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Difference between LFO Noise and Random? - Printable Version

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Difference between LFO Noise and Random? - mgd - 07-24-2021

Hi!

I've been playing with the 8 LFOs on one of my CV16 and from what I can see they easily replace "normal" LFOs for my average modulation purpose - well done. Together with the 8 envelopes that alone seems worth another CV16 and possibly even another NerdSEQ...will have to save some cash for that Big Grin

Anyway, here's a question regarding the LFO waveforms Noise and Random:
What exactly is the difference between the two?
From my experiments I deduce they both provide some form of S&H with Noise being much more erratic and Random delivering smaller jumps.

Could someone (Thomas?) provide more details as to what it actually is?

Somehwere else in the manual it says "white and pink noise". Is the S&H from Noise based on white noise while Random is based on pink noise?
Or something else?

Kind regards,
Michael


RE: Difference between LFO Noise and Random? - XORadmin - 07-24-2021

The noise is actually just a white noise.
Random is not a noise signal at all, but is derived from the other waveforms.
Waveforms are splitted into 4 pieces while randomly the piece and randomly the waveform is selected. So you get a weird combination of parts of the waveforms. Check them in the scope and you can see all the parts. Looks quite fun :-)


RE: Difference between LFO Noise and Random? - mgd - 07-24-2021

I've just looked at them on the Mordax Data and the attached image shows what it looks like.

Blue is Noise and red is Random (or that's my understanding of the images; Random being the last possible selection and Noise the one directly before it).

Scale for both on the Data is 0.5V; they are shifted a bit vertically. On the NerdSEQ they have the same Applification and Offset, Speed is 20 and 30 for Noise and Random. All other settings are identical. They both are from the outputs of one of my CV16 from the Automator Screen.

To me that looks like a Sample & Hold function albeit there is some small noise superimposed on the flat parts.

Update: Now with the image attached...


RE: Difference between LFO Noise and Random? - XORadmin - 07-24-2021

(07-24-2021, 02:00 PM)mgd Wrote: I've just looked at them on the Mordax Data and the attached image shows what it looks like.

Blue is Noise and red is Random (or that's my understanding of the images; Random being the last possible selection and Noise the one directly before it).

Scale for both on the Data is 0.5V; they are shifted a bit vertically. On the NerdSEQ they have the same Applification and Offset, Speed is 20 and 30 for Noise and Random. All other settings are identical. They both are from the outputs of one of my CV16 from the Automator Screen.

To me that looks like a Sample & Hold function albeit there is some small noise superimposed on the flat parts.

Update: Now with the image attached...

What do you mean outputs of the automator screen? The CV16 LFO are own LFO functions and not related to the automators.
I'm pretty sure the CV16 Random LFO should look different and you should be able to recognize the (part-) waveforms.


RE: Difference between LFO Noise and Random? - mgd - 07-24-2021

Ah, I see...there were some misunderstandings on my part.

I had used the global LFO from the Automator Screen and routed that through the CV16. That's what you see on the image. I now have found the LFO from the CV16 and set them up and there I do indeed see the curve segments that you mention. LFO waveform Noise still gets me some form of Sample & Hold and that's essentially what I want anyway Smile

I also see that the parameter ranges for the local LFOs of the CV16 and the LFO from the Automator Screen are different. Not a biggy but I have to keep that in mind.

Back to the image as of above:
The blue line is the NerdSEQ (Automator Screen) LFO waveform Noise and the red line is the NerdSEQ (Automator Screen) LFO waveform Random. Both routed through a CV16. They look quite different from what I get from the local/native CV16 LFOs.


RE: Difference between LFO Noise and Random? - XORadmin - 07-24-2021

(07-24-2021, 03:01 PM)mgd Wrote: Ah, I see...there were some misunderstandings on my part.

I had used the global LFO from the Automator Screen and routed that through the CV16. That's what you see on the image. I now have found the LFO from the CV16 and set them up and there I do indeed see the curve segments that you mention. LFO waveform Noise still gets me some form of Sample & Hold and that's essentially what I want anyway Smile

I also see that the parameter ranges for the local LFOs of the CV16 and the LFO from the Automator Screen are different. Not a biggy but I have to keep that in mind.

Back to the image as of above:
The blue line is the NerdSEQ (Automator Screen) LFO waveform Noise and the red line is the NerdSEQ (Automator Screen) LFO waveform Random. Both routed through a CV16. They look quite different from what I get from the local/native CV16 LFOs.

The automator LFO is one white noise and the other one pink noise. There is no random noise with the automators.
The CV16 LFO got white noise or the random one.
They are indeed different because the handling is completely different (and also up to 16 got to be possible to run at the same time)