700mA but with decreasing the supply rail to 24-30V (max).
You can feel the different sounding with higher/heavily
 
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Thanks for the kind words didik.

The design evolved to its final form both after much listening and also testing. The case and construction method using the "cans + heatsinks" put a limit on what was possible dissipation wise but the design works (sounds) really good as it is.

thanks for the interest :)
 

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Hi Mooly, yes I agreed with you, trust 'our own ears' .
Sorry, it was a mistake, I meant with the R17, R22 1K5, it is not pretty sure that the driver will run at its sweet spot caused by possibly too low of Q current. The mosfets of course can run hot even in pure class A but not for the driver. Please correct me if I am wrong.
With this current conditions, your amplifier has sounded very good but you can probably make it sounds much better. :)
I designed JFET-MOSFET amplifier based on GoldMund Mimesis3 but with some changes according to my taste. I will upload it later.
 
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