The network audio adapter shall be able to convert analog audio signals to high quality digital signals for the purpose of non interrupted broadcast of audio over IP based networks such as LAN, WAN or Internet with full-duplex of mono signals being possible with 24-bit analog to digital and digital to analog converters operating at a sample rate of 48kHz. The device shall have a frequency response of 50 Hz - 18 kHz. The network interface shall be 10BASE-T/100BASE-TX, full-duplex/half-duplex Auto-negotiation Network Protocol: TCP, UDF, ARP, HTTP, RTP, IGMP, FTP, NTP The unit shall be able to connect up to 500 additional units via LAN and WAN and being able to establish up to 1,000 links.
The network audio adapter shall be capable of both Unicast and Multicast transmissions and a single audio input can be streamed to a maximum of 16 outputs (Unicast) or 64 outputs (multicast).
There shall be 2 audio input channels, balanced (transformer isolated/unbalanced changeable) offering LINE/MIC, changeable with volume adjustment. Rated input: -20 dB* (LINE)/-60 dB* (MIC) PAD function (-16 dB*) via removable 6 pin terminal block. There shall be 2 audio outputs channels, balanced (transformer isolated), 600 ohms or less Rated output: 0 dB* (unbalanced input) /-2 dB* (balanced input), also with 6 pin removable terminal block.
The control inputs shall include 8 channels, no-voltage contact input, open voltage:24V DC, short-circuit current: 2 mA or less with 9 pin removable terminal block.
The control inputs shall be individually programmable to initiate and terminate stored transmissions without the need for dedicated PC-based or other control equipment.
Broadcast priority can be set with 8 levels of priority allowing paging to override alert tones or announcements.
The network audio adapter shall be cable of storing internally up to 8 WAV-files with up to 2 minutes duration for broadcasting. It shall be possible to update the files remotely using the supplied software or web browser. Adjustable output volume of a broadcast can be set based on a programmed scheduler. The time of the device is automatically adjusted by NTP (Network Time Protocol) via the network.
Failure of one unit shall not affect other units within the system even if there is accidental power-down.
The network audio adapter shall include surveillance for monitoring any malfunction and failures. Any accidental power-down will not affect the activity log recordings. Activity logs shall be archived by means of inserting an SD/SDHC card (Max. 32 GB) from the front panel and up to 10,000 logs can be stored.
The supplied software shall be simple with intuitive GUI (Graphic User Interface) allowing full control, with system configuration and settings. Maintenance shall be made possible among distributed devices. The front panel shall include, audio input, signal (green)/peak (red), 2 channels, audio output, signal (green) link active (green), busy (green), status (green), error (yellow), run (green).
Power requirements shall be 24 VDC (plug-in screw connector) or an optional AC adapter. The finish shall be 30% black gloss pre-coated steel plate, and the dimensions shall be 210 x 44.3 x 258 mm (8.27” x 1.74” x 10.16”) weighing 1.7 kg (3.75 lb.)

*0 dB = 1V

Optional extras: AC power supply AD-246, rack mount bracket for 1 unit MB-15-BK,
rack mount bracket for 2 units MB-15-J manufactured by TOA Corporation