Doing a littlee messing around with my Bias Rite today. A while back I had picked up a Sovtek 5Y3 for my SDG Vintage Tweed Proluxe (w/6L6's). The NOS Tung Sol that came with it was acting up a little and I just picked up a cheapo for the moment. The other day I picked up a NOS Sylvania from Jeff Andrews. Anyway I had commented to Jeff that the Sovtek Sounded like a Solid State Rectifier to me and now I think I see why. Just in going from the Sovtek to the Sylvania there was a 20 ma drop or so. It seems to me the New Production Sovtek is hot as a firecracker and the NOS rectifiers are much more reserved. Whats the reason for this? Different design? New Production? I had noticed the major difference in going from the Tung Sol to the Sovtek and a very similar difference between it and the Syvania.