Floating supply amplifier (backward, transnova, qsc)

[UltimateX86]

Hello,

I'm interested in floating supply power amps like Transnova Hafler, QSC, Acoustat, Dalix, and I just found these diagrams on my hard drive.

I do not know where I copied these pictures, I search for their provenance.

I searched on google, on this forum but nothing.

I like the use of op amp directly on MOSFET

Thanks
Best regard
Sébastien

 

[UltimateX86]

HI,


I simulated this diagram in LTspice... it's a nice oscillator

 

[UltimateX86]

I tried another solution...

 

[UltimateX86]

the mirror version increases the quiescent current with the temperature, the other decreases, it may be better

 

[stoneku]

This is a AD811 CurrentFeedback OPAmp TRANSNOVA topology 250w/8R power amp simulation.
Main amp use AD811 , with TL082 as balance-to-unbalance input buffer and dc-servo .
The AD811 can alter use AD815 CFA will get same good performace, but if alter use AD823 or TL082 will increase much more THD.