ISLA Instruments' ARP Quadra

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via ISLA Instruments Reverb

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Pics of the inside below.

"This classic behemoth has had many, many hours put into it to bring it back to its former glory.
If you're looking for a Quadra, I think this one is well worth considering as it is now a fully working, reliable synth with a lot of care and attention put into it.

I will purchase a FLIGHT CASE for this synth prior to shipping, at my cost.

Work Carried out:

Complete power supply rebuild (including all new regulators and capacitors)

COMPLETE polarized capacitor replacement throughout the ENTIRE synth (all tants and electrolytics)

ARP Filter modules removed and re-capped (using audio grade caps in the filter audio path)

Brand new Keyboard control PCB fitted (battery damage had ruined the original board)

Brand new Memory backup battery fitted (average 20-25 year life span)

Extensive Logic chip replacement.

Keybed stripped, chassis painted and keys re-bushed (feels like new again)

All sliders and switches completely stripped, cleaned, re-lubricated (and replaced with NOS where needed)

Brand new set of slider knobs fitted

Full Calibration

This synth will also be supplied with a beautiful (and extremely rare) original bound service manual (see photos)


The not so great:

The touch sensitive bar that runs underneath the keybed is not as sensitive as it probably once was, if this bothers you there are a couple of vendors out there that sell replacements.

There are a few scuffs and blemishes (see photos)

A dent in the bottom of the enclosure at the back of the synth (see photo)"