“ARP 2600 synthesizer with ARP 3604P keyboard (serial #’s 26888 & 36888, respectively). Restored & customized with really useful upgrades by Tim Smith of Weyer-Smith Labs/The Audio Clinic in 1995. Do a Web search for “ARP 2600″ for various descriptions of this popular analog synthesizer. The ARP 2600 was used by a wide variety of artists including Genesis (Tony Banks), Edgar Winter (on “Frankenstein”), Weather Report (Joe Zawinul), The Tubes (Michael Cotton) and many others.
After restoration, this unit sounded incredible. Upgrades, customizations & repairs included (see photos):
• replaced VCF wih 4072 filter (22kHz response), and added VCF input coupling modification to eliminated ‘thumping’ sound defect
• added +1/-1 octave switches for each VCO, and Multiples jacks
• added 4 mode envelope time extension modification for both ADSR & AR envelopes (X1-X5 modes)
• did “2600/3604/Oberheim” modification (CV1=standard; CV2=2nd voice)
• added 1/4″ output jacks (above standard mini-jacks)
• modified reverb system for better response and 14 dB less noise
• added saw/square-wave form switches to each oscillator to eliminator patch cords for this common patch
• installed standard (IEC-type) power cable interface
• replaced op-amps with BurrBrown AP2604 audiophile components, and in voltage processor section to fix Lag offset tuning problems
• replaced keyboard interface cable and cleaned jacks & plugs, and repaired, calibrated, timed & tested keyboard
• rescaled & cleaned power supply, pots., sliders, etc., and replaced defective sliders
If desired, Seller will include photocopies of ARP 2600 documentation, brochures, Patch Book, blank patch sheets, etc., that may be Seller’s possession, as well as any digital copies he has of ARP 2600 documentation, including the Service Manual. (NOTE: Original ARP documents as may be pictured in Photo#9 are NOT included, but only black & white COPIES.)
The unit has always been in a climate-controlled, clean, smoke-free, studio environment. Seller has not used it much in the past few years. When it was turned-on recently, it was not working properly. Seller’s technician looked at it briefly, but did not have time to investigate & repair it before he went overseas. Seller can refer Buyer to various qualified technicians in the U.S. or internationally. Hopefully, any required repairs will be straightforward & inexpensive, including possibly power-amps, op-amps, power transistors and/or capacitors. Therefore, Buyer is selling unit “as is.”" Link