A few questions for webmasters that know about AUDIO encoding
 

I have ac3 source files that need to be output as either mp3 or wav.

What's the difference between destination format:

MP3 16bit int
MP3 24bit int
MP3 32bit int
MP3 32bit float

My software defaults to 32 bit float, which is what I usually use.

Also, using 2-pass mode, what's the difference between dumb, hybrid and float?

Also, though I know the difference between CBR and VBR, wtf is Alt ABR?

I usually resample to 44.1kHz and use MP3 32bit float, VBR avg. 192Kbps, 2ch joint stereo if that helps...

meh...i guess i know less than i thought about audio....