The inclusion of a 3.5-milimeter headphone jack supports integration into existing hearing aids, offering a range of up to 100 meters in which users can receive streaming audio. Stereo sound is individually adjustable for those who experience varying levels of hinderance, with three different hearing settings available based on incoming content type. Volume is adjusted via a large ergonomic dial found on the front of the unit, with three additional channels available to ensure maximum wireless signal strength. Auto-tuning is provided for frequently-accessed television channels and radio stations, enabling simplistic configuration for faster content access. The 840 S can function for up to 9 hours on a single battery charge, with an additional charging compartment included within the transmission unit for non-stop access.
