11
Close up the guitar
Install the pot into the pickguard if you haven’t already done so and close up the guitar
MODIFYING A POT ALREADY IN THE GUITAR
You may wish to use a pot already installed inside the guitar such as an unused volume or tone control as
the pot for the MidiUp to avoid having to install a new one. Most pots used in guitars are of the 250K to
1M ohm variety so will work with the MidiUp. It is highly recommended that unless you are familiar with
guitar electronics, that you leave this particular modification to your guitar repair shop.
Although guitar wiring varies greatly from guitar to guitar which makes it impossible to offer specific
instructions, generally speaking, the following rules will apply:
Bypassing the volume control
The volume control connects between the signal (from the pickups or selector switch) and ground and the
center tap goes to the output (or to the selector switch). Therefore to bypass the volume control, leave the
end that is connected to ground alone and remove the wires that are connected to the other two terminals
and connect them directly together. Leaving two empty lugs on the pot and no unconnected wire. Then
take a single wire and solder it between the center lug on the volume control and the ring (center connector
) on the stereo pot.
Bypassing the tone control
Bypassing a tone control usually just means disconnecting all of the wires from the pot and not connecting
the removed wires either to each other or to anything else. There is usually a capacitor connected to the pot
and this should be removed completely. Once the pot is disconnected from the circuit, then you can wire it
up in the same way as described in the last section for wiring up a new pot.
TESTING THE MODIFICATIONS
After closing up the guitar connect the guitar to the input of the MidiUp using a high quality stereo (TRS to
TRS) cable. Connect a regular mono instrument cable (TS to TS) from the output of the MidiUp to the
guitar amp. If you get sound from the guitar to the amp, you know that part of the connection is wired
correctly.
Now turn the pot for the MidiUp from one extreme position to the other and check that the HI/LO LED on
the front panel lights when the pot is at one extreme and then at the other. There will be a small amount of
rotation left over on either side of the pot after the LED lights. This is normal.
If these two checks work out, then you have successfully completed the job.
