Many musicians are also dedicated gearheads and tinkerers. And a good number of garage hackers are musicians. When a passion for gear creativity merges with the need to play something new, wondrous things happen. We've selected a few of our favorite one-off instrument creations to whet your appetite for homebrew sonic experimentation.

We start our journey into homemade hack mayhem with the Guitarduino from Igor Stolarsky. The Les Paul GT is a fine instrument in its own right, but Stolarsky wanted more – he wanted to be able to add percussion, fire strange sounds and engage synthesized oddness from the guitar itself.

So he set about fitting the GT with pressure pads, colored buttons and an Arduino Uno development board. The uppermost of the three Force-Sensing Resistor touchpads taped to the front of the guitar acts as a filter with step sequence modulation. There's a pitch shifter pad taped below the strings, between the pickups, and a synth vibrato launch pad under the neck pickup. A sensor strip running along the back of the neck serves as one long button that can extend an effect or change parameter settings in real-time.

The touch sensor signals are fed through to a Max/MSP patch running on a laptop, transformed into MIDI and then sent on to an Axe-FX II preamp/effects processor, which also receives the dry guitar signal from the humbuckers. The colored buttons, meanwhile, beat out percussive sounds, a stutter effect and live looping in Ableton Live. The combined output is nothing short of impressive, which you can hear in the demo video below.

These days, Stolarsky looks to have retired the Guitarduino in favor of using a combination of the Fishman TriplePlay wireless MIDI controller and a Guitar Wing, as you can see in the video below, but his Guitarduino creation remains one impressive noise-maker.

Londoner Sam Battle likes to have fun while making music, as can be seen in his Synth Bike 2.0 hack. The mule onto which all manner of e-music goodness is harnessed is an original, and slightly weathered, 1973 MK2 Raleigh Chopper kids bike.

Battle added a Sparkfun WAV Trigger drum machine, an analog synth, a sampler, a digital oscillator, an echo module and a built-in speaker. The Synth Bike 2.0 also rocks eight Arduino Nano dev boards. The control board sporting multiple switches, dials and knobs is mounted to the Chopper's cool horn handlebars, and more pads are positioned on the bike's top tube.

The tempo of the output can be set using a built-in clock, or determined by the spin of the front wheel – meaning the faster the Chopper goes, the quicker the beat. You can see the mobile beat machine in action in the video below.

Battle's "Look Mum No Computer" YouTube channel is stocked to bursting point with other tremendous synth hacks, including a dartboard synth and a circuit-bent Furby.

Guitarist Victor Kucher cooked up a storm last year by kitting out a genuine microwave oven with a P90 pickup, 19-fret wooden neck, hardware and strings. You can watch a run-through of how it was built in the video on Kucher's Moose On YouTube channel or see him pick his way through a cover of the theme from the Benny Hill Show in the video below.

A couple of piano keyboard projects pinged our DIY project sonar when gathering this collection together. The first is Liam Lacey's Vintage Toy Synthesizer. The project saw software engineer and maker replace the insides of an old toy piano with the electronic guts of a two voice polyphonic synth.

Key components of the hack are a BeagleBone Black computer that runs the processing show, with a C++ audio synthesis-based voice engine, and pressure sensors that register the action of the unit's 18 keys. The player tweaks scales, sounds and parameters using knobs on the piano's lid. You can hear Lacey run through some of the available sounds in the video below.

The second piano keyboard project is all analog, and a great example of precision craftsmanship. Aliaksei Zholner has previously made miniature working engines from paper, but after chatting about a music-themed project with his wife, decided to fashion a pipe organ from paper card.

Each of the 11 white and seven black keys is connected to a valve, which is kept closed when the key is at rest by strategically-placed paper springs. Air from a deflating balloon attached to the side of the instrument is routed to a chamber and up through a tuned pipe when a key is pressed.

The last time we caught up with Tom Fox was to include his guide for making a tennis racket guitar in our roundup of guitars made using household items. For his latest Dronemachine project, created for Belgian musician Quentin Stinglhamber, Fox ran eight strings between metal pegs and a wooden end block, near which is a coil from an electric fan that acts as a pickup for the strange contraption.

An additional piezo pickup is positioned at the far end, with knobs controlling the blend between the two and output volume. The drone sound starts up when a small piece of string attached to an electric motor continuously whips the strings. In the demo video below, Fox uses a metal coat hook to alter the pitch of the notes coming from the machine.

Honorable mentions

What better way to complement a red hot guitar solo than by playing it on a guitar packing a stomp-controlled flamethrower? Should creator Colin Furze ever need some firey brass to accompany him, then he could do worse than engage Valentin Guerin and his incredible flame-shootin' trombone – which you can see in the video below (skip to about a minute in for the best of the action).

That rounds out our selection of creative instrument hacks and gear experiments. Let us know in the comments if we've missed any of your favorites.

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