Moog Mavis Analog Synth Review

Paperback-sized analog for desktop or Eurorack (in which case it covers lots of ground)

The Moog Mavis is a direct descendant of the company’s Mother 32, and before that the Werkstatt – the first Moog to be offered in kit form.

This too Mavis arrives as a kit, but it’s not a difficult one to assemble – there’s no soldering required. You just mount the synth panel in its case and screw on all the patch point nuts, and you’re supplied with patch cables, patch sheets, a small external power supply, and even an instrument sticky label that you can sign as the constructor.

Like the previous instruments, Mavis is a monophonic synth with one true analog oscillator and a single mode filter. But other facilities have been added to the line as time went on. While the Werkstatt needed an add-on to provide minijack patching points, the Mavis has all these included with 24 minijack patch points to the left of the control panel, as well as a micro keyboard and wavefolder.

Wavefolding? Well that’s a new one to the series, taking the range of sounds available beyond that of the standard sawtooth and square. Fold a wave back on itself as it’s generated and you create all sorts of odd, angular waveforms, and sweeping this control as a sound plays creates new textures that you may not expect from a small monophonic instrument.

Another surprise is the physical size of the Mavis. With a small external power supply (no USB power or battery option) it’s no larger than a (short) paperback novel, and half of that comprises the plastic case. A semi-transparent “deck saver” lid is also provided.

Remove the Mavis from its case and what’s left behind is… nothing. The case has no input, outputs, or anything – every connection is on the top panel.

That opens the Mavis to being readily Eurorack-mounted, which is very easy to do. Many musicians experimented with Eurorack conversion for the Werkstatt, which was quite an intricate task, but on the Mavis all the work has been done for you.

Eurorackness. Suppose your Mavis is now Eurorack-mounted (it takes up 44HP in width and is secured with just four screws). What facilities does it offer compared to individual Eurorack modules?

Quite a few, in fact. From left to right you’re looking at a patching bay, then an analog oscillator with sawtooth and variable width square waves. Pulse width can be altered and swept by a variable mix of the LFO and the envelope generator output, as can oscillator pitch for vibrato and rising/falling effects. The analog filter (lowpass only) benefits from the same variable mix of modulation in positive or negative directions.

So that’s the equivalent of three modules so far. The VCA is inaccessible other than by a master Volume control (though it has a patch point In for external voltages), but it can be bypassed, so the Mavis can make constantly droning sounds – something not available even on the classic MiniMoog.

In another extension of the MiniMoog design, the envelope has a full four independent stages for Attack, Decay, Sustain and Release. And the LFO can be varied from a triangle wave to a square wave.

The micro keyboard covers a full octave (and has voltage and gate outputs so it can control other analog instruments), and there’s a variable Glide control. There’s also a control to adjust the keyboard span, alongside a mini preset, adjustable with the small screwdriver provided to get a perfect one octave per volt.

Finally, that Wavefolding parameter, classed under Utilities alongside a voltage source and attenuator, each accessible using the patch bay.

So that’s the equivalent of half a dozen Eurorack modules at least. At a typical sale price of £250-270 in the UK ($300 in the USA) makes the Mavis a pretty good value for money.

It doesn’t match width with the company’s DFAM and other Eurorack-mountable instruments, but is quite capable of being mounted within Moog’s own racks or those from other makers. 

Sonic surprises. The Mavis layout appears simplistic, but in the combinations of various settings and patching points it can become quite versatile.

For example, there are patch points for Sample & Hold from the VCO, and Gates from the LFO. From an external source (or by patching the internal LFO, if you’re not depending on it for something else) the Wave Fold setting can be controlled, and this can be a source of unexpected, digital-like textures.

The Attenuator and the “One Level” parameter (in fact mixable between two different voltage levels) become flexible controllers of a range of sonic parameters, on board or within any external modular system.

And this is where the open design of the Mavis pays off, since it can work equally happily as an independent desktop synth, interfaced to an external modular system, or mounted within such a system to take over any number of the jobs we’ve mentioned. When you’re not using the Mavis as an independent voice, you can rely on it for extra modulation, filtering, envelope shaping, envelope triggering, keyboard control, and much more.

With regard to limitations compared to other models, the Mavis doesn’t have MIDI, memories, octave-switching (just a widely varying pitch control), white noise, or built-in effects. So it’s perhaps more an instrument for spontaneous improvisation than for taking part in complex compositions that need to be reproduced.

Not that it’s difficult to try to reproduce particular settings, using patch sheets if you wish. The controls are widely spaced and easily accessible, though we’re bound to see some users trying to add plusher knobs, which would almost certainly obscure the panel labelling.

On the Moog Music site you can hear various sonic demos of the Mavis and watch videos of several artists improvising with the module (or “Analog Synthesizer Voice” as it’s labelled). You’ll hear recognizable analog sounds, but also some more unusual textures created by patching the LFO to wavefolding, or patching external sources – maybe envelopes, random sample-and-hold outputs, or additional LFOs – to wavefolding, oscillator pulse width, filter cutoff, and so on.

Mavis is not just a way in to modular for the beginner, but a valuable add-on to any existing modular system, or a good friend for similar patchable desktop modules, drum machines, and effects.