Gio sent in a link to this interesting preamp. The builder was able to make the preamp with parts on hand. I’m not sure I would have the tubes, but the rest of the parts are fairly common. [Thanks Gio]

I was pleased with how well it turned out, at 30 bucks it looks pretty professional with the solid gold plated jacks on the black case. A neat feature I added later on is the ability to adjust the brightness of the front LED. The yellow LED is to indicate that the tube filaments are active.

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