how about this output stage ?


i dont want to design ops driven from the one side (up or down)
i want audio injection like here.

i am not using double (symetric) bootstrap because i think its possible to make amplifier more prone to oscillation ?

Or it makes oscillation but these capacitors shorten out it ? C1,C2,C3,C4


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Ahh it was a mistake, i was reversed transistor pins.
it was BCE now is ECB for those packages :D

It sounds veery goood :p :drink: :Popworm: :darkside: :Piano: :scratch1: :emoticon: :wiz: :wiz: :masked:

losing my time :rofl::wchair::irked:

No heat at all with big speaker but i cant get high volume, i dont know why.

P.S. Transistor failed when i pushed the low freq eq high and the bass kicked in :(
Heatsink cold but maybe these transisors are small and there are peak currents
Maybe they are useful for bi-amping for mid and high frequency
Last edited:


Paid Member
2007-09-15 8:14 am

Just a reminder to play by the rules here. No one is under any obligation to contribute to the thread... and mosfet, you might do better to try and listen to all the advice that is being given and try and see one thread through to a meaningful conclusion rather than keep starting new ones.