M-Audio manual ProFire 2626 Operation at High Sample Rates, About S/MUX II and S/MUX IV modes

ProFire 2626 User Guide 11

ProFire 2626 Operation at High Sample Rates

ProFire 2626 can operate at high sample rates including 88.2/96 kHz and 176.4/192 kHz. However, the number of available inputs and outputs is reduced when operating at these rates and certain input and output ports are disabled as a result (see the “About S/MUX II and S/MUX IV modes” section for additional information). Furthermore, at high sample rates, the number of software returns is automatically reduced to match the number of available hardware outputs and to preserve system resources. This section describes how channels are affected at high sample rates.

Note that since Windows and OS X operating systems handle audio differently, each operating system is described separately.

About S/MUX II and S/MUX IV modes:

An ADAT port is designed to transfer eight channels of audio at sample rates up to 48 kHz. When operating at higher sample rates, the port must operate in S/MUX II (up to 96 kHz) or S/MUX IV (up to 192 kHz) mode. S/MUX II mode combines pairs of ADAT channels (i.e. channels 1/2→1, 3/4→2, 5/6→3, 7/8→4) to create four high bandwidth channels capable of transferring high resolution audio up to 96 kHz. S/MUX IV mode combines groups of four ADAT channels (i.e., 1-4→1, 5-8→2) to create two high bandwidth channels capable of transferring high resolution audio up to 192 kHz.

Sample Rate	Number of Channels
	(per ADAT port)
44.1-48 kHz	8
88.2-96 kHz	4	(S/MUX II)
176.4-192 kHz	2	(S/MUX IV)