El34 world logo

Lamps-Diodes-Channel Switching Pots-Knobs Handles-Amp Trim Parts Chassis-Boxes
Screws-Nuts-Washers Jacks-Plugs-Connectors Jacks-Plugs-Connectors Misc Hardware-Grommets-Feet-Ring terminals
Transformers Transformers Tube Sockets Pots-Knobs
Tubes-Valves Eyelet Boards Foot Pedals Circuit Board Building parts
Resistors Jacks-Plugs-Connectors Tube Sockets Capacitors
Jacks-Plugs-Connectors Tube Sockets Lamps-Diodes-Channel Switching Pots-Knobs
Screws-Nuts-Washers Fuse Holders-Cords-AC Items Transformers Tubes-Valves
Tools and Batteries Wire-Cable-Heat shrink Tools and Batteries Screws-Nuts-Washers
Hoffman Turret Boards Tools and Batteries Pots-Knobs Tubes-Valves
Bike Light Parts Books Screws-Nuts-Washers Capacitors
Lamps-Diodes-Channel Switching Tools and Batteries Hoffman Turret Boards Capacitors
Capacitors Fuse Holders-Cords-AC Items Fuse Holders-Cords-AC Items Misc Hardware-Grommets-Feet-Ring terminals
Lamps-Diodes-Channel Switching Handles-Amp Trim Parts Eyelet Boards Switches
Circuit Board Building parts Foot Pedals Pots-Knobs Guitar Strings
Switches Hoffman Turret Boards Pots-Knobs Jacks-Plugs-Connectors
Circuit Board Building parts Tools and Batteries Jacks-Plugs-Connectors Switches
Switches Wire-Cable-Heat shrink Pots-Knobs Pots-Knobs
Jacks-Plugs-Connectors Lamps-Diodes-Channel Switching Wire-Cable-Heat shrink Handles-Amp Trim Parts
Handles-Amp Trim Parts Tubes-Valves Lamps-Diodes-Channel Switching Fuse Holders-Cords-AC Items
Tube Sockets Foot Pedals Resistors Lamps-Diodes-Channel Switching
Wire-Cable-Heat shrink Hoffman Turret Boards Pots-Knobs Handles-Amp Trim Parts
Screws-Nuts-Washers Hoffman Turret Boards Misc Hardware-Grommets-Feet-Ring terminals Circuit Board Building parts
Fuse Holders-Cords-AC Items Switches Lamps-Diodes-Channel Switching Jacks-Plugs-Connectors
Fuse Holders-Cords-AC Items Bike Light Parts Jacks-Plugs-Connectors Misc Hardware-Grommets-Feet-Ring terminals
Switches Reverb tanks and Bags Jacks-Plugs-Connectors Resistors
Jacks-Plugs-Connectors Lamps-Diodes-Channel Switching Chassis-Boxes Handles-Amp Trim Parts
Pots-Knobs Tube Sockets Wire-Cable-Heat shrink Lamps-Diodes-Channel Switching
Transformers Pots-Knobs Transformers Capacitors
Capacitors Capacitors Tube Sockets Jacks-Plugs-Connectors
Pots-Knobs Tube Sockets Pots-Knobs Jacks-Plugs-Connectors
Transformers Tube Sockets Tubes-Valves Capacitors
Tubes-Valves Capacitors Tube Sockets Tube Sockets
Eyelet Boards Resistors Capacitors
You can scroll through the images above using the Image scroll controls or you can use the Left and Right arrow keys on your keyboard.

Back to Library page

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
image image
Here's the board with the lugs mounted The board with parts mounted
Click on the images below to see a larger image
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
image image
Front view Rear view. The jacks are the outputs for each channel.
Click on the images below to see a larger image
image image
Completed inside view External view without Face Plate
I made the rack ears from 6061 aluminum

Click on the images below to see a larger image
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
Click on the images for a larger image.
Front view of my rack setup
Top to Bottom Items in rack
Palmer Speaker emulator - Load Box
Stereo Pre Amp
Stereo Power Amp

Enter My Tube Amp Parts Store Here

Mobile users Enter My Tube Amp Parts Store Here

Home - Ordering Information - Ordering Information - PayPal info - Returning parts - Search the Hoffman Amps parts catalog
What's New - Q and A - Links - Shipping Info/policy - E-mail Me - Amplifier Service Technicians - About Hoffman Amps
Sound Clips - LED Bike light build info - Guitar Rig and Behringer FCB1010 info
Create your own custom Turret lug board

Hoffman Amplifiers Face Book Page

The Tube amp Library of information
Click the link above for Tube amp info, Schematics, Board building information, Projects, Mods, Transformer diagrams, Photo's, Sound clips.
There are hundreds of pages of Tube amp information on my library page.

Please visit my Tube Amplifier Forum
Here's the place you can go to ask tube amplifier questions.
You will find a large community of friendly amp builders at the link above.

Check out our huge library of Tube Amp schematics here

Design your own custom Turret Board or Eyelet board

Spam Harvester Protection Network
provided by Unspam