Sennheiser HMDC 27

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

 

Impedance 64 Ohms
Frequency Response 40 Hz to 18 kHz (microphone)
8 Hz to 18 kHz (headphones)
Transducer Principle Dynamic (microphone)
Dynamic, closed (headphones)
Microphone BMD 434
Maximum Sound Pressure Level (SPL) ActiveGard Limiter off: 128 dB SPL @ 1 kHz
ActiveGard Limiter on: 110 dB SPL @ 1 kHz
Contact Pressure Approximately 3.3 N
Ear Coupling Circumaural
Pick-up Pattern Hyper-cardioid
Microphone Sensitivity 0.5 mV/Pa @ 1 kHz
Maximum Sound Pressure Level (SPL) 128 dB SPL @ 1 kHz (passive)
ActiveGard 110 dB SPL @ 1 kHz
Distortion < 0.1% @ 1 kHz, 100 dB SPL
Dimensions Not specified by manufacturer
Weight 8.5 oz (240 g) without cable