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.

• Active noise compensation (NoiseGard) additionally reduces noise by up to 15 dB. No batteries required: Power supply via microphone bias voltage from the commentator's unit
• The headset has a lightweight circumaural design with a split headband and provides no pressure on the sensitive fontanelle
• Accurate and linear sound reproduction for very demanding monitoring
• The dynamic microphone stands out due to a strong and powerful sound pattern. It delivers the audio transmission with a high-broadcast quality even in noisy environments
• ActiveGard (on/off switch) for protected hearing against noise peaks greater than 110 dB
• Modular concept of different cables and boom arms that offer the highest flexibility
• Cables of the 26-II series headphones are compatible
• Swiveling ear cap for single-sided listening
• Microphone can be worn either on right or left hand side
• Wide headband padding is included that converts the two-piece headband into a compact single piece