via this auction
"ARP 2601- The sale includes the synthesizer and matching serial number keyboard, original non copied manuals for synth and keyboard,old 1975 promotional materials, 4 patch cables, and dual 1/8" to 1/4 " synth to mixer(Amp) cables. This model is the Arp 2601P V1.0 circa 1975 with matching serial number 3620 duo-phonic LFO keyboard..This unit has the 4012 Moog ladder filter which was discontinued in the subsequent 2601P V2.0 model. It is serial number 0087 as is the serial number of the keyboard.This unit is in excellent cosmetic and functional condition for being close to 40 years old and has been brought up to showroom condition within the past year.
When searching for a 2600 , my goal was always to find a unit that had essentially been frozen in a time capsule and then replace dried out electrolytics! This is it. This synth was sequestered for nearly three decades in a closet in Calgary away from indoor lighting and moisture. Until recently, last played in 1978. Consequently, the grey faceplate shows no evidence of any fading as does the tolex.The tolex is original and exhibits no brittleness.All the 1/8" input/ outputs and faceplate nuts and screws are like new- shiney silver. Not even a hint of rust on any jack which would be evidence of poor environmental storage and moisture exposure. The internal speakers are great. No distortion or vibration at high volume.
In addition to the 12 standard photos, there is a link with 53 higher resolution photos of the synth, keyboard, and tolex cabinets/covers at all possible angles at wwwdotflickrdotcom/photos/ john316_golf ( sorry, have to list the site this way or it will be blocked by you know who).If you are serious about purchasing, you will definitely be reviewing these.
In order to bring this synth up to current standards, the following work was done in 2011 by John Smith of Davidson Electronics(NY) who apprenticed under Don Buchla:
All keyboard contacts cleaned, busbars polished, and bushings replaced(action feels great)
All tantalum capacitors were replaced
80% of op-amps were replaced
All sliders lubricated( no scratchy pots)
The typical signal path upgrade was done and the original VCA " thump" inherent in the 2600 series synths eliminated. Upgrade included replacing all gain stages in 2601 in preamp, VCF mixer, output mixer,output buffers,reverb stages, and voltage processors.
Additionally, Rob Currier of England Analog in August 2013 performed the following work:
replaced the standard 9" reverb tank with a 17" reverb spring which matched the original Blue Marvin/ Grey Meanie spring length. This spring is installed with an insulated sleeve so external vibration will not affect the reverb tank.
Replaced all voltage regulators
Calibrated the PSU to factory specs
All together, over $2800 of work was done to this synth and you would be hard pressed to find one in similar functional condition with the high quality original cosmetics of this unit .Reason for selling is I just put a 50% deposit on the Schmidt synthesizer and need to raise funds for the other 50%. That and my wife and 9 year old daughter could no longer take my full volume Frankenstein filter sweeps!This was a tough decision.I'll never find another 2600 down the road that sounds and looks as good as this one.
For anyone who has lived in a cave since 1971 and has never heard of the Arp 2600, here are a few basics:
Polyphony- monophonic(but can be patched via the 3620m keyboard to be duo-phonic )
Filter-25db self oscillating 4012(Moog) ladder with ring modulator
Osc-3 VCOs 4027 VCO 1- saw, square VCO 2-saw, square, sine, pulse, triangle VCO 3-saw, square,pulse; white noise
Envelopes- 1ADSR type 1AR type
Effects-17" spring reverb
LFO- 4015 sample and hold and many patchable options for modulation
Keyboard- 49 keys with portamento and LFO vibrato amount and rate, pitch bend knob.."
