Effects in real time

Hi everyone:

Is it possible to control volume, speed and effects in real time, when a file is played with audacity?
I’m designing human interfaces with Arduino for deaf childs and old people with problems on the hands.
I can identify movements and fingers positions, and then send a value, but I can not see how I can modify those parameters (speed, volume, etc in Audacity in real time
I could use a keys combination too.

Could you help me, please?

Thanks for your patience.


I think it’s still true that Audacity doesn’t do anything in real time past stop, start and some timer jobs.


Volume: Yes.
For the overall volume, use Mixer Toolbar: http://manual.audacityteam.org/man/mixer_toolbar.html or the computer sound system control, or the volume control on your amp / speakers.
For “per track” volume control, use the track Gain slider: http://manual.audacityteam.org/man/audio_tracks.html#gain

Speed: Yes, but with the limitation that playback needs to stop to change the speed setting
Use the “Transcription toolbar” speed control: http://manual.audacityteam.org/man/transcription_toolbar.html
Note that this affects both tempo and pitch - it literally changes the playback speed.

Effects: No,
Though some effects have “real-time preview”: http://manual.audacityteam.org/man/real_time_preview_of_effects.html

If you are using Windows for running the audio playback, you may be better to use a lightweight VST host rather than Audacity, and control effects through MIDI Control messages.