7

How I Made: Electric synth guitar

FEATURE

instead of capacitance. It’s the part of the
project that most frustrates me (particularly
because I have since seen a similar project
with capacitive touch working fine), but it
was necessary in order to push the guitar
towards completion.

BEYOND THE ALTOIDS TIN
My previous musical electronics projects
have always suffered in both their

aesthetics and reliability. I have shown up

to gigs with Altoids tins stuffed with badly

soldered wires, and I have had a large

audience wait patiently for me to debug a

robotic glockenspiel with a fried stepper

motor. This time, I told myself, I wanted

things to be different.

My plan was essentially to build a strong

box in the shape of a guitar, with as much

room as possible for circuitry inside. I

sketched a design that evoked a Fender

Stratocaster using only straight lines,

partly for the angular eighties aesthetic

but mainly for ease of construction. With

the hazy recollection of my A level in

woodwork, I constructed the design from

MDF and scrap wood, attempting to over-

engineer wherever possible with judicious

use of wood glue, screws, and bolts.

Having built a sturdy body, I wanted

to make the electronics similarly reliable.

Realising that I would need to tweak

or repair the circuitry at some point, I

tried to make the system as modular as

possible, using headers to attach elements

such as the potentiometers to the main

circuit board. While I think this approach

was broadly correct, I made one major

mistake: I designed the main circuit board

to be mounted to the bottom part of the

guitar, while the potentiometers, buttons,

and switches were mounted on the top

surface. This meant that both assembling

and troubleshooting the circuit were tricky

tasks, with tangled wires spanning two

An accidental remake

Halfway through this project, I stumbled
across a very similar ‘guitar’ from the eighties:
a MIDI controller called the SynthAxe. It too
had six-part frets and separate strings for
the left and right hands, and initially I was
annoyed that ‘my’ idea had already been done
(in my own county of Oxfordshire, in fact!).
However, the SynthAxe originally retailed for
£10 000 and failed to catch on, despite later
developing cult interest, so I felt justified in
pushing on with my much cheaper design,
hoping that it might allow some people who
wanted to own a SynthAxe to build their
own custom version from cheaper parts;
I estimate that I spent about £100–£200
building Bjarkardóttir.

Above

Inside the body, including a battery which

wasn’t used in the final version

Right

The fretboard, with six-part conductive

frets to detect fingering