This tool is use to is used to netlists into wav audio files. The details below come straight from the MAME documentation. To be honest, 99.9% of MAME users will never need to use this program, but here's some details anyway.
-i, --input=Value input file
-o, --output=Value output file
-a, --amp=Value amplification after mean correction
-r, --rate=Value sample rate of output file
-v, --verbose be verbose - this produces lots of output
-q, --quiet be quiet - no warnings
--version display version and exit
-h, --help display help and exit
> nlwav [options]