Matrix: Can I connect an MVX-A16 card port output directly to an IFB earpiece?

An external four-wire audio device can be directly connected to an MVX-A16 port connector through the four audio pins. If there is excessive noise on the lines between the device and the matrix the device may be isolated with external isolation transformer like the BAL-8 interface.
EHX allows the changing of the audio output level between -45 to +15dB.  With a +15dB output reference level, it is possible to drive a 200 to 400 Ohm headset directly with a port output for such uses as direct IFB feed.

Analog port card (MVX-A16)
Input Format----------Balanced
Output Format--------Balanced
Ground Isolation-----None; expected at User Panel/Station
Analog port card outputs
Level--------------------------0 dBu nominal
Impedance-----------------100 Ohms balanced
Frequency Response---30 Hz–22 kHz ± 3 dB
Distortion-------------------<0.05 %, @ 0 dBu, 300 Hz to 10 kHz;
                                           <0.1 %, @ 0 dBu, 100 Hz to 20 kHz
Analog port card inputs
Level--------------------------0 dBv
nominal Impedance-----600 Ohms balanced
Frequency Response--30 Hz–22 kHz ± 3 dB
Distortion-------------------<0.05 %, @ 0 dBu, 300 Hz to 10 kHz;
                                           <0.1 %, @ 0 dBu, 100 Hz to 20 kHz