NR à Go-Go
A sample article from the archives of the B.A.S. Speaker
by Michael A. Gendel (Maryland)

On recent business trips I had the opportunity to try out two noise-canceling headphones: the Noise Cancellation Technologies (NCT) NoiseBuster NB-EX ($79 srp) and the Koss Quiet Zone 2000 ($199 srp).

Each trip was in the coach section of a Boeing 737. During the outbound trip I sat in the last row (near the tail, which is the noisiest location); for the return flight I was in row 11 (just behind the leading edge of the wing, therefore not exposed to much engine exhaust noise) . As always, I wore MaxLite NRR-30 foam earplugs (from Howard Leight Industries) throughout the flights. [Actually, much of the noise near the tail of a jet is due to turbulent airflow over the fuselage. Nearer the nose of the aircraft, airflow is more nearly laminar and so quieter -- JSA]

NCT Outbound

I used the NCT headphones over the foam earplugs during the outbound flight. The NCTs were comfortable and easily adjustable. The belt clip on the processor box is a nice feature. The cord from the armrest to the box is of sufficient length to provide mobility without entanglement. The cord from box to headset is possibly a bit too long. I set the mode selector to the airplane icon, which reduced noise more effectively than the normal stereo position.

I listened primarily to the classical music and the air-traffic controller pilot/ground communications channels on the aircraft's entertainment system. Unfortunately, the classical channel's left-right separation was fouled up and it was difficult to get a good stereo signal. However, on all channels, the sonic improvement from using these headphones was impressive. Using the noise-canceling circuitry eliminated a significant amount of nasty engine noise, and generally resulted in a fuller sound regardless of content or source channel. The effect was quite dramatic. The level of nearby passenger talk was also reduced but not completely eliminated, which could be considered a plus, since total isolation could be a problem under certain circumstances.

On the negative side, I heard an annoying ringing effect when employing the noise-canceling effect.

Koss on the Return

I used the Koss unit, again over the foam earplugs, on a late-night return flight, after several grueling days of work. My fatigue may have negatively affected my evaluation of this unit.

The cord from the armrest to the box is too short for convenience. The signal processor box didn't fit well in my shirt pocket owing to the short armrest cord and the location of the cord connections on the box. The earphones are comfortable and adequately adjustable, although the headband had the annoying problem of catching and pulling out some hair every time I readjusted the headset. I again heard an annoying ringing when employing the noise-canceling effect.

I tried the Koss unit without also using the foam earplugs and found that it did eliminate much of the cabin noise but does not come close to the earplugs' effectiveness.

The flight attendant noticed the power LED on the processor box and insisted I turn it off during takeoff and landing, even though I tried to explain it was not generating computer or RF signals. I tested it surreptitiously, anyway, since these are the noisiest parts of a flight, and appreciated having the unit.

Comments

The Koss signal processor box is larger, bulkier and heavier than that of the NCT. That box lacks the belt clip, so it was harder to find a convenient and stable place for it. The Koss headphones are more comfortable and adjustable than the NCT.

The ringing sensation from the NCT was slightly more objectionable than from the Koss unit.

The Koss unit enhances the audio much better than the NCT unit-the Koss unit gave me a fuller, more ambient sound.

With each unit, I tried cupping my hands over the ear pieces to get a tighter fit, and got an annoying squeal [feedback, presumably-DRM] with the Koss unit that I did not get with the NCT.

A bit more spring in the NCT headband would help improve the sound quality without producing a headache.

Overall, the Koss produced a better sound, but its ringing was more of a distraction than the NCT. The cord and box of the NCT are preferable to those of the Koss.

Clearly, seat location is the most effective antidote to flight noise, with foam earplugs second. However, just as ambient noise reduction reduces the stress associated with occupying a small space in a steel tube for a significant amount of time, so, too, does the use of active cancellation benefit the flyer to the extent that it further reduces the tiring, draining noise so prevalent in an airplane cabin, while also allowing one to listen to music or some other possibly comforting signal.

Anything that helps the passenger relax is well worth the expense to the frequent traveler.


 

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updated 11/11/04