The HMDC 27 Professional Broadcast Headset and Cable with NoiseGard from Sennheiser is a closed, circumaural ear-cup design that features active-noise reduction to perform well in very loud environments. It can be used by broadcast commentators and audio engineers to reduce the noise level by 15 dB and increase intelligibility, while at the same time protecting the user's hearing and avoiding stress and fatigue due to noise.
The headset does not run on batteries but is powered via the microphone's power supply (P48 phantom power) from the broadcast desk or intercom system. It is equipped with a two-piece headband that has no pressure on the sensitive fontanelle, and a wide headband padding is included that converts the two-piece headband into a compact single piece. In addition, an XLR and 1/4" cable is included.