Music Man 120 2247 Low Output

[Mr_bibbles]

Ok, let me see if I understand, I have almost no experience with these tests.

8ohm tap (orange)---> filiment.
Common tap (black) ----> filiment
All others disconnected, measure the AC voltage from 8ohm to 4ohm tap, also from 8ohm to both plate windings and B+ winding?

[g1]

Ok, let me see if I understand, I have almost no experience with these tests.

8ohm tap (orange)---> filiment.
Common tap (black) ----> filiment

Yes. All other wires disconnected. Now double check that there is 6.3VAC between those 2 wires.
If so:
1) What is AC voltage between wires that go to plates?
2) What is AC voltage from B+ winding to each of plate windings.