This is a collection of modifications for a Realistic Moog MG-1 to add MIDI control, filter input, and
other improvements. The MIDI input allows the MG-1 to be played or sequenced
externally, freeing your hands to control the MG1 in real-time. The
filter input accepts line level input which can be driven to distortion
at high levels. The routing gets interesting when you combine MIDI
control with filter input - you can send the audio and MIDI output from
a MIDI synth or computer to the MG1. With keyboard tracking set to full,
the VCF frequency tracks the MIDI CV, allowing control of the filter
cutoff as well.
These modifications transform the existing MG-1 into a responsive and
MIDI-controllable vintage Moog synthesizer.
- Notes - CV/Gate
- CV/Gate (From MIDI or Keyboard) Select switch (left of keyboard)
External audio input to filter
- Line-level audio can be filtered though the 24-dB Moog VCF
1/4" Audio jacks for input and output
- Audio is routed through the pre-existing but unused pitch and
trigger jacks to preserve the MG-1 aesthetics.
Improved gate response
- Improves the rate consecutive-notes can be played on the internal
Multitrigger & continuous glide
Debugging connections before final install
- Adds Moog-style low note priority and retrigger - the gate
retriggers when an additional higher note is played and when the
higher note is released
- The glide continues to the note played even after the note
is released. Normally, the pitch stops gliding when the note is
released, commonly off-pitch between notes.
Octave pitch drop
- This modification allows the MG1 to cover the octave essential for
bass notes in tracks.
- VCO 2 has been modified and now has a pulse width of 50% (from a
thin-sounding 10% pulse width) - both oscillators now have very rich
sounding 50% pulse width square waves
Sticky black foam removal
- Remove the sticky black foam from your MG-1. Originally, I
think the foam acted as a 'blanket' between the body and pcb, but
over time the foam disintegrates into a thick almost
tar-like substance. It's best to remove the foam before it