Wordclock:
When using multiple devices connected through digital audio formats like S/PDIF, AES/EBU, ADAT or TDIF, it is necessary to synchronize them to a single word clock generator. Word clock is used to keep a perfectly timed and constant bit rate between all synced devices to avoid data errors. A word clock generator creates digital pulses that contain no other data (i.e. audio). These pulses clock the internal oscillators of each device and are essential to avoid frequency drift.