This Custom Synth Packs in the Sound with 200 Modules

Craft & Design Music Technology
This Custom Synth Packs in the Sound with 200 Modules

An array of brightly lit knobs and dials sweeps up the wall inside a handbuilt wooden case. John Karbassi regularly switches out any number of the 99 modules – oscillators, amplifiers, filters, sequencers, etc. — to play with new combinations and sounds. The modules aren’t hardwired together; the connections are made via patch cables. “You’ve got total control over the sounds, patterns, and timbres you pull out of the synthesizer — and total flexibility to creatively abuse it,” says Karbassi.

Photography by Tyler Koltz

The decision to build a curved case came after Karbassi realized that the tall cases he’d been using were a pain to play for long periods of time. For this one, he maximized ergonomics by fitting the curve to the length of his arm.


With around 200 modules, each with an average of 100 parts, and with each part averaging 3 solder joints, Karbassi estimates that he’s flowed about 60,000 joints in his modular journey. He’s been making them for over 10 years. When he became frustrated with prices and accessibility, he founded Modular Addict to help remedy that. “Turns out, people dug the idea,” he says. “Business has really exploded.”


Now, Karbassi notes an improvement across the board for DIY synth kits and PCBs in terms of variety, quality, accessibility, cost, and simplicity. “If you know how to solder,” he says, “you can build a synthesizer.”


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Sophia is the managing editor of the Make: blog. When she’s not greasing editorial gears, she likes to run, ride, climb, and lift things, and make lo-tech goods like zines, desserts, and altered clothing. @sophiuhcamille

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