Issue 89 - May 2014
In the communications world there are many ways to get audio from point A to point B and for each different application that’s arisen, suitably niche products have been developed. At Sonifex we’re a company that specialises in developing niche products for niche applications, as evidenced by the growing Redbox range, mainly developed as audio and video ‘glue’ to piece together the larger elements of an audio/video installation.
We took a step into the ‘comms’ world 3 years ago with the release of a dedicated 1U rackmount 4-wire/IFB talkback intercom unit. For use in OB trucks, TV production galleries, audio booths and backstage theatre comms, the CM-TB8 offers 8 channels of 4-wire communications with 2 IFB circuits. It has the usual features of: individual channel level controls, speaker with mute and dim functions, headphone output, mic/headset input with phantom power, etc, but it also has some interesting additions.
The unit has a built in line-up tone generator for easy channel identification and cabling checks. This allows a much simpler installation since each output can be individually recognized on connection.
It has an Ethernet port so that it can be configured from a web-browser and altered on-the-fly from a remote location, or just more simply from a desk position, rather than having to go to the front panel of the rack. It also allows new user features to be added simply.
The most recent unique addition to the controller is the ability to add a dual GSM or dual POTS (telephony) card into the unit so that you can have 6 channels of 4-wire/IFB and 2 channels of either GSM/POTS/IFB connectivity. This allows a cameraman, interviewer, commentator or anchorman to be in a remote location and still receive talkback, and talk to the producer, over GSM (Note: without the need for expensive wireless equipment, which for one channel can cost as much as the CM-TB8 itself). Whilst it doesn’t offer a totally wireless solution, it does provide a cheap half way house to allow comms over a non-wired connection.
The GSM modules have separate antenna connections on the rear panel and are configured via the embedded web server. This provides access to features including network selection, telephone number storage and phone logs. Telephone calls are made and received directly on the CM-TB8 using the channel controls to speed dial the required telephone number. IFB modes are fully supported on the telephone channels allowing selected input signals to be routed to a connected telephone call.
For more information on the CM-TB8, go to: http://www.sonifex.co.uk/cmtb8/
