As an interesting Saturday evening experiment, I pulled the 6L6WGCS out of the Chubby Clementine, and put in a matched pair of "golden S" Svetlana EL34s, and the sound is noticeably nicer than with the great sounding Russki 6L6WGCs. It also delivers about 50% more output power with lower 2HD and 3HD. These toobs have 1.6 amp filaments, vs the 6L6s' 900 mA, and the B+ current for each EL34 is 67 mA each vs 58 mA for each of the 6L6s, so I am running the power tranny at the "edge of the envelope" as far as the 6.3VAC @ 3A and the 120 mA B+ current rating (136 mA vs 118 mA). A PA-774 should be able to handle the extra curernt demands with ease, as it can deliver 5A 0f 6.3V and 180 mA of B+.
After a couple hours operation, I can still put my hand on the power transformer, for about 30 seconds without feeling any thermal induced pain or raising any blisters (try that with an ST35 sometime)
I did not change any resistor values, they are all original for the 6L6GC design.
The tranny ran only "warm to the touch" under the 6L6s and 6SL7 loading, but I will monitor the tranny's temperature during extensive testing. The tranny is a one-off prototype, and I suspect that it was conservatively designed and rated.
I ran a SE-CAD simulation, the 6L6WGC has a mu of 7.5, rP of 1.7K, gm of 4.43 mA/V, IK of 58 mA, PO = 2.46W @ 6.2% 2HD and 0.4% 3HD.
The EL34 has a mu of 7.12, rP of 1.07K, gm of 6.67 mA/V, IK = 67.2 mA, PO = 3.60W 2HD = 4.7 mA, 3HD = 0.2%.
/ed B