Complete Guitar Wiring Launching soon

Ok… So, I have some news to share that makes me pretty excited. It's a biggie for me and it's been a while coming so, you know… butterflies, excitement, nervousness, crippling anxiety, that sort of thing.

I'll go into more detail over the next while but, for now, I'll say this:

Complete Guitar Wiring will launch on Friday February 18th.

It's my new book. And I've tried to make it as 'complete' as the title suggests. We're talking 400 pages of information on guitar wiring. There's a lot in there and, between now and the 18th of February, I'll talk some more about it. For now, though, it feels like a good excuse to talk about some guitar wiring stuff. So, let's take a sort of 'primer' look at guitar circuits and see how they're put together. I'm going to begin at the beginning (well, close to the beginning) and explain some basics on this. Let's get started…


How a guitar circuit works

A very basic electrical circuit

Wait! That's not a guitar! Yeah, yeah. Bear with me. Maybe back in school science class you looked at electrical circuits. One of the most basic circuits is shown above. It's a battery that provides a current to illuminate a light bulb. The battery's chemical energy generates a current that passes through the light bulb, heating the filament before making its way back to the battery and completing its circuit. That's important. It has to make the journey all the way back to the battery in order for anything to work. It's called a circuit because the current has to make a circuit all the way around. The current shoots out the positive side of the battery and returns on the negative.

A simplified basic guitar circuit operation

Look familiar? We've added a pickup in place of the battery. Simplifying things, we can think of the pickup as a little electrical generator. Where the battery generated a current from chemical energy, the pickup generates one by sensing the strings vibrating in its magnetic field—it changes the strings' kinetic energy into electrical energy.

That energy (or signal, if you like) shoots out of the pickup* and makes a somewhat larger circuit, out the jack and through an amplifier where it's embiggened and changed to audio that comes out out the speaker. For anything to work, though, the signal has to complete its circuit back to the pickup so, it travels back up the guitar lead, through the jack and back to the pickup.

We usually call the 'outbound' signal path the hot wire (red in the drawing) and the return path happens on the ground wire (black).

*A little aside to note that, in reality, things are a bit more complicated than a signal shooting out the hot wire and back the ground wire. These guitar signals actually alternate back and forth many times a second but, for the purposes of understanding this, it's fine (and useful) to pretend the signal squirts out in one direction only.

Controlling the circuit

So, we've invented the electric guitar and the whole place is rocking. It's a bit noisy though. What if we don't want things to be so damn loud?

Adding a volume pot to the circuit

We stick in a device called a potentiometer. A potentiometer—for excellent reasons, abbreviated to 'pot'—is a variable resistor. A resistor makes it harder for an electrical signal to pass through it and a variable resistor allows the amount of resistance be controlled. Above, we've added a volume pot to our guitar circuit.

The signal still shoots out of the pickup but this time it passes through the volume pot before travelling out through the jack and lead. Fully rotated (at 10) the pot offers no resistance to the signal and it happily rocks along to the amp as it did before.

As you begin to turn the volume control down, though, more resistance is introduced between the signal source and its path out to the amp. Less of the signal can force its way through this resistance and so, the sound from the amp becomes quieter.

At the same time, the resistance between the signal source (the hot) and the output is being increased, the resistance between parts of the signal path and ground is being decreased. I won't get too far into that right now, but sending a signal to ground is a great way to kill it.

And so we have a basic guitar circuit. Of course you can add additional pickups, switches, tone controls, and more volume controls but this is really the foundation of all guitar wiring. In Complete Guitar Wiring, I show how you can continue to build on this and discuss how and why the various controls work like they do.

Like I said, I'll be emailing more about Complete Guitar Wiring over the next couple of weeks. I'll take the opportunity to discuss some more wiring stuff too so it won't be all one-sided. And, I think I'll have even more news about even more stuff that might be useful.

Stay tuned for more. If you've questions, hold off a little while and I'll probably cover them soon. I've got a busy couple of weeks ahead. I'll talk to you real soon.