6550 to KT88

The JJ KT88's may surprise you, I guess until I get a set of the 90's I can't give you a good comparison. Buying 8 to find out I like the 88's better gets a bit expensive, although I don't know what I'm complaining about, I must have 6 sets of IC's I don't use. I need to put some of them up for sale here on Audiogon one of these days.

I have a rogue audio zues that came with the EH6550's. I was expecting the EHKT88. I was wondering if there is a big difference in sound staging and bass by going to the KT88, also which KT88 is the most well rounded? Has anyone tried the SED pearl cryo valve svkt88. The info I have read is that they are best modern production KT88. Kind of pricey for a new tube,$145.00 a pair. I have read good things about the jj KT88 and the winged 'c' KT88 from the original svetlana plant in russia. I have been thinking about trying the kt88 or KT90, but it sounds like the kt90 is going in the wrong direction. Are the electro harmonix kt88s better than the 6550s?

Be very very careful with the JJ KT88s. Their reliability was a disaster for me with them not lasting more than 6 or so months. Upon destruction, they launched a power resistor in the amp (ARC VT130) each time. I went back to 6550s, lost a little of the midrange warmth but gained a more neutral tonal balance and reliability to boot.
John

Thanks for the warning . I was considering the JJ's.

Jaq , Your concern over JJ is realistic but a maddening tradeoff because they do have the best tonal qualities of any current KT88.Both JJs I bought from a well known Canadian tube dealer went bad frying 2 different ASL amps--- expensive repairs both times.The word from a previous thread about this stated that KT88s are the most easily damaged tubes and do poorly in shipping. Try finding a vintage amp that uses 7591 power tubes. This is great tube sound.