Which tubes to roll

no idea who is selling them, but in general, e-bay is a crap shoot for tubes.

If replacing the KT-88s,I would suggest the Gold Lion or Shuguang KT88-98.I have never cared for russian tubes.
You might consult Vintage Tube Services/Andy Bauman on the input tubes-very knowledgeable.

On every tube amp I've ever had the input tubes made more difference in tone than the power tubes.

If that amp is tube rectified you can also roll that for different presentation. A rectifier thats higher voltage will bias the amp towards a more agressive sound, lower voltage more relaxed.

You can run 6550C's, 6L6, or EL34 as power tubes instead of KT88's in that amp.

After you change tubes you should let them warm up, and reset the bias(140ma) as per the manual. When I swap tubes I first set the bias low with the old tubes, swap tubes, then once warm bring the bias up to spec. The eliminates the chance of being over bias on different type tubes.

John C.

For whatever power tubes you decide on: Upscale Audio's quality and customer service are hard to beat. Check out Kevin's procedures and offerings: (http://www.upscaleaudio.com/view_category.asp?cat=85) Both power and driver tubes have a major impact on your presentation. Try some NOS 6SN7GT/VT-231 (Sylvania or Ken-Rad)bottom getters from the 40's for a real treat: (http://shop.ebay.com/?_from=R40&_trksid=m38&_nkw=vt-231&_sacat=See-All-Categories) Neither are expensive right now, and both provide an expansive sound stage, excellent imaging, accurate timbre and frequency response. Here are some comments on what to expect with some of the different brands available: (http://home.att.net/~chimeraone/6sn7sound.html) I've purchased quite a few tubes on the "Bay" over the past few years, and only had one bad experience.

I agree with Rodman, Kevin is a very knowledgable guy and stands behind whatever he sells. He also has the SED KT88's that you mentioned and for the same price.