Audio device in never return true 0?

Hello there !

I hope my post i in the good place, thanks for reading me :slight_smile:

My question is :

Why a “CHOP audio device in” never return en true 0 when there is no sound ?
I mean, if i put an analyze, the outpout value is near 0, but not zero, and not stable.

I’m using this value in an audio reactiv setup, and having a moving signal even if there is no sound is annoying and a big problem.

I tried whith many input, it seems that even with no input selected, there is a low signal.

So is it normal ? If not, what am i missing ?
If yes, is there any way to solve this ?
I mean, i can understand that any physical audio input always have some noise, but how am i supposed to deal with it ?

I tried to use a math range but the moving 0 signal is in the middle of the actual normal signal range (-1 to 1)

Let me know if it’s not clear enough, i’ll try to get some more details.

Thanks :slight_smile:

Yeah I think your computer’s audio devices will always be creating a little bit of noise, this isn’t something TouchDesigner is doing.

You can use a Lookup CHOP to “flatten out” the values that are VERY near zero. This would be basically an advanced version of what you were trying to do with the math CHOP range. The index range of the Lookup CHOP would be -1 to 1 instead of the default 0 to 1, and then you would input a linear lookup table to the second input maybe using a Pattern (most likely a few Patterns joined together) or S-Curve CHOP - though it would have to be an “inverted” S-Curve like we were just discussing here.

Are you using the wave-form specifically to trigger something? Usually if someone is doing something audio reactive, they use the spectrum - or the “audioAnalysis” TOX in the built-in Tools Palette - to pick a frequency which triggers a certain action. Using the wave-form directly is not the best way to trigger stuff and usually is just applied to a SOP or something to mimic the waveform in some geometry if anything.

Hello @Peeet, and thanks !!

Usually if someone is doing something audio reactive, they use the spectrum

Yeah i’m using a spectrum with the audio device, and an enveloppe to get a proper signal to trigger a CHOP trigger with the correct threshold to get à kick 0/1. But the noise is even more annoying in this setup as it make the post-enveloppe signal being near 1 and triggering the rest of the network.

But the pattern-join-lookup setup is working very nicely, I get a nice flat signal when sound is off !

or the “audioAnalysis” TOX in the built-in Tools Palette

I didnt know about this tool… and it appears that its approximatively what i was trying to do by myself, in a much more detailled and convenient way :sweat_smile:

Now I have two pathes in my audio reactive network to play with, depending on what i want to animate !

Thank’s again, TD is such a huuuge universe to play in, nice to have some kind people to help beginners