Nice one Jim.
What trimmer settings did you start out with?
I actually started with the pots at the factory default of 1/2 way. Nothing was moving until the bias pot was adjusted a good number of turns.
As bias built, offset was zeroed, more bias, null offset again...
Because of the caps in the bias circuit, the amp reacts slowly to the changes in the pots.
Are the Jensen transformers going to be available separately or will I have to purchase as a set with the boards? So far I have not go a reply from CineMag, I may have to do it the old fashioned way and pick up the phone. Any more hope for a group buy on the Jensen? I can't get to excited about this until I can at least get the transformers.
In the beginning the boards will be packaged with the Jensen transformers.
The boards may be available by themselves.
Not sure about just the transformers.
The boards may be available by themselves.
Not sure about just the transformers.
If there's enough interest I'm still willing to do a GB for the transformers. However, I'd think most would prefer to buy them together with the boards.
A nice little package with some Jensen transformers in it arrived today(thanks Buzz)
I will hopefully post some pics tomorrow and may even have one channel up and running
I will hopefully post some pics tomorrow and may even have one channel up and running

PHEW that's a relief; it works😀 Thanks for the advices Jim and Nelson for designing another good un.
The amp is biased up at 0.6V across the 0.47R source resistor with offset fluctuating slightly around 2mv and heatsinks at 40C after an hour.
Listening to JJ Cale through the stunt speakers.
I will post pics this evening.
The amp is biased up at 0.6V across the 0.47R source resistor with offset fluctuating slightly around 2mv and heatsinks at 40C after an hour.
Listening to JJ Cale through the stunt speakers.
I will post pics this evening.
The prototype diyAudio PCB. Layout by member Didiet78.
Thanks! Will the board be adaptable for SS outputs without kludging?
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