In my opinion it is always a good idea to use sockets, especially for jfets. For some circuits you'll find out things can change dramatically when testing different ones. I tried a bunch when built this but I don't recall any buzzing.
I replaced the 10k Drain bias' with trimmers and both JFETS at 4.5v yielded the best results.
I have soapbar/humbucker pickups on my bass and they were too hot a signal, so I got a lot of distortion out of this thing, even after adjusting bias trimmers.