GTR Onboard Preamp Module

Catch-all Jerry Garcia style preamp module.  This is an in-guitar version of our Boost of the Dead pedal.  Putting the buffer and boost directly connected to the pickups for maximum signal integrity.

The first circuit, switch closest to the volume knob, is a take on the Jerry Garcia Tiger Buffer.  This buffer cleans up the signal really nicely, it adds clarity and sparkle.

The second circuit, switch closest to the tone knob, is a take on the Stratoblaster circuit. Before the Tiger Buffer was put into Jerry's guitars, he most utilized the Alembic Stratoblaster. It fattens up and adds growl single coils. Great on it's own and made even sweeter when the Tiger Buffer is engaged before it.

Designed to fit into most Fender/Squier stratocasters.  The image above with the guitar shows the location of the switches once installed. 

We highly recommend shielding the cavity and pick-guard when installing this preamp. It will, by nature, amplify any interference picked up by the guitar, and shielding will help mitigate any unwanted interference.


1: Master Volume, C500K

2: Master Tone, A500K 22NF Cap

3: Boost Gain, C50K

Switches are true bypass allowing the guitar to still be played if the battery dies or there is no battery.

Signal chain:

Wire from pickup or pickup selector > preamp module > tone control > buffer > volume control > boost > output jack

This preamp module does not pretend to make you sound like Jerry, is not a part for part clone of any other pedal, and doesn't guarantee anything to anyone... I built this for fun, and it should be used to have fun.

Installation Instructions

Modifying a guitar can damage or destroy it... the buyer is taking on full responsibility for any damage done to their guitar.

Included in this unit: Completed board with pots & switches, Stereo cable jack, 9 volt battery strap. 

Not Included in this unit: Set-screw Knobs

Purchaser will need to have familiarity with soldering and guitar modification. 

Wire from pickup selector is soldered to the eyelet labeled I, in-between the battery strap and ground connectors.

There are two free eyelets next to the I eyelet for ground.  The third ground eyelet has a copper wire soldered to the volume pot.  The two remaining eyelets can be used for ground wires.  The copper wire soldered to the volume pot can also be used as a ground solder rod.

There are three long wires attached to the board on the Blast side of the board.  These wires should be snaked to the jack cavity and soldered to the stereo jack provided.  The wires are labeled on the board as T, R, & ST goes to the Tip of the jack.  R goes to the Ring of the jack.  S goes to the sleeve of the jack.  This is situated so that the battery is only grounded and completing a complete circuit when a guitar cable is engaged.  When the guitar is unplugged the battery is disconnected, saving battery life.

The battery strap can be placed anywhere you want.  We recommend drilling through the pickup cavity through the back of the guitar into tremolo cavity.  The tremolo cavity makes a nice easy place to put a battery.  There are bunch of ways to make battery compartments, you do you.

The battery wires are soldered to the board on the battery strap terminals.  Red is +, Black is -.

Two holes will need to be drilled through the pick guard for the switches.  Consult the template included with purchase.

Because of the nature of this item, it cannot be returned once it's been purchased without a written statement from a professional guitar tech outlining defects in the product.  Each board has been tested prior to shipping.

We recommend bringing this module to a professional guitar tech to complete the installation. 

This item is sold As-Described

This item is sold As-Described and cannot be returned unless it arrives in a condition different from how it was described or photographed. Items must be returned in original, as-shipped condition with all original packaging.Learn More.

ConditionBrand New (New)
Brand New items are sold by an authorized dealer or original builder and include all original packaging.learn more
  • GTR Onboard Preamp Module

Farm Pedals

Casco, ME, United States
Joined Reverb:2015

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