Sennheiser keeps the noise down for commentators
The three member 27 Series of broadcast headsets has been designed to comply with the EC directive on noise in the workplace. All three models include Sennheiser’s switchable ActiveGard function that reportedly protects the commentator against noise bursts. ActiveGard has been designed to detect noise peaks above 110dB, and compress the signal to this level, ensuring that any transmitted information remains fully comprehensible.
Taking this one step further, the HMDC 27 also features switchable NoiseGard active noise reduction. This technology reportedly increases intelligibility while also protecting the user’s hearing and avoids noise-induced stress and fatigue. The active noise reduction does not require batteries but is powered via the P48 power supply from the broadcast desk.
The other two members of the series are the HME 27 and the HMD 27. These differ in their microphone type. The HME 27 offers an electret microphone while the HMD 27 has a dynamic microphone. The mics for all three members of the series have again been designed with noisy environments in mind. The HME 27 has a pre-polarised condenser microphone with cardioid pick-up pattern (frequency response: 40Hz to 20kHz), while the HMD 27 and HMDC 27 possess a hyper-cardioid boom microphone with a frequency response of 40Hz to 18kHz.
The headphones have a stated frequency response of 8Hz to 18,000Hz and a THD below 0.1 per cent (measured at 1kHz, 100dB SPL). The cable has a small number of coils near the earcup that the manufacturer states acoustically decouples the headphones from handling noise.