04-04-2017, 05:22 AM
(04-03-2017, 04:52 PM)Mondial Wrote: Yes that looks correct now.
If you want to do it right, you really need to have a new transformer made, or find a good one from another chassis. It is not your usual driver transformer. Note that it has two separate secondaries with each driving its own 6L6.
The reason for this is that negative feedback is applied from the opposite 6L6 plate to the bottom of each secondary through caps 115 and 119. Without separate isolated secondaries you cannot accomplish this, and the output stage will not work as designed, with higher distortion and reduced speaker damping.
Until you find the proper transformer, the resistor mod should work, but you will not get full output. You can also try replacing the resistor with a low current audio choke of 20 Henries or more. This will give more drive and greater power output.
Thanks Mondial. I haven't heard from Heybour yet, but I hope they are able to recreate one for a reasonable cost. I was really hoping the parts set would have a good interstage transformer but same issue.
Andy Sorrell
Palmyra, Virginia