ARP 2600

ARP 2600 circuit board work
We forgot to take a picture of it when it was done, so here’s a picture of it when it was dirty!

The owner of this ARP 2600 got it in an insane trade in the late 80s… in exchange for a Peavey keyboard amp and a TR-505! A lot of it had never worked in the entire 30 years he had had it.

When we do restoration of an ARP that’s in bad shape, we’ve learned that there’s really only one good way to approach it. We basically strip it down to its bones and do everything we possibly can in one fell swoop before even trying to test different systems. It ends up being so much more efficient that it actually costs less than taking a more step-by-step approach.

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ARP Avatar – Retroaktiv patch bay kit installation and the vintage synth modding controversy

ARP Avatar with Retroaktiv “Modular Patch Bay Kit”

This was a pretty big mod project that Darian finished a few weeks ago on an ARP Avatar, the ARP guitar synth which is mostly just a keyboardless Odyssey with a bunch of guitar-processing junk that no one cares about. That’s just a fact. Anyway, several years ago New England Analog developed this kit to break out a lot of the CV input points and modulation sources of the synth’s architecture to 1/8″ jacks mounted on a single long PCB, and now that New England Analog has closed, a new version of the kit is available from Retroaktiv. Continue reading “ARP Avatar – Retroaktiv patch bay kit installation and the vintage synth modding controversy”

EML ElectroComp 101 – 1 volt per octave conversion mod

Update, 8/2019: we are now selling PCBS and kitsf that make it easy to install this mod! Click here for details.

This is a really fun synth! EML was a lesser-known American synth company competing with Moog and ARP during the 1970s and made some unique instruments. The EML-101 is a semi-modular duophonic synth similar in structure to the ARP 2600 and very unique and powerful. The bulk of our work on this involved designing and installing a circuit that allows the synth to accept standard 1 volt per octave-scaled CV via its “SEQ” input, as its oscillators have an unusual scale of 1.4 V/octave with a 4.6-volt DC offset. Continue reading “EML ElectroComp 101 – 1 volt per octave conversion mod”