Just to stir the waters a little: Kevin has a new phono stage design that is ready for roll out in beta form. Fully differential, 3 stage, series feed (current kit is parallel feed) design with cascode CCSs at the "tail" of each stage and a separate cascode CCSs to feed a filter cap and shunt resistor to supply the B+ for each stage. Both the plate and the cathode sides of the tubes are isolated from the PS by high impedence current sources. Series feed means no parafeed caps to color the sound. Only caps in signal path are RIAA filter caps. I have built Kevin's fully differentail parallel 6550 mono-blocks with a similar circuit topology to this and can say they are very quick, dynamic and transparent amps. Expect new phono pre to be also. Downside? 2) LL1931s and FOUR amorphous core ITs mean it will not be cheap! I expect to get my hands on one in the next few weeks. I will post a follow-up.
