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How to use just one voice on Basic Path without unison?

How to use just one voice on Basic Path without unison?
« on: May 17, 2020, 03:21:00 PM »
v.1.4.0

When I init a patch (latch -> hold),

From what I see it turns on OSC 1 with a saw and LFO 1 mapped to 'Osc All Freq' with an amount of 0 (but it's sleep modulating the freq and I cannot understand why).

When I play a note, the Prophet 12 in the top right hand corner is indicating that 2 voices are active, where is the second voice coming from? Unison is off, Stacked is off, split is off, but it sounds like 2 saw waves detuned to each other are playing.

Can someone lend me some knowledge?

And why does LFO 1 modulate the frequencies of the oscillators on Basic Patch when the amount is set to 0?

R

Re: How to use just one voice on Basic Path without unison?
« Reply #1 on: May 17, 2020, 03:36:44 PM »
I don't have a P12 myself, so maybe someone else can chime in and correct me on this, but I just looked up the manual for the P12 and it says that OSC1 and 2 are turned on in the basic patch. Could it be that the tuning effect you're hearing is because these two oscillators are slightly out of tune to one another? Try turning off the second OSC, or using Fine Tune to get the oscs as close as you can to one another.

But this doesn't explain why you're seeing two voices on the front panel when you're playing one note. I'd be curious to see what it turns out to be.
« Last Edit: May 17, 2020, 03:40:57 PM by will.taylor »

Re: How to use just one voice on Basic Path without unison?
« Reply #2 on: May 17, 2020, 04:29:12 PM »
I don't have a P12 myself, so maybe someone else can chime in and correct me on this, but I just looked up the manual for the P12 and it says that OSC1 and 2 are turned on in the basic patch. Could it be that the tuning effect you're hearing is because these two oscillators are slightly out of tune to one another? Try turning off the second OSC, or using Fine Tune to get the oscs as close as you can to one another.

But this doesn't explain why you're seeing two voices on the front panel when you're playing one note. I'd be curious to see what it turns out to be.

I thought I removed this post so Iím sorry for the confusion! Turns out that my Daw was sending the midi it received back into the prophet. (which now that I know sounds pretty cool like another way of stacking). Obvious mistake now but I was looking for a solution in the synth not outside it.

I still donít understand why an Lfo at 0 amount is modulating the frequencies though as can be found on init patch

Re: How to use just one voice on Basic Path without unison?
« Reply #3 on: May 18, 2020, 05:22:37 AM »
On my Mopho Keyboard, you can hear a subtle phasing effect on the initialisation patch if you listen closely. This patch is very similar to the one on the Rev 2, just two saw oscs with the filter wide open. I found that Osc 1 was Fine Tuned to -1, and Osc 2 was Fine Tuned to +1. Even when setting them both to zero, the phasing is still present, though to a lesser extent. I'm guessing this is just because of slight variances in the two oscillators.

Could it be that this phasing is what you're hearing?

It seems unlikely on an Init Patch, but maybe could there be something assigned to modulate the LFO 1 Amount such as the mod wheel or aftertouch? You could also try changing the mod destination of the LFO to something else, such as Cutoff, in order to see if it is definitely modulating at a zero amount.

Re: How to use just one voice on Basic Path without unison?
« Reply #4 on: May 18, 2020, 05:28:56 AM »
Here's a recording of the phasing I was describing in my last post. You can also see it in the waveform generated by my DAW.

Re: How to use just one voice on Basic Path without unison?
« Reply #5 on: May 18, 2020, 01:07:32 PM »
could there be something assigned to modulate the LFO 1 Amount such as the mod wheel or aftertouch?

I'm embarrassed, it was the mod wheel. First real synth here, not used to checking these things. I appreciate the lookout.

Re: How to use just one voice on Basic Path without unison?
« Reply #6 on: May 18, 2020, 04:36:50 PM »
Haha it's no problem! Similar things have happened to me. It's all a part of learning the instrument in depth.