HAI Convention News

Garmin reveals digital audio panel

 - March 6, 2011, 12:30 AM

Garmin yesterday unveiled the GMA 350 series digital audio panel for helicopters and fixed-wing applications, with two unique new features for aviation, voice-recognition controls and 3D audio. The new GMA 350 series fits in a box that is pin-compatible with Garmin's GMA 340 series and also audio panels made by other manufacturers. The GMA 350H and 350 are similar, but the helicopter unit includes support for a third com, NVG-compatible green annunciation and new split-com modes.

The new features, said Garmin engineer and test pilot Sean Doyle, “are all about reducing pilot workload and improving safety.” The 3D audio function mimics the way humans process audio, delivering a more natural-sounding result to stereo headphones. Based on research done at the Massachusetts Institute of Technology, 3D audio spatially separates two different audio inputs. With current audio panels, if a pilot is listening to ATC on one radio and ATIS or weather on another, it is difficult to separate the two audio streams. With 3D audio, each channel is separated and piped towards opposite sides of the headphones. During a demonstration of the GMA 350H, I found that 3D audio is much more like hearing multiple conversations and being able to pick out which one I wanted to hear. Switching back to ordinary 2D audio highlighted the differences. And back on 3D audio, I was easily able to pick out which audio stream to focus on and which one to ignore, but they weren't stepping over each other like in 2D audio. “It's kind of subtle,” Doyle said. Garmin has demonstrated 3D audio with three audio streams, he added, “ and that's incredibly impressive because you really can listen to any one of those three conversations.”

Voice-recognition technology allows the pilot to control all of the GMA 350 audio panel's functions with voice commands instead of pushing buttons on the panel. To let the panel know that a voice command is coming, the pilot first has to click a trigger switch, which will likely be on the yoke or cyclic, then speak the command. For example, saying “com 1” switches the radio being monitored, and saying “com1 mic” changes the transmitting radio.

Another new GMA 350 feature is “blue mode,” which allows for independent routing of audio to passengers or pilots and also independent control of volume levels for each audio source. An LED volume indicator bar graphically shows volume levels, so if a back-seat passenger asks for a little bit more volume on the intercom, the pilot can easily see how much to add. The GMA 350 also allows passengers to control their intercom isolation state. This eliminates the need for a passenger to ask the pilot to turn on the passenger's intercom channel.

Split com lets the front-seaters select which com each person can use, adding flexibility to the cockpit. With a three-com radio setup, for example, the pilot can select com 1 and 3 and the copilot com 2 or pilot com 1 and copilot com 2 and 3. The GMA 350 also offers audio-leveling. As ambient noise increases, the audio panel automatically boosts the sound like the systems on car stereos that play louder as a car speeds up and generates more ambient noise.

Other features include pilot, copilot and 4/5-passenger stereo intercom, two stereo music inputs, front panel music input jack, five unswitched audio alert inputs for external warning tones and a clearance recorder for playback of the mic-selected com.  Retail price of the GMA 350 is $2,395, and the GMA 350H with helicopter-specific features is $2,695.