Reaktor - Modulo on audio

gentleclockdivider

I was comparing the modulo on audio audio signals between pure data and reaktor primary .

Input signal : reaktor as sound source using stereo outputs going into reaktor as effect , left channel and right channel t going into modulo's input , same for Pure data .

Result : output of modulo recorded

There is a major difference , it seems that reaktor modulo input is automaticall rectifying negative signals , which is pretty weird considering audio signals are mostly bipolar .

Here is an audio input file , the left channel goes ( bipolar sin ) goes into left input modulo , the right channel(unipolar neg.rectifoied sine ) goes in second input of modulo .

The reakto result is negative unipolar ony , while pure data's is bipolar .

BUt it gets interesting once the left channel is negative unipolar , and the right channel bipolar

INput sgnal

So ....let's go the core route , which has no modulo at all and I am stuck building one .

gentleclockdivider

SO a modulo in core is this , works fine for events and integers but not for audio .

The division is integer (floor ) and outputs a zero , so nothng is multiplied and input is same as output

When division is float , then output is silence ( logically becasue ot the algo )

Any help appreciated

colB

https://community.native-instruments.com/discussion/comment/148231#Comment_148231

The trick is to use a float divide, then stick the 'floor' process after that. Floor is pretty straight forward, just an f2i for rounding to integer, then check if the f2i has rounded up, subtract 1 if it has.

gentleclockdivider

Thanks ,indeed a verry simple solution

Left signal is sine -2 octaves, right signal sine

Results still differ

KoaN

If it's of any help Trial'N'Error has a little core pack from primary modules...Modulo,Quantize etc.

https://www.native-instruments.com/en/reaktor-community/reaktor-user-library/entry/show/10019/

gentleclockdivider

INteresting , the trial N error module sounds the same like the primary .

It comes down to the implementation of the rounding

Where I just used float to integer , trial error used a round robin method .

But still sounds different from the pure data one ,

Iput signal , sine -1 octave panned left , sine panned right into Mod. summed outuput

colB

https://community.native-instruments.com/discussion/comment/148320#Comment_148320

Where I just used float to integer , trial error used a round robin method .

What they are calling 'round down' is a 'floor' operation. Exactly what I explained in my last post.

Using a plain float to integer isn't correct here.

gentleclockdivider

I see

Must have missed this part

quote

then check if the f2i has rounded up, subtract 1 if it has.

unquote

colB

Out of interest, is there some particular use case for modulo as an audio processor that I'm missing out on?

It 'looks' like some mutant wavefolder, and I suppose it's harmonics will be related to both inputs... but other than that?