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"The M3X is a hand-built, drift-free, MIDI-controlled, rack-mount analog synthesizer from Scottish synth designer Ken MacBeth.
The M3X is similar to the Minimoog in that it features three oscillators and a transistor-ladder filter for warm analog sounds in a simple, streamlined package, although the M3X goes beyond the original Moog.

The M3X has been designed to operate via MIDI or traditional 1V/Octave control voltage input and output, as well as the standard S Trig interface as used by many analog systems.
The M3X has three dedicated oscillators, each with five waveform types and user selectable destinations including cross-modulation capabilities.
In addition to the oscillators, there is a noise generator and an external audio input amp for processing other synths or sound sources.
The filter section is a transistor-ladder type similar to that used in the Moog synthesizers and sounds totally warm and at times harsh (a good harsh).
It offers 24dB/oct low-pass filtering with controls for frequency cutoff, resonance, envelope amount, attack, decay/release and sustain.
The VCA amplifier also features attack, decay/release and sustain controls.
The Mixer section offers volume controls for each of the oscillators, noise generator and external audio input plus a master volume.
The digital menu system provides access to the MIDI, LFO, Portamento, and various tuning and scaling parameters.
Absolutely simple, hands-on and easy to understand but full of big beefy analog sounds."