JW said:
Schematic here: https://groupdiy.com/index.php?topic=51980.msg661595#msg661595
Thanks for the response JW!
I have that manual already, though. While the schematic in the manual does indicate FINE GAIN and PAD circuitry specifically, and polarity and rumble filter ( sorta? ), in a perfect world I'd like to have a schematic that also includes phantom power, input and output controls, and maybe even a meter. The meter not necessarily a deal breaker along with maybe the input / output volume controls. I understand that the real preamp didn't offer these 'extra' features as built in features hence why they are not present in the available schematics for the actual unit. I'm guessing phantom power, for example, was provided by separate discrete stand alone mic power supplies used to power the tube mics in play in the studio, hence why the real preamp device didn't have built in phantom power?
Maybe all of these features are easily added by someone with more electronics engineering skills than I, and... I have no problem trying to learn what I can, but at this point given my experience level short of someone with expert knowledge double checking whatever I might be able to add to the schematic, I'd be reluctant to spend the money for parts just to 'test' a guess on my part. Finding threads of how to add volume controls, phantom power and other sub circuitry to circuits is easy enough on the InterWebs, I'm never sure how exactly any of that would be baked into an already proven circuit design without possibly making serious assumptions and / or errors.
At the end of the day, if I decide to actually embark on a build, I might just build the basic unit without any of the extra desired features just to have a working example in hand, then I can play with adding features one at a time making sure each addition works without affecting the overall performance in any detrimental manner.
Cheers!