by EdwardSMaTeresa2 » Fri Apr 29, 2022 7:18 am
I think you should move C2 between the drain of J2/J3 and R9 (I presume R8 just models the mixer--otherwise you could skip it). Otherwise sufficiently negative voltage swing will turn on D4. R2 is not needed then, and R10/R12 could be made about 10x lower which should bring HF distortion down a bit. Also between C7 and V+ there should be a resistor to define the time constant.
I don't think a shunt switch will work particularly well here. To make it effective we a need significant source impedance, which is no what we want here.