I've always used NOS tubes, but when I wanted to replace the eight matched 6550s in my Cary mono-blocks, I almost went apoplectic! The prices have gone nuts on matched quads/octets of anything worth having(supply and demand strikes again). To my surprise and delight, The Winged "C" 6550's(St Petersburg plant) actually out-performed the Phillips octet that they replaced(more open and transparent). I wouldn't purchase output tubes from anyone but Upscale Audio. Their screening, and matching processes can't be beat! Kevin is anal about his quality control, and company's reputation(and I like that a lot). I have no other connection to them, other than as a very satisfied customer. Check out the test equipment/process descriptions he includes on his site:(http://www.upscaleaudio.com/product.asp?itemid=16&catid=85) Ask Kevin about KT88s in your application. You may be able to get a bit more output with them than with 6550s. Kevin will be able to advise you as to any differences in sonics between the two. Happy listening!!
best output tubes for jolida 502b
I just purchased a jolida 502b. This will be my second tube amp. I bought a sophia electric baby but it didnt go loud enough,(I like to rock out sometimes). Anyway the output tubes I got with the 502 are the stock ones and they have some hrs on them. Does anyone have any advice on what tube to use when I replace them.