The Bell Ultra Digital Intercom Amplifier (BEL2140052) is the amplifier unit for Bell and Zeronoise intercom systems and is also compatible with any Peltor-compatible helmet that uses Nexus plugs. It uses digital signal processing to separate speech from background noise, operating through three selectable noise-cancelling filter settings that can be cycled by a switch designed for use with racing gloves, or adjusted remotely via a WiFi connection from a service laptop or phone.
Each of the three filters is calibrated for a different noise environment. The principle is that mechanical and wind noise have different frequency profiles across circuit, rally and hillclimb events; choosing the correct filter for the day’s conditions rather than applying a single fixed setting improves speech clarity at both ends. Bell and Zeronoise publish filter guidance for their common event types in the product documentation.
A Bluetooth connection to a mobile phone allows co-drivers and navigators to take calls on road sections without removing the helmet. This is useful in rally use where a road section may follow a stage with no opportunity to stop.
The amplifier is compatible with Bell intercom helmets and any Peltor-compatible helmet using a Nexus connector. It is not a stand-alone radio unit and requires a radio transceiver in the car for race-to-pit communications. If you are building an intercom system from scratch and want to check which helmet, cable and amplifier combination works for your car before ordering, speak to us first.
