IP Paging

Data Sheet

User Guide

User Guide

Wideband IP Paging Adapter With Zone Control for Integrating Legacy Analog Amplifiers

The 8373 is a paging adapter for IP enabling zoned analog voice paging systems. The endpoint is a SIP interface to seamlessly bridge an analog paging system to VoIP. Common application environments include schools, hospitals, retail stores, etc.

The 8373 is a PoE IP Zone Paging Adapter for integrating legacy voice paging systems into a hosted or premise UC environment as a third party SIP endpoint. The Adapter eliminates the need for a legacy zone controller, however, the 8373 can also be deployed to add page zones to an existing single zone system. Features include G.722 wideband support with isolated and balanced line output for optimum clarity and intelligibility without hum or noise.

To the network side, the 8373 is a SIP endpoint for easy integration with an IP telephone system. It is configured using the intuitive web interface or provisioning capabilities.

On the paging side, the 8373 provides balanced audio output using both an XLR connector and terminal block for easy connection to an amplifier, along with a dry contact closure if required by the amplifier.

The high voltage audio output of the amplifier is wired back to the 8373 and connected to up to three separate speaker zones using high current internal zone control relays. The zone control relays are activated appropriately prior to paging based on the SIP extension called, multicast IP address received, or keypad input. For scalability, multiple 8373 Paging Adapters can be used to support as many page zones as required from a single amplifier

Further speech enhancement is provided by automatic level control, choice of frequency masks, and optional speech compression. Output level is compatible with consumer, commercial, and pro-audio amplifiers requiring either -10 dBm, 0 dBm, or +4 dBu line level.

Multicast capability allows scalability for multiple amplifiers as well as integration with any combination of Algo IP speakers/strobes/adapters (e.g. 8128, 8180, 8186, 8188, 8301, 8373) in zoned and large scale applications.

What is the difference between the Algo 8373 and 8301 Paging Adapters?

Please contact Algo for application assistance.


  • Superb audio clarity and intelligibility – no hum or noise
  • Network managed and supervised SIP and multicast endpoint
  • PoE (802.3af) for plug and play network connectivity
  • Eliminates narrowband FXS port or ATA and zone controller
  • Multicasting capability for scalability to add more zone coverage and include other IP endpoints


  • Wideband G.722 codec support for HD Voice
  • Isolated and balanced audio output
  • Automatic level control
  • Internal zone control relays (3)
  • Multicast for cost effective scalability – mix with any number and variety of Algo speakers, strobes and/or paging adapters (e.g. 8128, 8180, 8186, 8188, 8301, 8373)
  • Multicast receive or broadcast capability
  • Polycom Group Page
  • SIP compatibility with all leading UC vendors including Avaya, Broadsoft, Cisco, Digium/Asterisk, Mitel, Metaswitch, NEC, and Polycom to name a few
  • Configurable through web interface
  • Auto-provisioning (i.e., TFTP, FTP, HTTP)
  • SNMP supervision
  • Multiple SIP registration for Page (50) extensions


  • IP phone system integration with legacy zoned analog amplifier (e.g. school, hospital, retail, etc.)
  • Hybrid voice paging solution to integrate analog speaker infrastructure and multicasting to IP endpoints

8373 Zone Paging Adapter Specifications

Item Description
Power Input 48 V PoE IEEE 802.3af Class 0 (Max 3.84W – Idle nominal 2.0W).
SIP Multiple page extensions available.
Multicast Transmit or receive using multicast IP address mapped to paging zone(s).
Codec Support G.711 A-law, G.711 u-law, G.722, Polycom Group Page.
Processor Linux OS; ARM Cortex-A8 32-Bit RISC Processor.
Line Output Low impedance balanced output. Line level -10 dBm / 0 dBm / +4 dBu. Transformer isolated internally. Male mini-XLR connector and pluggable terminal block. Frequency response 100-7000 Hz +/- 3dB.
Audio Memory 1 GByte.
Speech Processing ALC, filtering, compression.
Audio Delay Programmable 1-1000 ms synchronization delay.
Page Mode Live or delayed (cache and release).
Page Zone Based on SIP extension called, received multicast IP Address, or keypad events for 8373 configured as page SIP extension.
Relay Output Normally open or normally closed. Max rating 30 V 50 mA.
Configuration Web interface (HTTP or HTTPS) or autoprovisioning server.
Provisioning TFTP, FTP, HTTP
Supervision SNMP
NAT STUN, CRLF Keep Alive.
Environmental +32 to +122 deg F (0 to +50 deg C); suitable for dry indoor environments only.
Dimensions 6.5” x 4.3” x 1.3” (16.5 cm x 10.9 cm x 3.3 cm).
Mounting Wall mountable or tabletop.
Weight 2.2 lb (1.0 kg).
Compliance EN60950:2001, IEEE 802.3-2008, RFC3261, RoHS, CE, FCC Class A, CISPR 22 Class A, CISPR 24, CSA/UL (USA & Canada)

Note: In the interests of continuing product improvement, specifications are subject to change without notice.