Moog Prodigy modifications

Analog User Modifications:

Moog Prodigy

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FREE Do It Yourself Special:

Add CV/Gate and Audio Input Jacks to the Moog Prodigy!

Most Moog Prodigy synthesizers have no interface whatsoever. Only the very few last Prodigies made had CV, gate, and audio input jacks. The following plans describe a method of installing the jacks yourself, if you have a little experience with electronic repair and the soldering of wires and circuit boards. If not, these plans will allow a professional repair shop to add the analog interface jacks for you. It is best to download these diagrams and print them out on paper to look at while working on the instrument and make notes and check off the steps as you go. All repairs and modifications made to your instruments will be done at your own risk and Synhouse Multimedia Corporation assumes no liability for personal injury caused or damage to equipment or loss of use caused directly or indirectly by the use of these plans. If in doubt, don't do it!

Brief instructions (diagrams follow at bottom of page):

1) Two 1/4" mono phone jacks with normally-closed SPST switches are required for the CV/gate jacks. A normal mono jack such as the type found on any electric guitar will work for the audio input jack.

2) This mod reroutes the local keyboard signals to the jacks to be installed on the rear panel. The switch built into the jacks will route the CV/gate signals back into the internal synthesizer voice when no plugs are inserted into the jacks. When 1/4" cables are plugged in, the keyboard signal is interrupted and replaced by the external signals, such as the signals coming from another synthesizer such as an ARP, Roland, etc..

3) The audio input jack routes any line level signal through the filter of the Prodigy. The sound of the normal oscillators are not interrupted.

4) Both the CV and gate jacks require cutting traces on the PC board to insert and extract the correct signals for this mod.

5) See pictures provided for exact cutting and soldering points.

6) Extreme caution should be taken while working on the Moog Prodigy. The unit should be unplugged while open and even then, the power supply may pose some electric shock hazard due to residual voltage in the power supply.

7) Examine all connections and leads for possible short circuits before reassembling chassis. The Moog Prodigy was often poorly made and inspected. Some leads of resistors and capacitors were never properly trimmed at the factory and may cause a short circuit and damage some ICs due to the fact that some leads are long enough to touch other adjacent leads. Work carefully and inspect carefully.

8) This modification should take between two and five hours to complete.

9) As an alternative, MIDI can be added to any Moog Prodigy much more quickly and easily than CV/gate jacks by installing the Synhouse MIDIJACK. This allows connecting to any computer sequencer or modern MIDI keyboard with only a single cable, and is most likely more useful nowadays than CV/gate control. The MIDIJACK can be installed in about 20-30 minutes for a Moog Prodigy with factory CV/gate jacks, and about one to two hours for an earlier model without the analog jacks. The audio input may still be desirable and may be installed by itself in conjunction with the MIDIJACK.