At the very beginning of a sound file is the "SAMP" header. This is used to determine if the disk file is indeed a SAMP sound file. It's attributes are as follows: #define ID_SAMP MakeID('S','A','M','P') In assembly, this looks like: CNOP 0,2 ;word-align SAMP dc.b 'SAMP' sizeOfChunks dc.l [sizes of all subsequent chunks summed]