AMS4-1AA

The AMS4-1AA is a versatile audio monitoring system. This 1RU high unit can be used to monitor analog audio and AES digital audio. The AMS4-1AA features an 8 x 1 input switcher (four analog sources, four AES sources) with auto recognition of 75 or 110 Ohm AES signals. A direct balanced stereo analog audio output of the switcher is available on the rear panel. A ten segment LED stereo VU meter and phase indicator is included on the front panel.

The AMS4-1AA offers full-range acoustic monitoring, and may be muted via external control. Two front panel push button switches, MODE and SOURCE, and a dot matrix LED readout allows the user to select the source to be monitored. The MODE switch steps through analog and AES digital modes while the SOURCE switch selects the input from that group. Use A1 through A4 for analog and D1 through D4 for AES. On power down, the last selection is stored in memory. If a signal is lost or corrupted in the AES digital mode, the display will alternate between the source selection and the letters NL, signifying no lock. The AMS4-1AA will automatically detect whether the AES/EBU digital signal is balanced (110 Ohms) or unbalanced (75 Ohms). In the event that both a balanced and unbalanced signal is connected simultaneously to the same AES input, random selection between the two sources will occur. A convenient front panel mounted TRS headset jack is provided. The speaker feeds are normalled through this jack to automatically mute the speakers when a headset is plugged in.

Connections to the AMS4-1AA are made on convenient pluggable screw terminals for the balanced analog and digital AES inputs and outputs. The unbalanced digital audio inputs are made on 75 Ohm BNC connectors. The EXT MUTE IN requires a closure to ground to mute the monitor. Once muted, the display window of the AMS4-1AA will alternate between the selected source ID and the word MUTE. The open collector output EXT MUTE TALLY pin will be activated. Connections to the external mute control and tally are available on a pluggable screw terminal, located on the rear panel.