I can’t really figure out from all the videos I’ve watched concerning the question of “do I dither before or after converting to 16 bits”?
I’ve always dithered my 24 or32 bit files first and then converted to 16 and am wondering if I’m doing this backwards or if it matters.
what is your original bit depth?
Dithering needs to be done once: At the mastering stage.
And that only goes for music.
Fredo
I understand that part. The question is the order of events:
master the 64 bit file,
convert to 16 bits
and then dither?
master the file
dither it
convert to 16 bits?
The order does not matter.
Dithering should be applied to the original file, then converted. If you convert to 16 bit depth without dithering, all audio below -96dbFS is lost which prevents dithering from doing its thing.
i would export the 64bit project to 64bit, to have it clean.
that way you don´t need to apply the dither 2 times if you want 2 different bit depth in the future.
Thank you. That’s the answer I was looking for and, luckily, the way I’ve been doing it.
just to stay away of 2 times dithering 
Dithering should be part of the conversion process.
A good read is this one:
If you do two steps of bit reduction, you need to dither twice.
yes, but is better to avoid it. for that, its better to export from your project at same project bit depth , this way, from that you can go at any another lower bit depth directly without dithering twice. This was my advice.