User Manual

User's Guide Fireface 800 © RME

Special Characteristics of the SPDIF Output

Apart from the audio data itself, digital signals in SPDIF or AES/EBU format have a header

containing channel status information. False channel status is a common cause of malfunction.

The Fireface 800 ignores the received header and creates a totally new one for the output sig-

nal.

Note that in record or monitor modes, set emphasis bits will disappear. Recordings origi-

nally done with emphasis should always be played back with the emphasis bit set!

This can be done by selecting the Emphasis switch in the Settings dialog (SPDIF Out). This

setting is updated immediately, even during playback. The Fireface’s new output header is

optimized for largest compatibility with other digital devices:

• 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz, 192 kHz depending on the current

sample rate

• Audio use, Non-Audio

• No Copyright, Copy Permitted

• Format Consumer or Professional

• Category General, Generation not indicated

• 2-channel, No Emphasis or 50/15 µs

• Aux bits Audio Use

Professional AES/EBU equipment can be connected to the Fireface 800 thanks to the trans-

former-balanced coaxial outputs, and the ‘Professional’ format option with doubled output volt-

age. Output cables should have the same pinout as those used for input (see above), but with a

male XLR plug instead of a female one.

Note that most consumer HiFi equipment (with optical or phono SPDIF inputs) will only

accept signals in ‘Consumer’ format!

The audio bit in the header can be set to 'Non-Audio'. This is necessary when Dolby AC-3 en-

coded data is sent to external decoders (surround-sound receivers, television sets etc. with AC-

3 digital inputs), as these decoders would otherwise not recognize the data as AC-3.

16.3 MIDI

Fireface 800 offers one MIDI I/O via 5-pin DIN jacks. The MIDI ports are added to the system

by the driver. Using MIDI capable software, these ports can be accessed under the name Fire-

face Midi. Using more than one Fireface, the operating system adds a consecutive number to

the port name, like Fireface MIDI (1) etc.

The MIDI inputs can not operate multi-client, so a MIDI input signal can not be distributed to

several programs at the same time. Such a functionality can be achieved with third party tools.