NMX-ATC-N4321-C Audio Transceiver Card

Audio over IP Transceiver Card

The NMX-ATC-N4321 Audio Transceiver is an audio-over-IP solution that both sends and receives two-channel balanced or unbalanced audio over IP. Simply connect a balanced audio input into the IN port and it's converted to IP packets that are switchable and routable just like data or voice. The balanced audio output receives an audio-over-IP stream and decodes to analog while preserving audio fidelity. Perfect for point-to-point or point-to-multi-point audio delivery, the NMX-ATC-N4321 provides audio matrix switching and distribution using the same control options as SVSI's Networked AV video switching and distribution solution.

With two auto-sensing gigabit Ethernet ports, units can be stacked to deliver low-latency multi-channel audio over a house network or a physically separate network. One Ethernet port is POE for use with a POE switch, eliminating the need for an external power supply. An audio matrix with any number of inputs and outputs can be constructed with the NMX-ATC-N4321. Since control is the same as for SVSI's video over IP matrix, video and audio matrices can be combined and routed using the same controller for the ultimate in digital media distribution.





  Version Language Size Uploaded
    1.05 MB Oct 22, 2020
    250 KB Oct 22, 2020
updated: Jul 24, 2020
    9.8 KB Jul 24, 2020
version 2020-07-28, updated: Jan 04, 2021
2020-07-28     102 MB Jan 04, 2021
SVSI N4000 Audio over IP Transceiver Firmware Updater
version 1.0.4, updated: Nov 24, 2020
1.0.4     61.4 MB Nov 24, 2020
Data Sheets
    489 KB Oct 23, 2020
Install Guides
    607 KB Mar 29, 2018
Quick Start Guides
    638 KB Oct 22, 2020
Product Guides
    88.8 KB Oct 23, 2020
    83.6 KB Nov 10, 2020

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  • Input: 2-channel user selectable balanced or unbalanced audio.
  • Output
    • 2-channel balanced audio (1x 5-pin phoenix connector)
    • 2-channel unbalanced audio (headphone jack)
  • Analog-To-Digital Conversion: 16-bit 32 kHz, 44.1 kHz and 48 kHz
  • Phantom Power: 48V on each of the input audio pins (L+, L-, R+, R-), 7mA per pin, or 14mA per channel
Latency Audio: 20ms (excluding network propagation)
Communications Ethernet: Multi-cast, unicast, IGMP v3, IPv6, layer-2 and layer-3 switch compatible.
  • +12V 2A: One 12 Volt DC power input
  • P0 POE
    • 8-wire RJ45 female
    • 10/100/1000 Mbps 10/100/1000Base-T auto-sensing gigabit Ethernet switch port. Provides both the network connection and the power to the Encoders and Decoders
  • P1
    • 8-wire RJ45 female
    • 10/100/1000 Mbps 10/100/1000Base-T auto-sensing gigabit Ethernet switch port
  • GPI: General purpose input
  • RELAY: 2-channel relay port
  • AUDIO IN: 5-pin terminal Phoenix connector which provides user-selectable balanced/ unbalanced input. Dedicated audio input.
  • AUDIO OUT: 5-pin terminal Phoenix connector which provides user-selectable balanced audio output. Dedicated audio output.
  • HEADPHONE JACK: 2-channel, unbalanced audio output
Controls and Indicators - Front Panel
  • RESET button: Recessed pushbutton. Press to initiate a 'warm restart' causing the processor to reset, but not lose power. A reset does NOT affect the current settings.
  • ID button: Recessed pushbutton. Press to send a notification out on the network to identify the unit (the notification causes a pop-up dialog in N-Able and N-Command).
  • POWER LED: On solid (green) when operating power is supplied (via PoE or local power supply). This activity is also shown by the PWR LED on the rear panel.
  • STATUS LED: On flashing (green) when there is software activity. This activity is also shown by the STAT LED on the rear panel.
Controls and Indicators - Rear Panel
  • PWR LED: Same as POWER LED described above.
  • DVI LED: On (green) when a DVI input connection exists
  • STAT LED: Same as STATUS LED described above.
  • STRM LED: On (green) when the unit is streaming video
  • Regulatory Compliance: FCC, CE, and NTRL
  • Recommended Accessories: NMX-ACC-N9206 (FGN9206), 2RU Rack Mount Cage with Power for Six SVSI N-Series Card Units
FG Numbers FGN4321-CD
  • NMX-ACC-N9206

    2RU Rack Mount Cage with Power for Six SVSI N-Series Card Units