If you're doing multitrack recording (bwf wtc) defrag will reduce the performance of playback as the data will write to the disk sequentiall (all files interleaved as the data comes in) but defragging will separate all the data so that the seeking is increased dramatically. Even for 'electronic' style projects, defragging your audio partition shouldn't be necessary, same with a sample library partition (as the samplelibs will tend to write contiguously during install.)

Overall though I try to keep a 'working' partition for audio and then move data off of that as projects are finished (to backups or backup partitions etc) for longterm storage & recall. This alone will keep your audio drive from being 'fragmented', and larger studios probably just format the working partition (or hot swap in a new drive) before starting a new project.

John
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"The only Band is a Real Band"
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