Duophony / 1 note per oscillator in Moogs

[XAXAU]

I played around with my Minitaur with one oscillator octaved up and since there is a note restriction at C4 i experienced the massive sound of duophony or rather one oscillator per note. When playing C3 I´m hearing C3 on one oscillator and C4 on the other since it´s octaved. But when for example playing G3 it´s not G3 and G4 but G3 and C4, a perfect fifth, it sounded ENOURMOUS. and the other usual intervals sounded just as good.

So, why is it that "duophony" or one oscillator per note isn´t available in Moogs? I own a Minitaur, a Slim Phatty and a Sub Phatty, and this function would improve the sound capabilities immensely!!!

Is there a technical limitation that prohibits this or what?

Amos, I need you!

[unfiltered37]

I haven't played a minitaur so i am not exactly sure what you are referencing, but the concept of detuning oscillators is nothing new, and in fact I use it all the time on my vintage mini. Technically speaking, it is still monophony when playing two parallel melodies tuned to an interval. But yes, it is very cool because even though you have an interval, say a perfect fifth, you will not really hear that interval when playing melodically. Meaning I can tune three oscillators to a major triad, and still play a minor or whatever scale and the major intervals are not really heard as harmonic, but rather still monophonic minor scale. The intervals are also much more syncronized than a normal polyphonic keyboard, because the voltages are the same for all oscillators, meaning unequal temperament, and more perfect intervals. Like tuning a piano so one musical key sounds better than all the rest.

I don't know what principle of harmony or psychoacoustics make this happen, but when playing parallel you don't really hear the intervals as "chords" when moving the chord up and down the chromatic scale. Guitar players will do this sometimes, hold one chord pattern and play it up and down the neck melodically. You hear the color of the chord, but it doesn't function like a chord.

I exploit this in my playing a lot, and it is one thing unique about multiple oscillator synths. I do a lot of modal improvisation, playing over a monotonic bass line, and it can really add something unique to the sound. The crazy thing is you can even make non-musical intervals among the oscillators, yet still get a patch that sounds musical. The interactions of different waveforms and their harmonics with those of other oscillators can make for some very interesting and musical patches.

I have actually contemplated getting a bunch of modular oscillators, like 7-10 of them with a huge mixer with all different waveforms and tunings. I have tried recording different oscillators tuned to different notes and with different waveforms unfiltered, then mixing them down in different proportions and then filtering them, with very cool results.

[eXode]

I think that the OP is speaking about duophony as i.e. the ARP Odyssey offered.

There's actually a very small theoretical change to add such duophony to any monophonic instrument with two oscillators. If my memory serves me right, ARP achieved duophony on the Odyssey by having one oscillator set to highest note priority, and the other to lowest note priority. This means that when you play a two finger chord, one oscillator will play the lower note, and the other the higher note.

[unfiltered37]

Is he talking about

I think that the OP is speaking about duophony as i.e. the ARP Odyssey offered.

There's actually a very small theoretical change to add such duophony to any monophonic instrument with two oscillators. If my memory serves me right, ARP achieved duophony on the Odyssey by having one oscillator set to highest note priority, and the other to lowest note priority. This means that when you play a two finger chord, one oscillator will play the lower note, and the other the higher note.

That might have been cool back before polys, but it doesn't make much sense for a modern monophonic synth. If you have multiple synths, you can achieve the same thing. A firmware option would not be possible because the oscillators all respond to the note information the same.

[eXode]

That might have been cool back before polys, but it doesn't make much sense for a modern monophonic synth. If you have multiple synths, you can achieve the same thing. A firmware option would not be possible because the oscillators all respond to the note information the same.

Sorry but what you're proposing is kind of silly. Buy another SYNTH for that? The firmware option might well be possible depending on how the instruments were designed to start with. Afaik the note priority settings are already there, it's the question if it's possible to split the priority between two oscillators.

I'm questioning if you fully understood my explanation of how the ARP Odyssey does it, because your reply quite frankly doesn't make much sense. Your statement about "duophonic might have been cool before polys" is about as silly as claiming that "monophonic might have been cool before polys".

The OP asked if there's a technical limitation to why the Moog doesn't offer duophony and my reply is that it's at most a limitation in how note priority was implemented but it's not impossible nor difficult to do, theoretically.

[thealien666]

The reason why duophony isn't possible with Moogs, except in old modular ones, is that the pitch CV is common to all oscillators by design.
Sure you can select different octaves for each ones, but the basic key CV is the same. The octave switch only adds an offset locally in the oscillator circuit.

Offering the possibility of duophony, ie controlling the pitch of each oscillators independently with two keyboards (on two separate MIDI channels for example), would require a completely independent Pitch Control Voltage for each, and therefore a completely different electronic circuit design.

Duophony is much more easily achieved with a modular system. Unless the synthesizer itself was design with that possibility in mind from the get go. Like a ARP Odyssey, Roland SH-7, or Korg 800DV (and possibly a few others...).

On the Minitaur, the "leveling" of the maximum CV for pitch creates a funny situation where the highest possible pitch obtainable (C4) remains playing, despite trying to obtain a higher pitch like a D4 (by playing a D3 and having the octave switch that should have it play a D4).

However, you can still get some sort of fixed duophony, by selecting an interval between the two oscillators, like a third or a fifth and others.
On a Minimoog with 3 oscillators, you can even play "preset 3 notes chords" ! Would that be called Triphony (or rather Triphoney) ?

[unfiltered37]

He already has multiple synths. When the Odyssey was made, synths were super expensive, so duophony was not possible unless you were loaded, so the odyssey was novel in that it could do two notes at a time. But today you can get an entire polyphonic phatty setup for the same price as a monosynth back then, so duophony is nothing special.

I am not saying it wouldn't be cool, but it is just not practical or useful because of midi and cheap multiple oscillator monosynths.

[thealien666]

You're right. Heck, with MIDI's 16 channels, one could even create a 16 voices polyphonic monster synth from 16...Korg Volca Keys for less than the price of a DSI Prophet 12 !

[XAXAU]

I think that the OP is speaking about duophony as i.e. the ARP Odyssey offered.

There's actually a very small theoretical change to add such duophony to any monophonic instrument with two oscillators. If my memory serves me right, ARP achieved duophony on the Odyssey by having one oscillator set to highest note priority, and the other to lowest note priority. This means that when you play a two finger chord, one oscillator will play the lower note, and the other the higher note.

This is exactly what I´m talking about! It´s also such a shame that Moog won´t allow us to do polychaining between different Moog synths! With the synths I have I could be making three note chords or six note chords with duophony!

Afaik the note priority settings are already there, it's the question if it's possible to split the priority between two oscillators.

I really hope so!

[eXode]

This is exactly what I´m talking about! It´s also such a shame that Moog won´t allow us to do polychaining between different Moog synths! With the synths I have I could be making three note chords or six note chords with duophony!

For synths with CV/GATE you could get a "polyphonic" MIDI to CV/GATE interface to get that feature. One example is the Kenton PRO 2000 Mk II that offers up to four voices of polyphony through CV/GATE.

[XAXAU]

The reason why duophony isn't possible with Moogs, except in old modular ones, is that the pitch CV is common to all oscillators by design.
Sure you can select different octaves for each ones, but the basic key CV is the same. The octave switch only adds an offset locally in the oscillator circuit.

Damn! Well, it sounds like it should have been so simple to implement? The Moog oscillators are so chunky that it´s a shame not having duophony or triophon(e)y!

[XAXAU]

For synths with CV/GATE you could get a "polyphonic" MIDI to CV/GATE interface to get that feature. One example is the Kenton PRO 2000 Mk II that offers up to four voices of polyphony through CV/GATE.

I was just looking at that! So I´m a bit daft, are you saying I could "polychain" my Moog synths?

[eXode]

For synths with CV/GATE you could get a "polyphonic" MIDI to CV/GATE interface to get that feature. One example is the Kenton PRO 2000 Mk II that offers up to four voices of polyphony through CV/GATE.

I was just looking at that! So I´m a bit daft, are you saying I could "polychain" my Moog synths?

Yes, but you'd need to use CV/GATE to do it, so basically only control over Gate and Note (pitch). Also I don't know how the voice mode works exactly, so I don't know how predictable it is (i.e. the result might be random, which synths plays which note).

[XAXAU]

For synths with CV/GATE you could get a "polyphonic" MIDI to CV/GATE interface to get that feature. One example is the Kenton PRO 2000 Mk II that offers up to four voices of polyphony through CV/GATE.

I was just looking at that! So I´m a bit daft, are you saying I could "polychain" my Moog synths?

Yes, but you'd need to use CV/GATE to do it, so basically only control over Gate and Note (pitch). Also I don't know how the voice mode works exactly, so I don't know how predictable it is (i.e. the result might be random, which synths plays which note).

Alright I´m gonna download the manual for it and check it out. Was thinking of getting a row of euros for effects, modulation and stuff and I know there is a slick module by Mutable Instruments coming out soon that can do those kinds of tricks! http://www.modulargrid.net/e/mutable-instruments-yarns

[XAXAU]

For synths with CV/GATE you could get a "polyphonic" MIDI to CV/GATE interface to get that feature. One example is the Kenton PRO 2000 Mk II that offers up to four voices of polyphony through CV/GATE.

I was just looking at that! So I´m a bit daft, are you saying I could "polychain" my Moog synths?

Yes, but you'd need to use CV/GATE to do it, so basically only control over Gate and Note (pitch). Also I don't know how the voice mode works exactly, so I don't know how predictable it is (i.e. the result might be random, which synths plays which note).

Alright I´m gonna download the manual for it and check it out. Even if the voice allocation is random it could be cool! Was thinking of getting a row of euros for effects, modulation and stuff and I know there is a slick module by Mutable Instruments coming out soon that can do those kinds of tricks! http://www.modulargrid.net/e/mutable-instruments-yarns