[astrange]

You always want dithering no matter the bit depth, but 16-bit is actually quite a lot - there's literally no point in better than CD-quality audio. (Except of course that real life is in surround not stereo.)

But yes, if you're doing it repeatedly you'd want an un-dithering filter. Noise reduction tends to do this by accident but it helps if you know what the dither shape was.