Vintage Synth Repair

At 16:26 Uhr +0900 08.09.2009, Daniel Forro wrote:
> t looks really like CP3A, just that four jack "Multiple" is not
> there...

Well, it certainly is visible in the 1968 modular pictures and in the 1974
pictures for the Moog 35 and 55 (just not for the 15).

http://machines.hyperreal.org/manufacturers/Moog/Modular/info/moog.15.txt

gives this description:

" The 15 has:
    
     (1) 921A Oscillator Driver
     (2) 921B VCO
     (1) 923 Random Noise/Filter
     (1) 921 VCO
     (2) 911 Envelope Generator
     (2) 902 VCA
     (1) 904A VC Lowpass Filter
     (1) 907A Fixed Filter Bank (optional, added cost)
     (1) 995 Atenuators Panel
     (1) 4-input Mixer with Multiples
     (1) Reversible Attenuator
     (1) CV/Trigger Output Panel
    
     The last three items were not standard Moog modules, they are specific
     to the 15 (the bottom row, below the VCO's). Inside is a power supply.
"

So the module in question is the "4-input Mixer with Multiples". I've found
mentioning of a CP-3 module without switches in the wikipedia.

It appears there have been various modules with similar functionality.

"CP" seems to mean "Console Panel".

The bottom panel in the Moog 15 and Moog 10 seems to have been built as a
single unit, containing the 4-input mixer, an attenuator the CV/Trig
interface and the Power Supply; the panels for the Moog 10 and 15 differ
slightly (as far as I can deduct from photos).

The CP-3A seems to have been the one used in the Moog 35 and 55; this one
contains the additional 4-way multiple in the mixer and the switch section
to the left.

There seems to be another variant used in the 3P; this one looks almost
like the CP-3A (including the switch section) but with a switch instead of
the "multiple" section in the mixer.

-- 
Malte Rogacki gacki@... 
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