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Help Understanding Paraphonic Mode

ARNK

Help Understanding Paraphonic Mode
« on: October 10, 2017, 09:45:08 PM »
When the PRO 2 is set to Paraphonic mode, and you have oscillators 1-4 set to Sawtooth at 71 volume.

What should I expect to hear pressing one key, the same key, four times in a row? My understanding was that I would hear oscillators 1 on the first hit, 2 on the second hit, 3 on the third, and so on. Is this assumption correct?

Because when I attempt this, it only appears to cycle between oscillators 1 and 4, so back and forth between 1 and 4 without oscillators 2 and 3. I checked this by changing oscillator shape on to Super Saw and 4 to Muted. 2 and 3 to Sawtooth, and as I play the same note repeatedly, it jumps only between the Super Saw and Muted oscillators.

A bit confused as to why that might be happening. Thanks in advance.

Re: Help Understanding Paraphonic Mode
« Reply #1 on: October 11, 2017, 03:51:54 AM »
Your assumption of how the paraphonic mode should work is correct. With each key stroke, the cycle between oscilltors 1-4 is advanced one step. So the behaviour you described is unusual. Even if oscillators 2 and 3 were set to a zero output level, you should hear nothing twice when you hit the keys.
Ableton Live 9 Suite & Push 2 (macOS) | Arturia BeatStep Pro | DSI Pro 2 | KMI QuNexus | Korg Volca Beats | Moog MF-104M Analog Delay | Moog Minitaur | Moog Model 15 App | Moog Sub 37 Tribute Edition | Sequential Prophet-6

ARNK

Re: Help Understanding Paraphonic Mode
« Reply #2 on: October 14, 2017, 08:18:59 AM »
Your assumption of how the paraphonic mode should work is correct. With each key stroke, the cycle between oscilltors 1-4 is advanced one step. So the behaviour you described is unusual. Even if oscillators 2 and 3 were set to a zero output level, you should hear nothing twice when you hit the keys.

Gotcha. Oi, have a ticket into support.

Re: Help Understanding Paraphonic Mode
« Reply #3 on: October 14, 2017, 01:32:20 PM »
Check your filter settings as well.

All four OSCs plus the subosc live on the same DSP IIRC, so there's probably only two DAC channels (and one IC) to feed each of the two filters (when set to parallel, OSC 1+2 go to filter 1, OSC 3+4 go to filter 2); if you have OSC 1 and OSC 4, even when split, then I doubt it's a hardware problem.

In fact–checking this on mine–it's likely that you're hearing 2-3-4-1, with 3-4 set as silent.
« Last Edit: October 14, 2017, 01:41:17 PM by DavidDever »
Sequential / DSI / Pioneer stuff: Prophet-12 desktop, Pro-2, AS-1, Prophet-600 Gligli, Prophet 2000

Re: Help Understanding Paraphonic Mode
« Reply #4 on: October 14, 2017, 04:04:00 PM »
sorry - meant Oscillator Split.
Sequential / DSI / Pioneer stuff: Prophet-12 desktop, Pro-2, AS-1, Prophet-600 Gligli, Prophet 2000

ARNK

Re: Help Understanding Paraphonic Mode
« Reply #5 on: October 19, 2017, 09:27:09 PM »
sorry - meant Oscillator Split.

Thanks for your response, but it's definitely still unclear.

If you had a moment, would you mind listing the steps you're taking to reach your conclusion?

Perhaps I'm just not understanding.

So for me, say you have things setup in Paraphonic Mode, with all 4 oscillators set at 100 volume.

1. Osc 1 is a Super Saw
2. Osc 2 is a Sine
3. Osc 3 is a Tines
4. Osc 4 is Gothic

No matter if I have Oscillator Split on/off, Filter 1 or 2 off, I only hear 2 of the 4 oscillators while hitting the C2 key (for example) repeatedly, not all 4 oscillators, each with a wave shape established and a volume level set.

So either I'm not understanding how this should actually work, I have the synth configured incorrect, or hopefully not the case, there's something wrong with the board itself.

Kind regards

Re: Help Understanding Paraphonic Mode
« Reply #6 on: October 19, 2017, 11:57:19 PM »
sorry - meant Oscillator Split.

Thanks for your response, but it's definitely still unclear.

If you had a moment, would you mind listing the steps you're taking to reach your conclusion?

Perhaps I'm just not understanding.

So for me, say you have things setup in Paraphonic Mode, with all 4 oscillators set at 100 volume.

1. Osc 1 is a Super Saw
2. Osc 2 is a Sine
3. Osc 3 is a Tines
4. Osc 4 is Gothic

No matter if I have Oscillator Split on/off, Filter 1 or 2 off, I only hear 2 of the 4 oscillators while hitting the C2 key (for example) repeatedly, not all 4 oscillators, each with a wave shape established and a volume level set.

So either I'm not understanding how this should actually work, I have the synth configured incorrect, or hopefully not the case, there's something wrong with the board itself.

Kind regards

That still doesn't sound right. To be on the safe side though: Initiate the basic program (hold down the left LATCH button and press HOLD), go to the MISC PARAMS menu to activate paraphonic mode, set the volume level for each oscillator to 100, and finally select a waveform for each oscillator. Do nothing else. If the problem persists, you should get in touch with the technical support at support@davesmithinstruments.com.
Ableton Live 9 Suite & Push 2 (macOS) | Arturia BeatStep Pro | DSI Pro 2 | KMI QuNexus | Korg Volca Beats | Moog MF-104M Analog Delay | Moog Minitaur | Moog Model 15 App | Moog Sub 37 Tribute Edition | Sequential Prophet-6

Re: Help Understanding Paraphonic Mode
« Reply #7 on: October 20, 2017, 11:29:16 AM »
This could be caused by a MIDI feedback loop. Remove all MIDI/USB cables and see if you get the same results.
Dave Smith Instruments

ARNK

Re: Help Understanding Paraphonic Mode
« Reply #8 on: October 20, 2017, 08:32:11 PM »
Hmm, okay thanks guys. Your comments mirrored supports, before in Global settings #11 - MIDI Out Select was set to USB. When I unplugged both the MIDI cable AND the USB cable, things worked as expected. When I plugged back in the USB chord and the MIDI cable (in MIDI Out) then changed the MIDI Out Select to MIDI it's now working as expected.

I'm not sure why this would be but definitely a step in the right direction. Thanks for your input!

Re: Help Understanding Paraphonic Mode
« Reply #9 on: October 25, 2017, 12:43:04 AM »
Can we go back to the title of this topic and can someone clearly explain the way of working of the paraphonic mode?
I've been playing with my pro2 now several evenings in a row  ;D but still cannot understand the why of the great sounds I get in paraphonic mode.
- paraphonic level at 127 but all OSC levels at 0 and I still get sound. Thought it was the filters but when I change the OSC shape to OFF then it is indeed OFF. So, in paraphonic mode, what is the individual osc level doing?
- what needs to be done to get a paraphonic sound playing a 3-4 notes chord? what is happening under each key? Is each key associated to one osc? if yes, which one goes to which key? random?
- unison / stacking 4 osc under one key: paraphonic level = 0; Key assign = low/high/last note; Correct?

Thx in advance for your explanations  8)
DSI Pro 2 | Moog Sub 37 | Waldorf Blofeld |  Korg Radias x2 | Yamaha Motif ES8 | TC Electronics M350 | Behringer Xenix X1622USB

Re: Help Understanding Paraphonic Mode
« Reply #10 on: October 25, 2017, 01:16:38 AM »
Can we go back to the title of this topic and can someone clearly explain the way of working of the paraphonic mode?
I've been playing with my pro2 now several evenings in a row  ;D but still cannot understand the why of the great sounds I get in paraphonic mode.
- paraphonic level at 127 but all OSC levels at 0 and I still get sound. Thought it was the filters but when I change the OSC shape to OFF then it is indeed OFF. So, in paraphonic mode, what is the individual osc level doing?
- what needs to be done to get a paraphonic sound playing a 3-4 notes chord? what is happening under each key? Is each key associated to one osc? if yes, which one goes to which key? random?
- unison / stacking 4 osc under one key: paraphonic level = 0; Key assign = low/high/last note; Correct?

Thx in advance for your explanations  8)

1. Quad Level overrides individual levels IIRC in paraphonic mode, but you'd have to report back on your findings :)
2. Not sure about key assignment, but I believe that it's round-robin (last- / next-note).
3. Individual levels override Quad Level IIRC, in last- / low- / high-note priority, see #1.

The manual(s) is/are always a good place to start :) though it is truly a point of departure; you will find that you accumulate more understanding as you work within the individual sections over time.
Sequential / DSI / Pioneer stuff: Prophet-12 desktop, Pro-2, AS-1, Prophet-600 Gligli, Prophet 2000

Re: Help Understanding Paraphonic Mode
« Reply #11 on: October 26, 2017, 02:24:29 AM »
With each key stroke, the cycle between oscillators 1-4 is advanced one step.

Can you explain this more?
Didn't find this in the manual but indeed when I play 4 times the same key I get each time a different sound which is very nice when you have some longer releases.
I'd like to understand how come it is cycling, what is behind each sound (OSC 1 to 4 I guess), which Amp envelopes are used for each key stroke (four times the same?), which filter is used for each key stroke (four times the same?).
If I'm playing a 4 note chord at once, what is happening in terms of cycling?
DSI Pro 2 | Moog Sub 37 | Waldorf Blofeld |  Korg Radias x2 | Yamaha Motif ES8 | TC Electronics M350 | Behringer Xenix X1622USB

Re: Help Understanding Paraphonic Mode
« Reply #12 on: October 26, 2017, 03:33:31 AM »
With each key stroke, the cycle between oscillators 1-4 is advanced one step.

Can you explain this more?
Didn't find this in the manual but indeed when I play 4 times the same key I get each time a different sound which is very nice when you have some longer releases.
I'd like to understand how come it is cycling, what is behind each sound (OSC 1 to 4 I guess), which Amp envelopes are used for each key stroke (four times the same?), which filter is used for each key stroke (four times the same?).
If I'm playing a 4 note chord at once, what is happening in terms of cycling?

Each time you hit a key, one of the four oscillators is triggered from 1-4, 2-1, 3-2, or 4-3, depending on how many times you've already hit a note. That's meant by the term cycling.

On the Pro 2, each oscillator is triggered with an envelope set by the VCA shape, as the manual states on page 5. That means that any time you hit a key the VCA behaviour will be the like you would expect it to be on a polyphonic synth. There is still only one VCA on the Pro 2, which is the fundamental difference to a polyphonic synth.

The articulation of the two filters is shared among all oscillators. This will only have an audible effect if you use the filters' enevelope generators to control their behaviour. If you keep holding a note and play other notes on top of that or if you play legato, the filter envelopes won't be retriggered with each new keystroke. For that to be the case, you would need four filters each (four times the LP filter and four times the state variable filter). But on the Pro 2 the filter envelopes will just continue to do whatever you've programmed when you play sustained notes or legato style after an independent keystroke.

On the Pro 2 you can of course split the filters amongst two pairs of oscillators so that oscillators 1 and 2 run through the LP filter and oscillators 3 and 4 run through the state variable filter. In that case the behaviour of the LP filter is shared if you trigger oscillators 1 and 2, just as well as the behaviour of the state variable filter is shared if you trigger oscillators 3 and 4.

It may be helpful to consider what would be necessary for a 4-voice polyphonic mode by contrast. If the Pro 2 was polyphonic to this degree, it would need 4 times as many oscillators, making it a total of 16, four of each filter (four LP filters, four state variable filters), and four individual VCAs. In short: it would need four complete voices so that each keystroke would trigger the complete number of oscillators, an individual filter, and an individual VCA. In this case you would have cycling too. But the important difference is that on a polyphonic synth you cycle through complete voices and not just through the single oscillators each time you hit a key.

The Pro 2 is monophonic in essence, though. So if you play a 4 note chord in paraphonic mode it is as if you would subdivide a monophonic voice by the total number of available oscillators. The number of oscillators sort of creates the illusion of polyphony while the whole signal path still remains monophonic. What this illustrates first and foremost in methodological terms is that oscillators should never be confused with voices. The Pro 2 has four oscillators, but only one voice.
« Last Edit: October 26, 2017, 03:46:15 AM by Paul Dither »
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Re: Help Understanding Paraphonic Mode
« Reply #13 on: October 27, 2017, 01:29:41 AM »
Thx for your explanations Paul. There are still things not fully clear for me.
I know/understand the structure of the Pro2 (I think) and I made a picture we can use to discuss things.
Just tell me if there is something wrong there  :)

What is not clear for me regarding the paraphonic behaviour...

Case1: playing the same note 4 times in a row, I hear 4 different sounds (nice).
- According to your explanation, each key stroke triggers one oscillator as in a cycle. Is it key stroke 1 triggering OSC1 then key stroke 2 OSC2 and so on? Didn't see this explanation in the manual...
What do you mean by 1-4, 2-1, 3-2, 4-3?
- the sound coming from each OSC will follow the same Amp EG shape
- there is an individual Amp EG followed by each key. There are thus 4 Amp EG but one VCA; Correct? What is bringing the 4 Amp EGs? Is it that when you play 4 notes after each other, the first note can still be in sustain or release stage while the next note is still in attack and so on... I think I'm right but asking just to be sure
- the sound coming from each OSC will use the same filter setup except if we use Osc split where we can use filter1 for OSC1 and 2 and filter2 for OSC3 and 4
- if we want to play paraphonic like that (one key at a time) then it is probably advised to have the same patch separately without paraphonic mode but where we can listen and adjust the params of each OSC separately

Case2: playing a chord of 4 notes
- is it also a cycling but that is so fast that one hears only one sound?
- to get a typical pad chord, we should then set the 4 OSC in about the same way but add slight differences between them (slop, detune...) to give the evolving polyphonic chord effect. Correct?
- to go wild, we can set the 4 OSC in different ways and use OSC split on the filter section to tear things apart. Also correct?
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Re: Help Understanding Paraphonic Mode
« Reply #14 on: October 27, 2017, 05:23:06 AM »
What is not clear for me regarding the paraphonic behaviour...

Case1: playing the same note 4 times in a row, I hear 4 different sounds (nice).
- According to your explanation, each key stroke triggers one oscillator as in a cycle. Is it key stroke 1 triggering OSC1 then key stroke 2 OSC2 and so on? Didn't see this explanation in the manual...
What do you mean by 1-4, 2-1, 3-2, 4-3?

If you turn on your Pro 2 and haven't played a note yet, the first keystroke on a paraphonic patch will trigger oscillator 1, the second oscillator 2, and so on. If you have played some notes already on the Pro 2 and then switch to a paraphonic preset, the number of the first oscillator you hear will depend on how many notes you've already played on the Pro 2's keyboard before you switched to the paraphonic preset.

Example: You turn on your Pro 2 and hit the keys 3 times, then you switch to a paraphonic preset. The first time you hit a note on that preset will actually be the forth time you hit a key on the Pro 2 in total ever since you turned it on. Hence, the first oscillator of the paraphonic patch that will be triggered will be oscillator 4. So in this case you'll end up with a cycle from oscillator 4 to oscillator 3 (if you take the moment you selected the paraphonic preset as the starting point of that cycle). That's what I meant by 4-3 or 2-1 and 3-2 respectively.

In summary: The oscillator allocation of a paraphonic preset is always dependend on how many times you've already hit a key.

- the sound coming from each OSC will follow the same Amp EG shape
- there is an individual Amp EG followed by each key. There are thus 4 Amp EG but one VCA; Correct? What is bringing the 4 Amp EGs? Is it that when you play 4 notes after each other, the first note can still be in sustain or release stage while the next note is still in attack and so on... I think I'm right but asking just to be sure

How DSI implemented that each oscillator is triggered by the VCA EG shape that is defined in the VCA section is not explained anywhere. Maybe someone from the DSI crew can chime in to explain what's exactly happening at that stage. As the envelopes are digitally controlled, I assume it's a matter of an oscillator/VCA curve trigger assignment that is coded in the firmware.

What can be said, though, is that the VCA EG shape is triggered per voice, even in paraphonic mode. You have 1 voice and 4 oscillators. Example: Set a long release time for the VCA envelope and then play four notes consecutively (don't hold them or otherwise you won't hear the release stage). All four notes will fade out niceley according the the VCA envelope's release stage. If you then hit a fifth note, you will hear something that resembles a voice stealing effect: the release stage of first note you hit will be rudely cut off. (Strictly speaking, it can't be called voice stealing if one likes to remain coherent with regard to methodologically correct terminology; what is being 'stolen' is one of the four derivatives of the VCA envelope shape that controls how each of the four oscillators is being triggered per voice. True voice stealing would result in all release stages being cut off initially, once you play the fifth note.) If you play a sixth note, the release stage of the second note you hit will be cut off, and so on. In short: A smooth VCA envelope response only works for the length of one cycle, and in terms of circuitry, one cycle equals one voice.

- the sound coming from each OSC will use the same filter setup except if we use Osc split where we can use filter1 for OSC1 and 2 and filter2 for OSC3 and 4

Right. It's like in your diagram.

- if we want to play paraphonic like that (one key at a time) then it is probably advised to have the same patch separately without paraphonic mode but where we can listen and adjust the params of each OSC separately

I'm not quiet sure what you're saying here. If you're implying that you only get true 4-note polyphony by multitracking one monophonic patch four times instead of using a paraphonic patch once, you're correct.

Case2: playing a chord of 4 notes
- is it also a cycling but that is so fast that one hears only one sound?

Technically yes.

- to get a typical pad chord, we should then set the 4 OSC in about the same way but add slight differences between them (slop, detune...) to give the evolving polyphonic chord effect. Correct?

That depends on how you define "a typical pad chord". If you, for example, have a slightly detuned analog poly synth in mind, then your approach is the way to go. A super clean combination (no slop, no detune) of four different oscillator waveforms could be just as typical, although it might sound considerably thinner as a result.

- to go wild, we can set the 4 OSC in different ways and use OSC split on the filter section to tear things apart. Also correct?

Sure. The more differentiating variables you add to the equation, the less homogenic a sound will become. I mean already selecting four entirely different waveshapes for the four oscillators does go beyond what we would usually describe as polyphony (I'm deliberately not using the term "paraphony" here). Because polyphony would be x times one identical voice. But using different sounds per oscillator rather resembles the effect of a quartet (in the case of the Pro 2). So while the Pro 2's paraphonic mode comes with the limitations of a monophonic voice architecture, its possible oscillator settings go actually beyond the common concept of polyphony.
« Last Edit: October 27, 2017, 05:28:57 AM by Paul Dither »
Ableton Live 9 Suite & Push 2 (macOS) | Arturia BeatStep Pro | DSI Pro 2 | KMI QuNexus | Korg Volca Beats | Moog MF-104M Analog Delay | Moog Minitaur | Moog Model 15 App | Moog Sub 37 Tribute Edition | Sequential Prophet-6

Re: Help Understanding Paraphonic Mode
« Reply #15 on: October 28, 2017, 09:58:10 AM »
Got you! Super thanks!
DSI Pro 2 | Moog Sub 37 | Waldorf Blofeld |  Korg Radias x2 | Yamaha Motif ES8 | TC Electronics M350 | Behringer Xenix X1622USB