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Capacitors Hoffman Turret Boards Jacks-Plugs-Connectors Jacks-Plugs-Connectors
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Hoffman Turret Boards Tools and Batteries Capacitors Misc Hardware-Grommets-Feet-Ring terminals
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Stereo Pre Amp project

 This project is an all tube stereo Guitar pre amp is a 2 high rack unit.
The stereo outputs let you do ping pong delays and other true stereo effects such as chorus.
I happened to have a few pieces of a rack unit laying around and so I pieced together what I had and used some poplar to make the wooden parts.

If you purchased a 2 high rack unit, you would have to figure out how to make a divider
Click on the images below to see a larger image
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Here's the board with the lugs mounted The board with parts mounted
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Rear view of pots.
The bridge switch lets me plug into channel one and the guitar signal is then fed into both channels.
Other wise each channel is separate when the switch is off.
Click on the images below to see a larger image
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Front view Rear view. The jacks are the outputs for each channel.
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Completed inside view External view without Face Plate
I made the rack ears from 6061 aluminum

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image Hoffman Stereo Pre amp
Power supply view Layout with voltages
The power supply board sits above a 125C3A choke.
There is a 1/8" groove on both sides of the board.
The board slides into the groove from the rear and then the rear power cord panel was screwed into place.
The power transformer is a Mojo 779 reverb unit power tranny.
The front panel has a SPST on/off switch, a LED and a fuse holder.

Updated pictures with face plate
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Front view of my rack setup
Top to Bottom Items in rack
Palmer Speaker emulator - Load Box
Stereo Pre Amp
Stereo Power Amp

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