Hi glt, in theory this seems good, which is one reason I was confident using the JFET, but if you look at the datasheet you will notice the static drain source impedance(100ohms) comes into play more than you might think. But this impedance can change from part to part. I am rethinking this a bit now and will change things a bit in the next revision.

In any case, most people will never see this phenomenon. The only reason in this case (not all) IVY is effected is because of the way the opa1632 folded cascode front end work and tracks VOCM. The "thump" will be common mode, and as such not effect balanced gear.

Anyway I am very glad spresto9 spoke up and asked for help, otherwise I would never have guessed this could occur. It took 2 days of head pounding,simulating and testing (not necessarily in that order) to figure it out.

I am also very glad my fix worked for him and he can stop worrying and just listen to the music now. :)

Cheers!
Russ