How to dynamically mod volume of one track to match another?

[Raiten]

Hello,

I am trying to dynamically modulate the volume of one track to match the volume of another. So when the reference track is loud, the volume of the second track will be loud. When the reference track is low, the volume of the second track will be low. In areas of silence on the reference track, the second track will be silent.

Is there a plug-in for doing something like this?

Thank you,
Matt

[Trebor]

http://en.wikipedia.org/wiki/Envelope_detector#Audio

Apply this full wave rectifier plugin applied to the control track ... http://www.shellworld.net/~davidsky/rectimod.zip

Then apply a low pass filter to the rectified track to smooth out the ripples.

Those two processes will create the envelope track.

[Raiten]

Fabulous! Thank you very much.

Matt

[Trebor]

You'll still have to multiply your audio with the envelope track using something like this Nyquist code ...

Code: Select all

    (sim (mult (aref s 1) -0.5)
       (mult (sum 0.5 (scale 0.5 (aref s 0)))(aref s 1)))

http://forum.audacityteam.org/viewtopic ... 121#p37075

(I think )

[steve]

http://en.wikipedia.org/wiki/Envelope_detector#Audio

Apply this full wave rectifier plugin applied to the control track ... http://www.shellworld.net/~davidsky/rectimod.zip

Then apply a low pass filter to the rectified track to smooth out the ripples.

Those two processes will create the envelope track.

Probably better to use "follow"
http://www.audacity-forum.de/download/e ... l#index189

[Trebor]

My method does work ...

440Hz sine wave amplitude modulated with pop tune (mp3 in zip).zip

(231.81 KiB) Downloaded 254 times

"Follow" is a more elegant solution though, (I wasn't aware of its existence).

[BTW I bet no-one can correctly "name that tune" ].

[Raiten]

Thanks for both the solutions.

Matt

[Raiten]

So I finally got the tracks recorded that I wanted to use this function with and I can't figure out how to use this command. So I figure I highlight two tracks, select Nyquist Prompt, then I am not sure about what to enter for the variables.

Any suggestions for this application?

Thanks,
Matt

[steve]

Trebor's code works on one stereo track with the "control" track as one channel and the "tune" (to be modulated) as the other channel.

The exact steps to do this depend on which version of Audacity you are using (it's easier if you are using Audacity 1.3.12 than with 1.2.6, so if you're still on the (very) old 1.2.6, this could be a good opportunity to upgrade.)

Also, do you have your tracks as mono or stereo files? Have you exported them as WAV files? Do you need your final result to be in stereo, or is mono OK?

[Raiten]

Hi Steve,

I am using 1.3.12, had a few crashes with this project so far but I am saving after every command so its okay.

I wanted to use your suggestion to use the "follow" command and it was my understanding that this is a function of the Nyquist Prompt.

The "tune" track is a stereo .wav file and the "control" track is a stereo .wav file. My goal is to produce the final resulting track in stereo. What I am creating will not work if the stereo aspect of the "tune" track is not preserved.

Thank you for your help.

Matt