Author Topic: my 12au6 preamp schematic  (Read 1370 times)


my 12au6 preamp schematic
« on: March 10, 2015, 07:43:53 PM »
Here is my 12au6 cathode bias preamp schematic it has a very clean clear sound and a massive volume boost. It is running from two separate power supplies. The heater supply is 9vac@400ma and the plate supply is 32vdc@1560ma. It is rack mounted with both transformers inside the 1 space rack unit and a 120vac plug out the back. I added a big muff pi style tone stack and a standby switch that cuts the power from the 32vdc supply and switches to bypass, but the heaters stay on so its ready to go when flipped back on. I also built a 12au7 version into a stompbox it runs @ 18vdc 2.23a and has massive amounts of gainy distortion any one see anything that could be improved upon im open to suggestions.
« Last Edit: March 10, 2015, 08:04:56 PM by mountianjustice »


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Re: my 12au6 preamp schematic
« Reply #1 on: March 10, 2015, 08:32:10 PM »
Cool! Where's the sound clips?  ;)
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