John- That's interesting to hear the Phi Beta vs Sigma comparison. Speaking with Kevin, he has the latter as his home amp these days. I figure it sounds a bit more "SS' like than the Phi as I tried a Phi 200 and it sounded pretty much like my Mac SS gear.
For tubes, I preferred Shuguang Treasures for KT88s and Psvane 12ax7s. I didn't really like the stock Vac tubes at all like some say- ymmv. I didn't have time to roll 6SN7s as much, but some RCA red bases were pretty awful sounding in it. In general, I found the amp a hair rolled off, so you want to pick tubes that won't be sweeter/mid-rangier. I now have a set of 50s Sylvanias 6SN7s that I'm sure would be perfect for the amp (that I used for a preamp recently).
Yes, soundstaging and dynamics are the amps hallmarks- it will take you a bit to get the tube combo right, but enjoy it in good health!
KeithR
For tubes, I preferred Shuguang Treasures for KT88s and Psvane 12ax7s. I didn't really like the stock Vac tubes at all like some say- ymmv. I didn't have time to roll 6SN7s as much, but some RCA red bases were pretty awful sounding in it. In general, I found the amp a hair rolled off, so you want to pick tubes that won't be sweeter/mid-rangier. I now have a set of 50s Sylvanias 6SN7s that I'm sure would be perfect for the amp (that I used for a preamp recently).
Yes, soundstaging and dynamics are the amps hallmarks- it will take you a bit to get the tube combo right, but enjoy it in good health!
KeithR
