MPP

I took away the 100pF at the gates of the MosFets and, voila !, it is working.
The MosFets do not like the 100pF NPO´s.
At the sweetspot of my QA400 i measure -110dB with a nice spectrum.
Most second and then 3rd, 4th and so on exponential decaying.
Under 300mV only the second at -110dB is left.
This is still the version with the lower impedance voltage devider and 270 ohm gate stopper of the BJT version.
It is also the starved version with low idle.
Raising the impedance in the bias devider and ramping up the idle i expect even better performance but it already works fine.
 
How much distortion can we hear ?
The text shows that we should take masking into acount but it does not come up with numbers :Golden Ears Columns - Distortion and the Data
Therefore i still design for as low distortion as possible.
It simply feels more satisfying when a circuit is maxed out.
That does not cost aditional money but aditional work.
Time is money though.
 
here....
 

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