Synth Syntax: Demystifying ‘Paraphonic’
Novation’s Circuit Mono Station synthesis style comes into focus
Novation’s Circuit Mono Station is by no means the first paraphonic synth. But by embracing ‘paraphony’, we entered a sometimes confusing sub-section of synthesis categorisation. In this article, the makers of Circuit Mono Station join forces with Peter Kirn of Create Digital Music to discuss the paraphony puzzle.
Music makers are no strangers to complex terminology. From semi-parametric EQs and half-normalled patchbays to transformer-isolated DI boxes and back-electret microphones, the jargon that bombards us in the studio can be overwhelming. But these words play a vital role in distinguishing one type of ‘thing’ from another, so it should come as no surprise that the complicated world of synthesis has plenty of advanced vocab.
And so we turn to the topic of this piece: the sub-section of phraseology that refers to the number of sounds a synth is capable of creating at any one time. The best known and easiest-to-understand terms in this realm are ‘monophonic’ and ‘polyphonic’, which describe a synth’s ability to play just one voice (monophonic) or multiple voices (polyphonic) at once. A voice is an oscillator or a group of oscillators with an independent filter, amplifier, and/or and amp envelope. (This definition of the ‘voice architecture’ is very important, as you’ll discover.)
Additional complexity arises when you look at the number of oscillators in each voice. Oscillators are the raw tone generators that create the waveforms at the very start of the synthesis process, and they can usually be tuned independently, normally using semitones and cents for coarse and fine tuning respectively. For example, in the case of Bass Station II, a monosynth, there are two oscillators that can create a dual-tone voice, where the pitches of the oscillators move by the same amount in relation to the key played. (e.g. with Osc1 tuned to ‘0’ and Osc2 tuned to +5, you will hear the fifth interval above every key you play.) But despite this ability to play two different pitches, they can’t be individually played or sequenced.
Now, this is where it gets deeper. In some single-voice architectures, it is possible to control the pitches of the different oscillators independently. This behaviour is called ‘paraphony’, and it’s been confusing synthesists — and marketing departments — for decades.
Circuit Mono Station is paraphonic, because you can sequence each of the two oscillators independently. The oscillators share one VCA and envelope, and one filter stage, so although the two oscillators can play different pitches, they can only both be heard when the VCA is triggered.*
A hand-drawn block diagram showing Circuit Mono Station’s paraphonic mode. Note that both oscillators are routed through the same voice architecture. (Image: Paul Whittington)
In Create Digital Music’s first write-up of Circuit Mono Station, Peter Kirn closes the piece with a precise definition of the term: “Synths that have separately controllable oscillators, routed through a common voice architecture (filter/amplitude) are generally called paraphonic. That’s the term Novation use. In this case, you can independently control the pitch of two oscillators at once, via the Circuit Mono Station’s sequencer. But there’s only one amplitude envelope and filter through which they can be routed, so they aren’t truly independent voices — just independent oscillators.”
Novation’s Paul Whittington confirms this: “Circuit Mono Station is a paraphonic monosynth: it has independently controllable oscillators but just one voice architecture. Each oscillator is controlled by its own sequencer, and you have independent control over glide rate, gate length and pattern behaviour.”
For deeper reading, Vintagesynth.com’s Glossary, backs this up, and there’s a reference to paraphony in this article from Gordon Reid’s epic Synth Secrets series in Sound On Sound. The Wikipedia entry for paraphony states that a paraphonic synth’s voices fall short of true polyphony “since they share at least one common element”. And it’s this ‘common element’ clause that lies at the heart of the paraphonic definition; regardless of how many independent oscillators you have, if they share a common amp, filter or envelope generator, it’s paraphonic.
At this point, I’m going to introduce another term — duophonic — which comes up often in the discussions around Circuit Mono Station. The words ‘duo’ (two) and ‘phonic’ (voice) are from Latin and Greek etymologies respectively, but there is not a majority consensus in the synth community about what exactly ‘duophonic’ means in relation to a synth. Some side with the Latin and Greeks, and consider the term to mean a two-voice synth, with dual, independent, voice architectures — in other words, a ‘truly polyphonic’ synth with two voices. But as Create Digital Music founder Peter Kirn points out, “How many two-voice polyphonic synths are there out there even? I can’t think of one!” Kirn, along with plenty of other seasoned synth heads consider duophony to be a sub-category of paraphony, and that ‘duophonic’ adequately describes the limitation of being able to play just two tones at once (and not more) in a paraphonic voice architecture.
“Duophonic means a paraphonic instrument that’s capable of playing two pitches,” says Peter Kirn, who conducted an informal poll of fellow tech types. “There’s a pretty compelling historical timeline to back that up,” Kirn continues, referring to synths like the ARP Odyssey, released in 1972, the duophonic nature of which was extolled in the promotional literature of the day. More recently, Moog’s Sub 37, launched in 2014 as a “paraphonic analog synthesizer”, has a button marked ‘duo’ to engage the synth’s two-oscillator paraphonic mode.
It seems that terminology has been misused since since the ’70s, though. Early magazine advertisements for the ARP Odyssey label it ‘two-voice’ and even ‘polyphonic’ — in all-caps! Neither of these terms are technically correct, if you stick rigidly to the definition that a ‘voice’ needs its own independent filter, amp and envelope generator.
As for the naming of Circuit Mono Station, long-serving Novation Hardware Engineer Nick Bookman recalls a discussion with designer Chris Huggett. “We were going to call it duophonic at one point, but we came to the conclusion that duophonic might imply that it has two independent voices, which Circuit Mono Station does not.” Novation Product Designer Alex Lucas continues, “I remember being corrected after calling it duophonic, so we went through the thought process and felt that paraphonic was the best term for it.” Paul Whittington adds, “in some people’s eyes, Circuit Mono Station is duophonic — depending on how you interpret that term. But because of this potential for confusion, we chose to use paraphonic for Circuit Mono Station, because it’s the one term with an overwhelming consensus on its definition.”
But though paraphonic accurately describes Circuit Mono Station, Peter Kirn finds the term obscure. “The problem with paraphonic is that there’s nothing legible about that word at all. The benefit of using duophonic over paraphonic is that everyone knows what ‘duo’ means, so at least the ‘two’ is readable there. If you’ve never seen the word ‘paraphonic’ before, the only thing that you can derive from it is that ‘phonic’ refers to ‘sound’. And that’s not helpful with a synthesizer. Honestly, most of the fairly serious synth market don’t know what these terms mean, and there aren’t many people who know the overall history of keyboard design, or would even care about this level of pedantry! I think that the average synthesist would say ‘just because something has more notes doesn’t mean more value’. It’s really about how do you as a musician relate to the instrument. How you control the sounds and the pitches.”
The ARP Odyssey — a paraphonic synth— was proudly labelled ‘Polyphonic’ in the advertisements of the day. Clearly there has been confusion around synth terminology for some time! (Image: retrosynthads.blogspot.com.)
And here lies the key. Rather than getting caught up on the verbiage the real question should be ‘does Circuit Mono Station work for me?’ The answer is, hopefully, yes. Regardless of what you call it, Circuit Mono Station is exceedingly fun to use, quick to engage with, and capable of some unpredictable results. In the words of Nick Bookman “It’s a beast of a machine!”
*In our design we have a setting to determine how the VCA will be triggered. The ‘Paraphonic’ mode button (Shift + Scales) on the left does not turn Paraphony on and off as the synth engine is always Paraphonic; what it does is allow OSC 1 to exclusively trigger the VCA, or allow the VCA to be triggered by either oscillator. This is set to ‘mode 1’ (off) by default meaning that OSC 2 can only be heard when OSC 1 triggers the VCA. In ‘mode 2’ (on), either oscillator track in the sequencer can be programmed and played to trigger the VCA.
Words: Chris Mayes-Wright