I'll list my favourites so long with some brief comments. I'm going hiking in the Kruger National Park the rest of this week. If I get eaten by a lion unfortunately I won't be able to post any further comments!
Favourites from top to bottom:
Zaerix ECC801 (Lovely clear sound with a balanced presentation top to bottom, good articulation, bass impact with a slight airiness in the treble, sounds great with the HE-500)
AEG ECC88 (Excellent sound staging (pretty holographic, easy to place instruments), lots of detail, fantastic mid range, this one was quite a surprise)
General Electric 5751, triple mica, black plate (Also nice and clear, slightly more laid back compared to the Zaerix)
Mullard 7308 (Smooth and lovely midrange, best one so far for female vocals)
Sylvania 12BH7A, black plate (Also quite clean and nicely balanced, a little bit bright at this stage, has had quite a bit a running, but mellowed less than expected)
RCA 5814R (Sounds a bit brittle, probably needs a lot more burn in time)
Amperex ECC81 (A disappointment so far)
National 6922 (The stock tube might be better than this one)
General observations: 12V tubes tend to sound cleaner on the PSii, the 6V tubes are a bit better from technical perspective, this is quite apparent with the AEG ECC88 and in the end the Zaerix takes the top honours so far.
Edited by daerron - 5/28/13 at 1:13pm