In contrast with what many people believe the data throughput bottleneck with audio is almost never the network infrastructure. Even one 1GbE connection can accommodate over 500 tracks of 24 bit, 48 KHz uncompressed audio. Because of the huge number of tracks which comes into play when several DAW's are used the seek time of the drives eventually becomes the limiting factor.
Audio applications are not as data hungry as video or film clients and the best advice one can give is that it is better to select a DDP with lower capacity drives (500 GB for example) and more of these then less drives with higher capacity. Thus reducing the seek time of the drives and allowing more streams of audio to be utilized simultaneously.