Bitcrushing

I was wondering if there’s an effect or a prompt that could lower the bitrate in an audio file. If there isn’t a plugin for bitcrushing is there a nyquist prompt that could lower the bitrate of the audio file?

See this topic: https://forum.audacityteam.org/t/bit-crusher/62001/1

Instructions for installing Nyquist plug-ins on Windows: https://manual.audacityteam.org/man/installing_effect_generator_and_analyzer_plug_ins_on_windows.html#nyquist_install

You can search for a VST plug-in.

…I’m not 100% sure what a “bitcrusher” does. I sort-of thought it just zeros-out the low-order bits and that requires some kind of “special processing”.

If you simply want to reduce the bit depth, that’s fairly easy to do. When you reduce the volume (in integer format) you loose bit-resolution. Each bit represents 6dB, so if you reduce the volume by 6dB (Amplify by -6dB) you are only using 15-bits. At -48dB you are down to 8-bits and at -60dB you are down to 6-bits, etc.

So if you wanted 6-bits:
- Amplify by -60dB.* (You’ll have to do that in two steps because Amplify only goes down by -50dB at a time.) That’s VERY quiet but since Audacity works internally in floating-point you haven’t lost any bits yet…

- Export as 16-bit WAV. (Now you’re down to 6-bits and a very-quiet file).

- Open the -60dB file and re-Amplify to bring the volume back-up. (Again, you’ll have to do this twice if you are below -50dB).

…Alternatively, you could have reduced by 12dB and exported as 8-bits to end-up with 6-bits of resolution.



\

  • I’m assuming you’re starting with a 0dB Normalized file that’s using all 16-bits.

bit-rate & bit-depth are two different things.
Bitcrushing reduces bit-depth.