DirectOut Technologies EXBOX.RAV

Ravenna is an open-standard AoIP technology offering low latency and high reliability and can operate on existing network infrastructures. It has been widely adopted for broadcast applications and is fully compatible with the provisions of AES67 and SMPTE standards ST2110-30 and ST2110-31, and also with AMWA’s NMOS specifications IS-04 (Discovery and Registration API) and IS-05 (Device Connection management API).

EXBOX.RAV may be used with globcon software, a powerful application which can control any combination of DirectOut products through a simple, standardised GUI. globcon is available in Mac and Windows versions, and is downloadable free of charge from www.globcon.pro.

EXBOX.RAV can convert up to 64 audio channels (in up to 32 streams/Flows) between Ravenna and MADI formats, in both directions simultaneously. An internal 256 x 256 routing matrix allows totally flexible audio channel routing between all inputs and outputs, while the software’s “Port View” permits an entire Ravenna or MADI stream to be patched from one port to another. A built-in web server permits the matrix to be easily accessed via a browser. globcon additionally allows snapshots of frequently used routing configurations to be saved for subsequent recall, minimising setup time.

No setup is required other than selection of the appropriate clock source via the web browser or globcon. EXBOX.RAV incorporates DirectOut’s FastSRC™ on the Ravenna inputs. FastSRC has been developed to minimise rigging time: it allows multiple multichannel audio devices to be interconnected without any immediate concern regarding synchronisation. Once the system is up and running, FastSRC may be disabled if desired, for a fully transparent audio path.

Front panel LEDs indicate which input streams are active and locked, and also which is acting as the current clock master. All standard sample rates are supported from 44.1 kHz to 192 kHz, +/-12.5 kHz; further LEDs confirm the rate in use. All common MADI formats are also supported: 48k and 96k Frame, 56/57/64 channels, plus S/MUX.

Three types of MADI port are fitted: i) optical – a dual SC socket for connection of multimode fibre optic cable (singlemode available as a time-of-order factory upgrade); ii) coaxial – two BNC sockets (input and output); iii) an unpopulated SFP cage for the user’s own choice of cartridge, which may be either optical multimode or singlemode, or coaxial. Port selection is defined as part of the internal matrix configuration.

Network connections are via four gigabit Ethernet ports (RJ45s): two are intended for the AoIP network and two for control purposes (via browser or globcon), though port functions may be reconfigured in software. An advanced method of timestamping is applied to PTP sync data to give improved synchronisation accuracy.

EXBOX.RAV features DirectOut’s EARS (Enhanced Automatic Redundancy Switching) system, which gives the user the highest possible level of playback or connection resilience. EARS  uses DirectOut’s proprietary BLDS trace tone, inserted synchronously onto Channel 32 of a pair of multitrack recorders. In the event of failure of the primary signal, EARS automatically switches between Channels 1-32 and Channels 33-64 in an inter-sample gap, resulting in a completely seamless output. If more than 32 channels of Ravenna are in use as a single stream, EARS can be configured to switch between Ravenna and MADI sources. Where multiple 64-channel streams are in use – as with redundant operation – a second EXBOX.RAV may be employed to convert the secondary Ravenna stream to MADI, allowing EARS changeover of up to 64 channels in the event of primary stream failure. EARS is configured through a simple web page, where the engineer has full control over how the redundancy switching function should operate. If a BLDS tone is unavailable, EXBOX.RAV will perform the same redundancy switch function using any audio tone >-40 dBFS as a pilot-tone; in this case, switching is achieved within 10 – 15 ms.

Two locking Hirose connectors allow connection of one or two external DC PSUs (one supplied as standard). Alternatively, if preferred, the unit may be powered via PoE (Power-over-Ethernet). As with other units in the DirectOut EXBOX series, the unit is 1U high and one-third rackwidth wide. An optional mounting kit is available enabling EXBOX.RAV to be mounted in a 19” rack, either alone or with one or two other EXBOX or MA2CHBOX.XL units.