OK so I took measurements with KT66 (Gold Lion reissues) and 6V6 (RCA Blackplates). First just let me say this amp with the 6V6 tubes, OD engaged and master around 2 o'clock sounded amazing (will try to make some soundclips when I get a chance).
With the numbers below, the K refers to KT66 installed, V refers to 6V6 installed, and the parentheses refers to the numbers in the table on p52 of the manual (or layout diagram as noted). All readings taken after 10min of idle. Readings taken within about 30min of swapping tubes. Overall the numbers look good except for low HVAC and B+ and V5/6 Pin 3 and 4. V1-4 are almost spot-on. The only other value that sticks out is V4 Pin 6. Amp is sounding good, all controls operational and its pretty quiet.
Wall voltage (VAC): K117.1, V117.9 (122) Heaters(VAC): K6.18, V6.33 (on standby) HVAC: K665.4, V686.1 (no reference) B+: K430, V427.4 (442)...note: for 6V6 setting, B+ was 432.2VDC prior to Zener Bias: K = 34.7 and 34.1mA; V = 18.4 and 16.4mA
V5 and V6 (values within 1 VDC on each tube, so reported just once) Pin 3: K428.6, V426.5 (441 per layout) Pin 4: K 402.2, V400.0 (411 per layout) Pin 5: K-48.2, V-39.7 (-39 per layout)
V1 (Mullard Reissue 12AX7) Pin 1: K150.4, V146.7 (150) Pin 2: K0, V0 (0) Pin 3: K1.1, V1.1 (1.2) Pin 6: K133.1, V129 (120) Pin 7: K0, V0 (0) Pin 8: K0.9, V0.9 (1)
V2 (JJ 12AX7LPS) Pin 1: K182.5, V178.2 (179) Pin 2: K0, V0 (0) Pin 3: K1.1, V1.1 (1.2) Pin 6: K106.2, V102 (106) Pin 7: K0, V0 (0) Pin 8: K0.7, V0.7 (0.7)
V3 (Mullard Reissue 12AX7) Pin 1: K264.3, V260.7 (269) Pin 2: K65.7, V64.4 (67) Pin 3: K69.3, V68.3 (71) Pin 6: K183.7, V180.8 (188) Pin 7: K0, V0 (0) Pin 8: K1.5, V1.5 (1.5)
V4 (NOS Mullard military 12AT7) Pin 1: K267, V266 (274) Pin 2: K69.4, V68.4 (71) Pin 3: K72.7, V71.7 (74) Pin 6: K262, V263 (236) Pin 7: K63.3, V62.4 (64.4) Pin 8: K72.7, V71.7 (74)
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