A75 to BA2?

[Botte]

I’m looking at changing my A75 to a BA2 and am looking for opinions.

My A75 works fine but I’m much happier with the F5's i made last winter. I think that the Jfets in the F5s offer sonic improvements over the mosfet inputs on the A75. One option would be to change the inputs to the A75 to Jfets and cascode them to handle the higher voltage. Or rework the Amp into a BA2.

The Issues I see with the BA2 conversion are;

Higher voltage supplies (I could cascode the jfets on the BA2 or cut the supply voltage in half (~22V for the output and say 30V for the input))

The A75 has 12 pairs of outputs (remove every other one) I’m thinking the BA2 could have trouble driving that much capacitance.

What am I missing?

Thanks,

[Nelson Pass]

You aren't missing anything. You can do all that, and you'll
notice that the BA1 version of the front end is driving
considerable capacitance already. Just let it drive the
bigger output stage instead and don't worry.