I’m about to join different songs (in 192/24) together in one file. Thing is I don’t want any dither or quality loss, I’m not doing ANY changes, just joining them. When I import them then it says 32 float
. Will that add any processing ? or should I change it to 24bits (set sample format) ?
Let’s see if I remember this. Yes, set Audacity Project to the exact standard you wish to use. Then turn dithering off in:
Audacity > Edit > Preferences > Quality.
Audacity will still try to convert to 32-floating internally, but the conversion error both directions should be zero, particularly if you do no effects. I think that’s one way to get bit-accurate transfers (someone will correct me).
Note this does not work with any compressed format like MP3.
Dithering will not occur (even if enabled at “High-quality conversion” in Quality Preferences) when pasting, even if the Default Sample Format in Quality Preferences is 16-bit or 24-bit.
Dithering will occur (unless disabled) when processing audio, unless Default Sample Format is 32-bit float. This is because Audacity has to return the audio to the track after processing it in 32-bit float. Processing means using an effect.
So to be sure there is no dithering in the project when dithering is enabled, you must use 32-bit float resolution, not the same resolution that the file happens to be.
Dithering is still preferred when exporting from a 32-bit float project to a lower resolution audio format.
PS You cannot actually import 24-bit files in 24-bit resolution - even if your quality preferences are 24-bit, the 24-bit file will import at 32-bit. That’s what the code says:
if (mFormat != floatSample &&
mFormat = floatSample;
but I’m not sure why that decision was made rather than “don’t import at a lower resolution than the file has”.