Word Clock
Overview
The term "Word Clock" is used to describe a one cycle per sample period "square wave" signal used for synchronization of digital audio equipment. The signal is typically "TTL level" 5 volt p-p and is carried on 75 Ohm coaxial cable with BNC connectors.
History
Earlier digital audio systems employed a number of formats of interconnection, many of which were proprietary. Some were parallel; in which case each "bit" was carried on a separate conductor and a Word Clock signal was used to synchronize the timing of the transmission of each complete "word" of 16 bits, once per sample period.
In other systems; the left and right channel's digital audio data was transmitted in a serial manner, in parallel with a Word Clock signal which was used to synchronize the receiver with the beginning of the transmission of each serial "word."