MOD AMT set to OSC1 or 2 wave

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1

Trying to work out why the sound cuts out when I set the MOD AMT to OSC1 wave

it modulates the wave as I expected but it also cuts out the sound too.

anyone know why it works this way, if I just use the OSC1 wave control manually it doesn’t cut out the sound

maybe theres a reason why this happens

thanks

2

Funny, I was playing yesterday with that and found out that it is like how you say it.
I do not know if it is a bug. Funny is when you turn the LFO to very slow, (triangle) I have even the feel the pitch is changing a bit.
When you change the Rate from the LFO you hear it very clear that the pitch is changing. ( like you hear 2 osc´s)
A bug??? I like this bug.
You can control this in any way with the AMT..
Nice to get some brainwaves.

Wish you something..
Regards Luloop

3

I haven’t played with this yet on the actual machine, but are we trying to generate a pulse width greater than 100% or less than 0% ? :slight_smile:

On analog oscillators sometimes the rectangular waveform becomes shut off when the mod value for the PWM circuit becomes too small or too high.

Maybe that is happening here? The final waveshape value is the sum of the waveshape control plus the amount of modulation applied to the waveshape. The wide range of the modulation then takes the waveshape from triangle through rectangle to a narrow pulse to nothing and beyond?

4

Hi there!

A pulse with 0% means that there is no pulse. 100% means the same, but inverted - it’s only a constant voltage. So in both cases you’ll hear no sound.
Since the oscillators in the Sub are analog cicuits, you can “overmodulate” the pulse width like Mikeh wrote. This is absolutely normal and every modular user can confirm (while in digital circuits you can limit the “unwanted” modulation by software).

I think this is a psychoacoustic phenomenon. Our ears misintepret a changing waveform as a different frequency. This is especially good to hear with different pulse widths. I think it’s because of the different energy of different waveforms. The frequency however is determined by the periodic length (duration) of a single wave which will not change with different waveforms.

cheers,
Bernard

5

Thanks for the info

I didn’t think it was a bug but really didn’t understand it until now so thanks for that.

:smiling_face:

6

Will try this out tomorrow sounds cool :smiling_face:

7

I got a chance to play with it - here’s how I demo it:

Do an “Init Preset”

Set Mod1:

  • Rate 3
  • Square Wave
  • Mod Dest → Osc1 Wave
  • Mod Amt 0

Set Osc 1:

  • Square Wave
  • Amp 5-6

Play:

  • roll ModWheel all the way up

  • slowly turn Mod1 Mod Amt from 0 to +3

  • Osc1 wave alternates from square to pulse

  • the pulse gets narrower as the mod-amt is increased

  • mine drops out altogether around 2.8

  • can’t make a pulse thinner than zero

  • now set Mod1 Hi-Range

  • set rate to around 12 and zero beat with Osc1

  • get nice chunky blats

  • mmmm.

8

Hi,
The psychoacoustic phenomenon, Bernhard call it like this, is more effective when Mod 1 is set to triangle.
I also activate Osc 2 with nearly the same setting as Osc 1 .
playing around with Beat freq, Mod Amt and the Mods makes big fun.

Regards Luloop.