They were indeed 12AX7LPS's. This amp is the 5150 combo and obviously the tubes got worse sounding with more play due to the tremendous vibration, but they never sounded good from the get-go. I got the JJ's at Eurotubes. I don't remember which one was "voiced" a little different, but just popping that one tube in place of the Sovtek was like night and day. I just replaced all 5 12AX7LPS's with the JJ's as well as the Sovtek power tubes for JJ's. It would be interesting to hear some NOS Tung-Sols in the power section.