Beyerdynamic’s HS 600 DANR offers 40 decibels of ambient noise attenuation, which combines both passive and active modes.
There still are a few older pilots who fly without headsets—and most have hearing damage as a direct result. For the rest of us, a decent headset is a key piece of safety equipment. Until just a few years ago, all headsets were passive, blocking out sound by clamping a small pair of cushioned speakers against the pilot’s head. This works, but getting good results requires a heavy headset and high clamping pressure, which can be uncomfortable. In the 1980s, another option became available: electronic noise-reduction headsets. They’re usually lighter—and, thus, more comfortable, especially on long flights—but less effective than conventional headsets when the noise reduction is turned off. Turn on the noise reduction, though, and engine noise drops dramatically. This happens because inside each earpiece is a tiny microphone that captures ambient noise, plus electronics that attempt to cancel that noise out.
Beyerdyamic, a German company with an 85-year history in designing and engineering audio products, has recently updated the HS 600 DANR (digital active noise reduction) aviation headset with its “version 2.0” advanced noise-reduction features. The company claims 40 decibels (dB) of “ambient noise attenuation” (combining both passive and active modes), compared with 21 to 27 dB for most passive headsets.
To understand that, you need to know that a decibel is a logarithmic measurement of sound pressure. Add 20 dB and you’ve increased the pressure by a factor of 10. That’s important because too much pressure can damage your ears. According to an FAA safety brochure, continuous exposure to sound levels of 90 dB or higher can produce permanent hearing loss. Average noise level in single-engine piston cockpits ranges from 70 to 90 dB, which is uncomfortably close to the limit. Conventional passive headsets cut this by 19 to 27 dB, which certainly helps, but they’re most effective at cutting high-frequency noise—and how well they work depends on how good a seal the earphone cushions provide against your head. Those of us who wear eyeglasses never get a perfect seal, so we tend to get less noise reduction. Even with a perfect seal, there’s still a low-frequency rumble that’s similar in pitch to human speech, so you still may have trouble understanding your copilot, passengers or ATC when it’s calling “traffic alert.” Electronic noise reduction filters out low-frequency noise and makes it easier to hear the intercom and radio. Most vendors who offer electronic noise reduction claim around 20 dB of additional noise reduction over and above the passive reduction offered by the earphone seal.
I tested Beyerdynamic’s HS 600 DANR on a local flight in a friend’s Cessna 180 (my airplane was down for maintenance). I found the headset generally quite comfortable, though the weight and clamping pressure were both a bit higher than a competing noise-reduction headset I’ve used for several years. In passive mode (with noise reduction off), the HS 600 DANR gave comparable results to the competition—but I was very impressed when I turned the noise reduction on. Low-frequency rumble from the engine almost disappeared, making voice communications easy to understand.
I compared the HS 600 DANR in flight with my older analog noise-reduction headset and a friend’s passive headset, and had him try the HS 600 DANR as well. We both agreed that the HS 600 DANR was the clear winner in cutting low-frequency noise. I also was delighted to find that the HS 600 DANR avoided a common problem with older analog noise-reduction headsets: feedback that sounds like a squeal during descent. That’s likely a benefit of the HS 600 DANR’s microprocessor-controlled, digital noise-reduction circuit.
Like all portable electronic noise-reduction headsets, the HS 600 DANR has a battery box and control unit, which in this case uses two AA batteries, and like all such units, it will happily flatten the batteries if you forget to turn the unit off. Thankfully, the HS 600 DANR includes an automatic switch-off function to save battery life. Still, Beyerdynamic uses a soft-touch on/off switch that’s easy to turn on by accident when handling the headset, so I recommend that owners remove the batteries when not in use. The HS 600 DANR battery box also includes jacks to connect a cell phone or music device and for external power.
On the plus side, the HS 600 DANR includes a volume control that works in both passive and active modes, which I found quite effective in finding an audio level that worked well for me and my friend, who was using a different headset. And I was pleased with the HS 600 DANR’s well-designed carrying case.
Beyerdynamic’s HS 600 DANR sells for $749 plus tax and shipping. It’s manufactured in Germany and serviced in Farmingdale, N.Y., and includes a five- year warranty. A wide range of customization options (mainly related to the color of various components) is available through the company’s website. Visit www.beyerdynamic-usa.com/aviation.