Aphex Twin’s MIDI-modified Yamaha GX-1 is up for sale – for just £100,000With less than 100 ever produced, the three-tiered Yamaha GX-1 is  something of synth legend. First released in 1973, the extremely rare model marks Yamaha’s historical entry into the synth market. And one is currently up for auction for £99,950.
But this isn’t an ordinary GX-1. The synth was once owned by none other than electronic visionary Aphex Twin. While in his possession, he also asked Colin Fraser of Sequentix to restore the synth to its former glory, as well as requesting the addition of MIDI functionality.

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While the synth was first owned by British producer Mickie Most, who worked with the likes of Lulu and Hot Chocolate, Aphex Twin acquired it in the late ‘90s. Aphex Twin would go on to use it for his side project, The Tuss, notably on GX1 Solo, which showcases the synth’s hazy beats and futuristic whirring.
According to an interview shared by Sequentix back in 2014, Aphex Twin was enamoured with his GX-1 – and had big dreams for its restoration. “It is the best sequencer ever made ‘til now, in terms of analogue input/output, timing,” he said “It’s got a long way to go, but I can’t endorse it enough!”
“I’ve never been into endorsing anything – I’ve been asked by a lot of people but i hate the idea of it, makes my skin crawl…” he continued. “[But] Colin [Fraser] is totally on it and in it for the right reasons. I hope Colin does really well out of it, he deserves to. The guy’s a genius.”

According to the auction listing on Vemia, the custom-modded GX-1 is in “gorgeous condition” following its restoration. And it does look gorgeous; the brushed chrome and off white aesthetic of the three-tiered polyphonic analogue synth makes it look like something out of a sci-fi film.
“After some painstaking work at the Sequentix studio it is in full working order as envisaged by Yamaha all those years ago,” the listing reads. “It is complete, with the main console, bench, pedals, two massive speakers, two programmers, and all cabling.”
Credit: Vemia Auction Listing
Fraser is also open to adding more custom modding for whoever wins the auction. “[While] one person might want the GX1 as original as possible, another might want bells and whistles,” the listing says. “Colin has designed and prototyped a programmer for the extended sound capabilities he has envisaged. If required, he could extend the MIDI capabilities to the bass pedals.”
Fraser is also currently in the process of “producing a preliminary brochure for his MIDI retrofit” for anyone keen to explore the “the depth of his exploration of the GX1’s architecture”.
Credit: Vemia Auction Listing
Online forums have been trying to work out just how many GX-1s exist for years. A Gearspace thread from 2016 pinning down a list including Keith Emerson, Hans Zimmer, Led Zeppelin’s John Paul Jones, Stevie Wonder, ABBA, and, of course, Aphex Twin.
The Vemia auction starting bid sits at £99,950, and is scheduled to end on April 12.
Credit: Vemia Auction Listing
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