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Hoffman Amps Forum image Author Topic: Stand Alone JCM800 Preamp Help Please  (Read 2757 times)

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Offline ncusack

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Stand Alone JCM800 Preamp Help Please
« on: October 24, 2012, 10:59:55 am »
Hello Everyone,

I have a friend who would like me to build him a stand alone jcm800 preamp for studio work. I've never done anything like that before and would like to know if it would be as easy as finding an appropriate power transformer for the right preamp voltages and just tapping off the master volume for the output or if there needs to be a little more to the circuit in order to get a useable signal out. I know he's looking for something like the 2204 100W master volume sound if that helps.

I'm just looking for a starting point to run with if anyone can help.

Cheers,

Neill

Offline SILVERGUN

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Re: Stand Alone JCM800 Preamp Help Please
« Reply #1 on: October 24, 2012, 11:08:28 am »
Doug did a stereo tube preamp here:
http://www.el34world.com/projects/StereoPreAmp1.htm

Check there for his schematic, layout, voltages,

Maybe that will shed a little light on your design.....good luck,,,,that sounds like fun!

 


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