El34 world logo

Pots-Knobs Foot Pedals Switches Fuse Holders-Cords-AC Items
Jacks-Plugs-Connectors Tube Sockets Pots-Knobs Hoffman Turret Boards
Tubes-Valves Circuit Board Building parts Eyelet Boards Tools and Batteries
Bike Light Parts Switches Jacks-Plugs-Connectors Misc Hardware-Grommets-Feet-Ring terminals
Pots-Knobs Jacks-Plugs-Connectors Lamps-Diodes-Channel Switching Hoffman Turret Boards
Chassis-Boxes Fuse Holders-Cords-AC Items Screws-Nuts-Washers Screws-Nuts-Washers
Tube Sockets Circuit Board Building parts Fuse Holders-Cords-AC Items Tools and Batteries
Capacitors Tube Sockets Wire-Cable-Heat shrink Tube Sockets
Capacitors Switches Screws-Nuts-Washers Jacks-Plugs-Connectors
Resistors Capacitors Tube Sockets Eyelet Boards
Jacks-Plugs-Connectors Handles-Amp Trim Parts Switches Lamps-Diodes-Channel Switching
Capacitors Handles-Amp Trim Parts Tube Sockets Jacks-Plugs-Connectors
Transformers Eyelet Boards Pots-Knobs Handles-Amp Trim Parts
Handles-Amp Trim Parts Hoffman Turret Boards Tools and Batteries Screws-Nuts-Washers
Foot Pedals Fuse Holders-Cords-AC Items Lamps-Diodes-Channel Switching Capacitors
Transformers Resistors Pots-Knobs Handles-Amp Trim Parts
Chassis-Boxes Lamps-Diodes-Channel Switching Jacks-Plugs-Connectors Wire-Cable-Heat shrink
Tools and Batteries Pots-Knobs Books Resistors
Circuit Board Building parts Jacks-Plugs-Connectors Misc Hardware-Grommets-Feet-Ring terminals Jacks-Plugs-Connectors
Circuit Board Building parts Wire-Cable-Heat shrink Lamps-Diodes-Channel Switching Switches
Hoffman Turret Boards Tubes-Valves Guitar Strings Foot Pedals
Reverb tanks and Bags Resistors Lamps-Diodes-Channel Switching Fuse Holders-Cords-AC Items
Tools and Batteries Jacks-Plugs-Connectors Transformers Tubes-Valves
Tube Sockets Lamps-Diodes-Channel Switching Wire-Cable-Heat shrink Tube Sockets
Screws-Nuts-Washers Jacks-Plugs-Connectors Capacitors Capacitors
Tube Sockets Tubes-Valves Misc Hardware-Grommets-Feet-Ring terminals Hoffman Turret Boards
Bike Light Parts Transformers Lamps-Diodes-Channel Switching Lamps-Diodes-Channel Switching
Fuse Holders-Cords-AC Items Pots-Knobs Pots-Knobs Wire-Cable-Heat shrink
Pots-Knobs Handles-Amp Trim Parts Jacks-Plugs-Connectors Pots-Knobs
Tubes-Valves Pots-Knobs Pots-Knobs Transformers
Capacitors Tubes-Valves Tube Sockets Switches
Capacitors Capacitors Lamps-Diodes-Channel Switching Misc Hardware-Grommets-Feet-Ring terminals
Pots-Knobs Jacks-Plugs-Connectors Transformers
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