Apple Final Cut Pro 6 - Manual (Page 195)

194 Part III Setting Up Your Editing System
Digital Audio Connectors and Signal Formats
Although digital audio signals are completely different from analog signals, the same
connectors are often used for convenience. For example, an XLR connector can be used
to carry an analog audio signal or an AES/EBU digital audio signal.
AES/EBU
The AES/EBU digital audio specification was jointly developed by the Audio
Engineering Society (AES) and the European Broadcasting Union (EBU). AES/EBU audio
signals typically use XLR connectors, but 25- or 50-pin D-subminiature connectors can
also be used for multiple channels on interfaces or mixers.
Traditionally, AES/EBU sample rates were limited to 44.1 and 48 kHz at up to 24 bits per
sample. However, a “dual wire” mode allows some equipment to pair AES/EBU
connectors to increase the sample rate. Some newer devices also support “single wire”
mode with sample rates up to 192 kHz.
S/PDIF
Sony/Philips Digital Interface Format (S/PDIF) is a consumer-level variation of the AES/
EBU digital audio protocol. S/PDIF audio data can be transmitted several ways, including:
 Via coaxial cables with an RCA connector
 Via optical TOSLINK
Connectors for S/PDIF signals are found on most consumer digital equipment, such as
DAT recorders, CD players, DVD players, MiniDisc equipment, and some audio interfaces.
Dolby Digital (AC-3)
Dolby Digital (AC-3) is a compressed digital audio signal format used for transmission
of 5.1-channel surround sound. Mono and stereo signals can also be carried in this
format. Typically, this audio signal is embedded within a S/PDIF signal and carried via
TOSLINK or coaxial cables with RCA connectors.
DTS
Digital Theater System (DTS) is a compressed digital audio signal format used for
transmission of 5.1-channel surround sound. This format is primarily used in movie
theaters and on DVD releases. More recent variations of DTS support more than six
channels of audio. This audio signal is usually embedded within a S/PDIF signal and
carried via TOSLINK or coaxial cables with RCA connectors.