Music

Acoustic accordion MIDIfied for the digital age

Acoustic accordion MIDIfied fo...
Brendan Vavra's DIY MIDI accordion digitizes key, button and bellow action to create MIDI music
Brendan Vavra's DIY MIDI accordion digitizes key, button and bellow action to create MIDI music
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Brendan Vavra's DIY MIDI accordion digitizes key, button and bellow action to create MIDI music
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Brendan Vavra's DIY MIDI accordion digitizes key, button and bellow action to create MIDI music
The Arduino Mega and key sensors to the left, and the button sensor setup to the right
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The Arduino Mega and key sensors to the left, and the button sensor setup to the right
Each of the removed buttons were shaped differently, so Vavra created a custom storage rack to keep track of location for reassembly of the accordion
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Each of the removed buttons were shaped differently, so Vavra created a custom storage rack to keep track of location for reassembly of the accordion
Vavra only had to digitall map 24 pad location for all 120 buttons to work in MIDI
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Vavra only had to digitall map 24 pad location for all 120 buttons to work in MIDI
The Arduino Mega at the heart of Vavra's DIY MIDI accordion
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The Arduino Mega at the heart of Vavra's DIY MIDI accordion
Vavra bought an acoustic accordion on eBay for US$150, which was in good working order but the reeds "were completely shot," making it unusable without repair
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Vavra bought an acoustic accordion on eBay for US$150, which was in good working order but the reeds "were completely shot," making it unusable without repair
Vavra added a Bluetooth transceiver for wireless connection to a computer and a barometric pressure sensor to allow the bellows to add dynamic expression
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Vavra added a Bluetooth transceiver for wireless connection to a computer and a barometric pressure sensor to allow the bellows to add dynamic expression
The sensors and Arduino Mega installed under the 19.25-inch piano keyboard
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The sensors and Arduino Mega installed under the 19.25-inch piano keyboard
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Though manufacturers like Roland have been selling digitally-driven accordions for a number of years, they're not exactly wallet-friendly. Accordionist, composer and software developer Brendan Vavra opted to take the DIY route, transforming a relatively cheap, non-working acoustic instrument he bought on eBay into a capable MIDI music maker.

Vavra bought an acoustic accordion on eBay for US$150, which was in good working order but the reeds "were completely shot," making it unusable without repair. This wasn't something that concerned Vavra too much, though, as it was bought to be sacrificed at the alter of digital music.

He began by breaking apart the left hand Stradella bass system, removing and cleaning each of the 120 buttons – which were shaped differently under the business end, meaning that he had to keep track of each button's location for reassembly once the electronics had been installed.

The buttons in the accordion actually led to just 12 bass key pads and 12 chord key pads, so Vavra only needed to digitally map 24 pads to have all 120 buttons work in MIDI. Button movements were detected and converted to digital signals with the help of photo interrupters, which were blocked and unblocked when buttons were pushed.

The Arduino Mega and key sensors to the left, and the button sensor setup to the right
The Arduino Mega and key sensors to the left, and the button sensor setup to the right

A similar process was undertaken for the 41 keys of the instrument's right hand 19.25-inch keyboard, and the circuits and sensors were connected to an Arduino Mega processing heart powered by USB. The last additions to make it into the build were a Bluetooth transceiver to allow for untethered connection to a computer running music production software and a barometric pressure sensor used to pump up the volume and cook in some dynamic expression using the accordion bellows.

Vavra reports that the total cost of the conversion was in the region of $400, not including tools and solder. Though not as capable as Roland's V-Accordions, or more modern takes on the form factor, we think the DIY MIDI accordion looks the business and performs pretty well. You can judge for yourself in the video demo below, and if you're suitably inspired to build your own, Vavra has overviewed the project on GitHub (see source link).

Source: Brendan Vavra

DIY MIDI Accordion Demo - Stolen Moments (by Oliver Nelson)

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1 comment
WarrenHarding
Hmmm... What's next? MIDI capable bagpipes??? :-)