hi..i have some questions for experts..please dont answer if you are not an expert 
1-how we decide the max or best voltage supply value of single ended symmetrical class a amps?(for this amp with irfp240 transistors)
2-i replaced irfp240 instead of irfp 150 in this circuit.mids and trebles increased and bass reduced..but i always see positive offset of 150mv..i can reduce it to 100mv only by playing trimpots..i can not reduce it anymore..which values of resistors should i change?
3-what is the technical criterias of sound quality for transistors?
is it low input capacitance?or low Qg?
thanks
best regards
umit
1-how we decide the max or best voltage supply value of single ended symmetrical class a amps?(for this amp with irfp240 transistors)
2-i replaced irfp240 instead of irfp 150 in this circuit.mids and trebles increased and bass reduced..but i always see positive offset of 150mv..i can reduce it to 100mv only by playing trimpots..i can not reduce it anymore..which values of resistors should i change?
3-what is the technical criterias of sound quality for transistors?
is it low input capacitance?or low Qg?
thanks
best regards
umit
