The BSS BLU-SI card is a 32 x 32 interface between Soundcraft Si Series consoles and the BLU Link digital audio bus. The card allows connection to a wide variety of Harman products equipped with a BLU Link interface such as BSS London BLU 800, dbx® PMC or Crown® PIP-BLU interfaces amongst others.

BLU Link is a low latency, fault tolerant digital audio bus of 256 channels which using standard CAT 5e cabling gives a distance of 100m between compatible BLU Link enabled devices.