Optionalfadeseconds of fade at a cut; 0.5 when omitted
Optionalhalfhalve the sample rate, for ambience that carries no high frequencies
Optionalmaxcut the track to this many seconds, fading the cut so it does not click
Optionalmonofold both channels into one, stored twice-referenced so a stereo consumer still works
what a track may cost: every field optional, an omitted one leaves that dimension alone