Acoustic Bass Preamp Replacement

Written By: Juan Chavez

Comments: 0

Difficulty

Moderate

Steps

Time Required

1 - 2 hours

Introduction

This guide will go over retrofitting a new preamp into your acoustic bass.

You can also use this guide to retrofit a preamp into a guitar, as most of the process is similar.

Make sure that the Preamp kit you buy fits your bass. Ideally, looking for a preamp in-store rather than buying the kit online will save you time returning the product and looking for another kit.

Tools

Parts

Acoustic Preamp Kit

Step 1

Use a guitar string winder to remove each string carefully.

Step 2

Look inside the bass for the preamp tuning box.
Unplug the small jack.

Step 3

Cut the zip tie holding the excess length of wires in place, located inside the bass.
These are most likely right under the bridge of the bass.
This will allow you to disassemble all parts the wires will connect to later on in the repair.

Step 4

Pull out the pick-up stick from the bridge of the base.

Step 5

Look for the tuner/equalizer/preamp and carefully remove each screw using a Phillips screwdriver.
Also, look for the endpin jack and remove it.
In this case, the part had already fallen off. Refer to the second image if you have trouble finding the endpin jack.

Step 6

Place the tuner over the area you removed the previous one from.
Scratch a line around the opening to the area of the bottom portion of the tuner.
Refer to the second image for a visual reference.
Ensure the scratched guideline is made to the parameter of the parts behind the face of the tuner.

Step 7

Using one of the metal files, file up and down, following the outline.
Continue this until the desired opening is made.
This will most likely take a long amount of time. If you have access to a small jab saw or similar power tool it will speed up the process.
Do this step ideally in a well-ventilated area as the wood shaving are small, and you may inhale them and wear protective gear like a face mask.

Step 8

Get your output platform and measure the perimeter of the parts under the face with the screw holes using a ruler.
The second and third images show the underside of the part, measuring around the internals.
Once you measure each side, jot them down for Step 9.

Step 9

You will use a pencil and paper to outline the measurements jotted down.
Cut the shape out using a pair of scissors.
Place the paper over the opening on the guitar and scratch the perimeter of the paper.

Step 10

Insert the file into the opening and file up untill your reeach the outline done.
Then follow the guidelines until the opening is completely cut out.
Do this step ideally in a well-ventilated area as the wood shaving are small, and you may inhale them.

Step 11

Get a power drill using a Philips head screw. And your four screws to complete this step.
Then place the preamp into the opening and directly screw in the screw with your power drill.
A power drill is required in this step. This will allow you to create a hole to screw in the screws or just directly screw in the screw without drilling holes.

Step 12

Using your power drill and the other four screws, drill the screws into the output platform openings.

Step 13

Get your pickup stick and insert it into the hole in the bridge.
Look into the guitar for the end of the pick-up stick and pull it until it reaches the preamp box.
Plug in the pickup stick jack into the box, as seen in the fourth image.

Step 14

Look for the preamp inside the bass. Your will find a wire showed in the first image.
Stretch your arm into the bass to reach the output platform, where you will see where the wire will plug into.
Ensure the wire plugs in the right way and is firmly plugged in.