I wouldn't worry, 32 bit is completely inappropriate unless it's part of a signal being being digitally processed within a DSP function where arithmetic precision errors are to be reduced whilst processing the samples. As a sample dynamic range 32bit exceeds the range of electrical nervous system noise in your ear drum and brain ( that hiss you hear in extremely quiet places) whilst standing next to the exit thrust of a jet engine. (which would destroy your hearing in an instant).
Real measures:
Perfect human hearing is generally considered to be able to detect 140dB of range in extreme circumstances.
24bit audio can theoretically provide 144dB of dynamic range but is usually slightly less through digital noise.
In the early 1980s through subjective assessment i think i am right in saying Ampex determined that 108dB range in a dithered digital signal was the point at which no noise could be heard by a person listening to a quiet passage of audio.. Ie the dither noise was below the perceived listenable dynamic range of a quiet musical passage.
Simon
