What About Intercoms?

[It didn't take long for Thursday's article on ANR headsets to generate some thoughtful feedback. Here's an early letter, pointing out yet another aspect of 'cockpit sound system' choice, from somebody who knows what he's talking about. The mic design and shielding, and proper placement, are all important, as well -- the hearing side is only as good as the input side, you know. It's like discussing supply and demand -- there's two sides (or 'garbage in, garbage out,' in more-colloquial terms) --ed.]

Hello ANN,
I just finished reading your [preview of your] review on the top-of-the-line ANR headsets, and, as
an intercom manufacturer, thought I would add my two cents' worth.

As you found out, ANR headsets are good for noise reduction in the low frequency spectrum; but beyond that point, they become your basic passive or acoustic headsets. In some cases, [they're] not as good as a well-designed passive-only headset.

Now, take that $900 headset and plug it in... and what happens?  Everything the headset's boom microphone picks up that is above the ANR range is passed through the intercom and to the headphones every time the VOX is open. That means the wind noise, passengers' talking and the, "Ah, Ah," to get the squelch to open are heard. This is not a good combination: high-tech headphones plugged into voice-operated intercom, a technology that has roots back to the 1950s.

With technology comes improvements -- and after making voice-operated intercoms since 1993, we developed a better way to communicate. In 1999, we introduced what we call the Enhanced Noise Reduction Intercom technology, no squelch circuits, no squelch knobs, no background noise, just talk.

Enhanced Noise Reduction is not to be confused with the ANR headsets -- it will not improve a passive headset -- but what it will do is eliminate the sounds that are picked up by the headset's microphone and heard through a VOX intercom. That means the wind noise, talking, and other cockpit noises are not heard. In fact, sound levels up to 110db that would be heard through a voice-operated intercom are eliminated.

Another major advantage of the Enhanced Noise Reduction technology is the fact that the microphones are always active while canceling the background noise. The benefit is no "Ah, Ah" when starting to talk, and no popping audio. The pilot and passengers can carry on a normal conversation without the VOX TALK speech pattern.

The question is often asked, "Will ENRI replace an ANR headset? No; it picks up where ANR [sets] leave off. Will it improve the noise reduction of my passive headset?  No; what you won't hear is everything you have been hearing on your VOX intercom.

My two cents' worth. --Joe Fisher (Owner, FlightTech Intercoms)

FMI: www.flighttech.com