Moog Opus 3

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"The MOOG OPUS3 consists of three 'fully polyphonic' voice sections - STRINGS, ORGAN & BRASS, as well as an overall voice modulation section, an overall simple amplitude envelope and STEREO mixer output section.

The STRINGS section allows you to dial-in either 16' or 8' pitched strings, with the ability to mix both together. This is routed through a separate filter which is switchable through Lowpass, Bandpass and Highpass settings, which is quite unusual on a Moog synth. Standard Resonance and Cut-Off controls allow you to change the strings from smooth moog sounding strings all the way to buzzy Jupiter 8 sounding strings. One thing to note here is the legends, as the filter Cut-Off is marked up as 'FREQ' and the filter is marked up as 'EQUALIZATION" both incorrect and a departure from Moogs normal FILTER and EMPHASIS.

The ORGAN section comprises a very simple array of flute footage's including 16', 8', 4', 2', 1' (even stops), plus an overall tone control. Not much good on it's own but mixed in with the Strings and Brass it adds a certain amount of weight to the sound... also it can be effected which brings the simple organ section into a class of it's own - more on that later.

The BRASS section comprises switchable 16, 8 and 4 pitched voices (only one pitch at a time) plus a selectable preset filter and envelope or the ability to routing through a separate standalone filter section. With the Brass filter switched to PRESET you get the usual 'blurp' synth brass sound but switching in the filter you have full standard synth controls including FILTER Cut-Off (CF) and Resonance (EMPHASIS) and filter envelope controls including ATTACK, DECAY & SUSTAIN. The Filter envelope RELEASE is controlled via a toggle switch, so it's either on, and it matches the same setting amount as the DECAY slider or it's off, emulating a simple organ envelope which stops on key off. Lastly there's an 'amount to filter' slider which MOOG call CONTOUR AMOUNT... Contour being Moogs name for ENVELOPE.

So here's the magical bit, and the functions that really set the tone of the OPUS3 apart from similar combi units from Crumar & ARP etc (IMHO). The STRINGS section can be routed through a very nice CHORUS unit with controls for effects depth, rate and delay... this effects unit really makes the strings sound vintage and lush and the ability to delay the effect adds a lot to live playing.

Now, in between the STRINGS and ORGAN sections is a horizontal slider which allows you to either route the STRINGS to the chorus unit or the ORGAN to the chorus unit (or a mix of both)... this allows you to then experiment with putting the ORGAN through the chorus... on top of that, between the ORGAN section and the BRASS section there's a similar slider which allows you to put the ORGAN through the separate standalone FILTER... put both sliders to the ORGAN section and you effectively have an additive synth, allowing you to dial-in the tone footage, put them through a filter and envelope and add chorus to fatten the sound. Quite a unique feature and one that can produce some real phat moog synthesizer sounds out of what is basically a combi organ!

All voice sections are put through an amplitude envelope which Moog call an ARTICULATOR... this is basically a simple ATTACK and RELEASE envelope with the ability to either have each note cut off sharply when a new note is played or have the sound sustain through the new notes, this is then routed to the MIXER section where you can control the output volumes of the 3 voice sections and pan them in a stereo mix.

Lastly there's the modulation section. Again this has controls for Amount, Rate and Delay and you can modulate either the filter or the pitch of the voices... which MOOG call FM but I wouldn't call it FM modulation... perhaps at the very fastest setting you'll get some clang?

And the sound... classic retro, sweeping lush strings, rasping brasses and full on organ tiones. All fully polyphonic but surprisingly very Moogy in sound... great live as this thing once warmed up (30 minutes) is very stable. There's much that can be done with this unit... phat moog bass lines, squelchy funk lead lines and rythmic drones with the Modulation section... not to be considered a boring combi organ but a full-on polyphonic Moog synth."