Thanks, slider313! I agree with your evaluation of the JJ's. I've already ordered a GE 5U4GB, and I'll re-bias it when I get it back from my tech next week. I've got a matched pair of Tung-Sol black glass 6V6GT's that I'd like to try in there. I loved them in my DRRI. It seems to me that the previous owner was trying to make the SFDR sound a bit more like a Twin by using those JJ's, which are kind of like a little 6L6, a GZ34 rectifier, and biasing to about 60% mpd, so it's not too warm. Very clear and linear sounding. Also they used the WGS equivalent of an EV SRO, the WGS Blackhawk HP alnico. I'd like your opinion on something. That WGS Blackhawk HP sounds fantastic, but what worries me a little bit is the bass response. It's enormous, and the speaker is also heavy. I play in a "live room" with wooden floors, and a 9 lb speaker on that medium density fiberboard baffle concerns me a little bit. The baffle is not in perfect shape. The question is this: If I swap out the speaker in this SFDR down the road, I'd like to know what you would put in it. If it were yours, what speaker would you use (aside from the OEM)?