Power tubes for SF Power 2?

Anybody have an opinion on the best sounding output tubes for the Power 2. I just picked one up with re-issue Tung Sol 6550s. Are KT-88s the way to go?

Ozzy, FWIW, I assume you have the SF manual and know what tubes are recommended for this amp by SF, however if not, don't make any assumptions. I have both the SFS80 and SFM's 160's. KT88 sound and work fine in the SFS80 so I mistakenly put them into the 160's. Poof! Then I read the manual - it recommended KT90's and 6550's and recommended against the KT88's is being incompatible.

If the sound in the SF P2 changes as it did in the SFS 80 - the 6550's (SED's) provided a very even tone from solid bass thru the highs but was a bit coolish. In comparison SED KT88's warmed up the lower-midrange and gave a bit of sparkle and air in the upper mids/highs. Personally I preferred the KT88 in this amp.
I am pretty sure I read that KT-88s are possible. I will check again. KT-88s usually have more power and improved bass response, but don't have the natural tone of other tubes. But that is not always the case. If what you hear holds true for the Power 2 also, it sounds like the KT-88s would be more to my liking too.

I have a Power 2 and use KT88s in it. I asked Chris at PartsConnexion (The orginal designer for Sonic Frontiers) he recommended the KT88s over the 6550s
CHris is now recommending the reissue tungsol 6550s over the KT-88 tubes

Happy Listening