KT88 Opinions

I'd been using Phillips 6550's in my Cary SLM-100's for a few years and thought they were getting a little weak. The prices of NOS anything(let alone matched quads/octets of anything NOS) nearly left me apoplectic! I tried an octet of EH KT88's(cryo'd), and couldn't get them out of there fast enough(they sold pretty quick on eBay, thankfully). Then I contacted Kevin at Upscale Audio, and he recommended the latest Winged "C" 6550's from the ST Petersburg plant. I was very pleasantly surprised that a newly manufactured tube could perform as well(transparent, dynamic, liquid, extended) as the NOS tubes I'm accustomed to. If you're not familiar with his testing/matching/burn-in procedures, check them out here: (http://www.upscaleaudio.com/product.asp?itemid=16&catid=85) I have no connection to his company, outside of being a very happy customer.

Ducati - Talk to the guys at Doug's Tubes. I went from stock Sovtek 6550s to JJ/Tesla KT88s and more recently to Shuguang solid plate KT88s. Both mftrs. KT88s were better sonically than the Sovteks in several ways. Howevere, the Sovteks were ~5 yrs old or so and I'm guessing not even in the league of your Phillips 6550 to start. I really, really liked the JJ/Teslas but they were not too reliable. Compared to the JJ/Teslas, the Shuguangs seem more detailed, with more hi end extension and air. Downside is a bit of harshness on some CDs(but not vinyl) when listening at louder volumes. Good luck with your decision.

Agree with above..Doug's tubes. The Shuguang Kt-88 solid plate( not plate with holes) is very good as are the JJ's..different, but good.. Both better the Sovtek, EH, and Svetlana tubes. I prefer the SED Winged =C= myself.