THREE UPGRADES / MODIFICATIONS FOR THE ARP 2600
major upgrades / modifications are very extensive and
time consuming. These mods are designed for users that
are seeking to professionally "Hot Rod" their
ARP 2600 to the max. They require complete disassembly,
front panel machining, rewiring, and the power supply
in order of popularity:
VCO OCTAVE SWITCHES - 115.00
This variable version octave switch
has a position toggle and a potentiometer to dial in any
desired interval over a 2 octave range. This upgrade uses
the same high quality miniature toggle switches, military
spec potentiometers that were used on the ARP 2500 system
including a high quality 2500 style knob.
INDICATORS - 59.00 each
LED indicators providing visual feedback on both E.G.
outputs (red), s/h clock (green) and envelope follower
(yellow). Requires the power supply upgrade.
DUAL LFO -
We install 2 LFOs below the voltage
processors. They have triangle and square outputs and
also have LED indicators included. This mod, as all our
others for the ARP 2600, features high quality Switchcraft
jacks, military spec potentiometers and ARP 2500 style
knobs. Requires the power supply upgrade.
COMPARATOR / DISTORTION
This can be used to square up a waveform.
It also makes a good distortion device according to John
McEntire from Tortoise. Includes LED indicator.
ELECTRONIC SWITCH UPGRADE
The electronic switch in the S/H
section of the 2600 is almost never used because it is
missing many functions. This new upgrade we call the "Swiss
Army Knife" mod for the electronic switch. It greatly
increases the usefulness of the electronic switch in many
ways. It's a real pain to install, that is why it is pricey.
It consists of:
1. An external trig/gate input jack
to toggle the switch
2. A toggle switch to connect / disconnect the clock
3. A dedicated push-button to manually toggle the
4. 2 LEDs that indicate what side of the switch is
It can be used to obtain a clock pulse
at half the FC of the 2600 clock for triggering purposes.
The opposing gate signals can be used
to drive envelope generators or VCAs etc. for externally
triggered panning effects.
You can also use it as an audio Fc
octave divider (up to 1Khz) if you patch a pulse wave
from any VCO into the external trigger input.
SCHMITT TRIGGER - 189.00
This useful circuit is sometimes
called a trigger detector or gate detector. It is typically
used to trigger the envelopes when controlling the unit
externally by guitar or any external source. This circuit
often frees up the envelope follower so it can modulate
the filter for an auto wah wah effect, synced VCOs etc.
An LED indicator also provided. The input jack is normalized
to the output of the envelope follower.
VCO RAMP/PULSE SELECTOR SWITCHES
/ AUX OUT JACK- 60.00 for each VCO / 90.00 w aux out jack
This mod provides a
convenience switch that selects either pulse or sawtooth
for routing to the filter audio inputs. This high quality
toggle switch has a center off position so you can quickly
disable or enable the VCO outputs for easier tuning of
multiple VCOs. We also install an auxilliary output jack
next to the switch that features ramp and pulse outputs
at +5/-5. The standard factory ramp and pulse outs are
0 to +10v with a 5v dc voltage present so the aux jack
offers an alternative modulation source as well as a better
balanced audio source.
DUAL MODE FILTER - MODEL 2621- special order - call
one key element missing in a 2600 is a high-pass filter
with resonance and associated coupling circuitry. The
CMS 2620 is a dual mode, 24Db (Low-pass/High-pass), discrete,
transistor ladder filter from the CMS 9000 series modules,
Installed in the left speaker section. This original CMS
design features an innovative circuit that extracts a
high-pass response from a 24BD discrete ladder filter
circuit producing a unique sound and beautiful resonance
quite different from the existing low-pass filter in the
2600. In addition, the volume of the filter output does
not drop off drastically as the resonance is increased
as all other ladder filters do. This also makes the low-pass
output quite useful as an alternative sounding 24db low-pass
filter. Complete with anodized face plate, high quality
controls, 1/8 inch Switchcraft normalized patching. Special
link switch enables the coarse frequency control knob
of the 2627 to control both filters for a truly remarkable
sounding band-pass function (24Db x 24Db). The resonance
on the high-pass function is also very unique and distinctive.
Requires the power supply upgrade. Now comes with voltage
/ 4 CHANNEL MIXER / INVERTER - MODEL 2627 - special order
Installed in the right speaker section, this VCO utilizes
the same exact circuitry used in the other VCO's in your
2600 to assure exact tracking and pitch stability characteristics.
All four waveforms are available as well as pulse width
modulation. Low frequency mode and normalized patching
are also provided. The mixer section serves as a high
quality audio mixer with the inputs either normalized
to all 4 outs of VCO-4 or externally patched. The mixer
can also be used as a voltage summer or inverter. This
major upgrade uses high quality Switchcraft jacks, military
spec potentiometers and ARP 2500 style knobs. Requires
the CMS power supply upgrade.