ADATcompatible

ADATcompatible refers to devices or configurations that can transmit or receive digital audio using the ADAT Lightpipe protocol. ADAT Lightpipe is an optical multi-channel audio interface originally developed by Alesis in 1992. It uses a single Toslink optical cable to carry multiple channels of digital audio and is commonly found on professional audio interfaces, digital mixers, and multitrack recorders.

In its standard form, ADAT Lightpipe conveys eight channels of 24-bit audio at 44.1 or 48 kHz. At higher sample rates, the available channel count decreases: four channels at 88.2/96 kHz and two channels at 176.4/192 kHz. Some devices support SMUX (a packing method) to optimize channel usage at certain rates, but the basic rule is that more channels are available at lower sample rates.

ADAT-compatible equipment can function as a source, a destination, or both, provided the devices share an ADAT interface and are configured for the same sample rate and channel count. The physical connection is typically via a Toslink optical cable, though some setups use fiber optic variants. Important caveats include that ADAT is a distinct protocol from S/PDIF; while devices may offer both ADAT and S/PDIF ports, you cannot directly intermix the two formats without appropriate conversion.

Historical and current relevance: ADAT Lightpipe was widely adopted in the 1990s and 2000s as a scalable, inexpensive way to expand digital I/O. While newer interfaces (USB, Thunderbolt, Dante) have become more prevalent, many audio interfaces and digital mixers still offer ADAT I/O for inexpensive channel expansion, standby compatibility, or legacy integration.