Brackish said:
But some give the advice to "track at 16 and do post
work in 24", then dither back.
The internal bit depth your DAW uses is probably (much) higher than 16 bits. Most modern software works at 32- or even 64-bits.
Here's an expriment: Set up a bus chain, with bus 1 feeding bus 2, which then feeds bus 3, and so on up to 5 or 6. Set each bus to reduce the signal level by, say, 20dB. Now on the last bus, add a limiter or 2, as many as you need to raise the level back up by the amount the bus chain lowered it.
Feed a 16-bit track into the signal chain. Even though your bus chain reduces the overall level by 100dB or more, the final ouput, when the signal is brought back up, will sound the same.
What does this illustrate?
The absolute theoretical dynamic range limit using 16-bits is
96dB. You used your DAW to reduce the signal beyond this limit. If your DAW worked at 16 bits internally, when you raised the signal back up again, there'd be nothing there. Once you go beyond 96dB, you're out of bits.
Try it with 24-bit files even. Reduce the total level by 150dB .. The sound will still be there when you re-raise the level.
So up-converting to 24 bits for post work is redundant, since your software is already working at 32- or 64-bits