When you specify a different sample rate for a bounced file (for example, when mixing a session recorded at 96 kHz to 44.1 kHz for release on an audio CD), Pro Tools uses the Conversion Quality option to determine the quality of sample rate conversion used.There are five possible settings, ranging from Low (lowest quality) to Tweak Head (highest quality). The higher the quality of sample rate conversion, the longer it takes to convert the bounced file.