Rleff thanks for your follow up and interest
The technician removed the bottom cover and to my surprise the manual bias adjustment is for both EL34 and 6SN7 tubes. There is no bias adjustment for the 12AX7 tubes. The manual biasing is fairly simple as described in the initial response from Depotec above.
While he was inside he put in better capacitors and per the technician even prior to the expected 100 hours of burn in the improvement made has been significant, with more improvement expected as the caps continue to be burned in. He still has the component and I intend to visit and listen with him this Sunday. We are considering adding bybee quantum purifiers, WBT silver connectors for the RCA interconnects and better but not as expensive as the WBT binding post, probably copper binding posts by either Cardas or Eichmann. The good news is so far all the work done has been at a reasonable price.
Cityboy
