Sennheiser upgrades broadcast headset with new HMD 26 series

At the 2010 NAB Show, Sennheiser introduced its new HMD 26 broadcast headset series, designed as a next-generation upgrade to the firm’s HD 25 model. The HMD 26 is designed specifically for broadcasters operating in high-noise environments such as live sporting events. In an exclusive interview on the show floor, Sennheiser product manager Jörg Buchberger explained the rationale behind the new design.

“In making a new product to replace a very successful model like the HD 25, we knew we had to be very careful,” Buchberger said. “We went directly to our customers, both in Europe and the U.S., and asked them questions — what they liked about the HD 25 and how it could be improved. In fact, I moved from Germany to America for one year to make sure our R&D department got the correct feedback.”

Research indicated several major areas of concern: voice pickup by the microphone, audio feed to the earphones, reliability/serviceability and user comfort. The HMD 26 addressed all these concerns with from-the-ground-up design changes. “But that was only the first step,” Buchberger said. “When we came up with the first prototypes, we went back to our customers and presented the product for field testing. It was when we finally reached the point where all the feedback was positive that we decided to launch the product.”

To address sound quality, Sennheiser developed a new dynamic capsule for the HMD 26. The capsule features a hypercardioid pickup pattern with noise compensation to help ensure consistent response characteristics across a wide range of mic-to-mouth positions. “Our goal was to provide a linear frequency response from the capsule, regardless of how the boom is situated by the user. Obviously, you cannot control user behavior on microphone positioning. The challenge for our R&D group was to provide consistent sound in all situations, and it seems we have succeeded in that,” Buchberger said.

“When we tested the product at the NCAA Basketball Championship with CBS, we had one announce with his mic set very close to his mouth, and the other had the boom quite far away to the side,” Buchberger said. “The audio engineer was very impressed. He said, ‘Look, I just take the original sound, did nothing with the equalizer and just transmit it!’ And both mics sounded very good. I think that’s the best feedback we could hope for from a broadcast engineer.”

On the monitoring side, Sennheiser has equipped the HMD 26 with dynamic headphone speakers capable of providing high SPL, with response out to 16kHz. The earcups were also redesigned, using very soft, high-quality foam beneath a supple leatherette material. The issue of comfort was addressed with Sennheiser’s dual-band, automatic-opening headband that evenly distributes pressure and by reducing the headphone’s net weight to a mere 7.1oz.

Reliability was addressed in several ways, most notably in the cabling and electrical connections. Unlike its predecessor, the HMD 26 has no exposed wiring, with all audio pathways neatly contained within the headband itself. In addition, the cable is now field replaceable, with a modular cable design requiring only a screwdriver, allowing easy repairs as well as the ability to accommodate different connector requirements.

The HMD 26 is available in several variations including a single-ear version and the option for a phantom-powered, cardioid condenser mic element. “Our goal was to give our customers the product they wanted; to create a new headset design that sounds good on the air, is comfortable and sounds good in the announcer’s ear; and is less likely to fail in the field,” Buchberger said. “Judging by all the positive feedback we have received, we believe we have succeeded.”

The Sennheiser HMD 26 series of headsets is now shipping.