Toslink fiber optic cables can be bought for as little as $2.99 for a 3 foot cable. It is the common kind available at both consumer and professional retail stores, catalogs, and online.
The AudioRail ADAT rx32tx32 product transfers digital audio using the Alesis ADAT Lightpipe optical protocol. The ADAT Lightpipe had its origins in the early Alesis ADAT ("Alesis Digital Audio Tape") 8-track digital recorders, and over the last decade has become a de facto standard used to connect many kinds and many brands of digital audio gear, including digital mixers, digital recorders, analog converters, pro-grade PC sound cards, signal processing devices, and other equipment. The advantage of the ADAT optical format is that it transfers 8 channels of 44.1K/48K (up to 24-bit) audio (or 4 channels of 88.2K/96K, up to 24-bit audio) over each optical cable. (Optical S/PDIF, more common in consumer audio applications, transfers only 2 channels of audio per cable.)
Unlike the more expensive glass fiber that is more commonly used in datacomm and telecomm applications, the plastic optical fiber (POF) that Toslink connections use can only be run for short distances. Short cables of around 15 feet or less can be certain to work regardless of the quality of cable and equipment at each end. Longer connections depend on the quality of cable and equipment. AudioRail uses the highest grade Toshiba Toslink transmitters and receivers, designed for up to 15 Mb/s NRZ data rates, to maximize margins on the AudioRail end. The quality of mating professional audio products and the quality of plastic optical fiber cables on the market vary from product to product, which altogether determines maximum deployable length of the plastic fiber connections.
The AudioRail ADAT rx32tx32 only communicates using the Alesis ADAT Lightpipe optical protocol, and is not compatible with the optical S/PDIF protocol.