Ward-Beck AMS4 4-Channel Audio Monitoring System

The AMS4 is a versatile audio monitoring system. This one RU high unit can be used to monitor analog audio, AES digital audio and SDI embedded audio. The SDI demuxer may be added as an option.

The AMS4 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 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, AES digital and SDI modes while the SOURCE switch selects the input from that group. Use A1 through A4 for analog, D1 through D4 for AES and SD1 through SD8 for embedded signals. On power down, the last selection is stored in memory.

If a signal is lost or corrupted in the AES digital and SDI modes, the display will alternate between the source selection and the letters NL, signifying no lock. In the SDI mode, a flashing number in the source ID code signifies that embedded audio is not present. The AMS4 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 also provided. The speaker feeds are normalled through this jack to automatically mute the speakers when a headset is plugged in. Connections to the AMS4 are made on convenient pluggable screw terminals for the balanced analog and digital AES inputs and outputs. The unbalanced digital audio inputs and SDI 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 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.

• Monitors analog and AES signals
• 8 x1 Input Switcher, 4 x Analog Stereo + 4 x AES sources
• LED level meter
• Phase indicator
• Dot Matrix readout identifies selected source
• 5 Speaker full range monitor
• Line level analog output of selected source
• Front panel normalled headset jack (speakers mute when headset plugged in)
• External mute function
• 75 and 110 Ohm AES inputs
• Connections on pluggable screw terminals (analog and balanced AES) and BNC for unbalanced AES