Bose ProFlight 2 Series Frequently Asked Questions Manual page 5

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FAQ Bose ProFlight Series 2 Aviation Headset
TECHNOLOGY FAQ
What is the latest technology in
the Bose ProFlight Series 2?
NOISE CANCELLATION FAQ
How much noise reduction does the
Bose ProFlight Series 2 provide?
What is the attenuation at
di erent frequencies?
What is the EPA-rated attenuation
of the Bose ProFlight Series 2?
How easy is it to hear other crew
members in a lower noise environment
with the headset on?
Does Bose o er noise cancellation in
helmets for aircraft or motorcycles?
For internal and reseller distribution only - Bose confidential
The ProFlight Series 2 includes a number of important technologies. The
most significant is the digital active noise cancellation earbuds, which o er
comparable active noise reduction performance provided by the
industry-leading Bose A20, but with less passive noise reduction. The
headset performs in loud environments and across a wide range of
frequencies with Bose proprietary microchip and microphones both inside
and outside each bud. The small electronics system better senses the sound
by more e ectively measuring, comparing and reacting to produce an
opposing cancellation signal. A proprietary eartip design provides additional
passive attenuation. The carefully selected materials of the headset eartip
block more noise from the ear and further improve comfort. The headset
features a high-performance microphone for communication, Bluetooth®
audio and a communications interface, all weighing in at just a fraction of the
weight of many competing aviation headsets.
The ProFlight Series 2 provides three di erent modes of user selectable noise
cancellation. Each mode is engineered for a distinct use.
"Low" optimizes interpersonal communication outside the use of an intercom
system. "Medium" provides consistent noise reduction across a wider range
of frequencies. "High" provides the greatest amount of active noise reduction,
maximizing the signal-to-noise ratio for radio communication.
Bose makes no claim about specific levels of noise reduction. Such numbers
cannot accurately describe what you will hear when using the product. We
encourage pilots to try the product in a variety of aircraft to experience the
dramatic performance and capability of each mode for themselves.
The current methods specified by the EPA Noise Reduction Rating (NRR)
cannot be applied to active noise cancelling devices, only passive devices.
That's why you see the NRR on traditional aviation headsets, but not on noise
cancelling aviation headsets. The EPA has for many years evaluated redefining
the NRR to include active noise cancelling devices in its scope, however, the
latest TSO guidelines call out ANSI test standards, which do relate to active
noise reducing aviation headsets, and to which Bose contributed to and
complies with.
Because active noise reduction technology excels at the lower frequencies
(below 1khz), the ProFlight Series 2 will not completely cancel voices. Essentially,
this means that in many situations, voices can be heard where they would
usually be completely drowned out by aircraft and wind noise. In addition, the
"low" mode of operation is designed to optimize communication outside the
use of the intercom. Tap control for talk-through communication puts the
tapped earbud into this low mode and improves directional hearing to this ear.
At this time, Bose does not o er active noise reduction within helmets.
But Bose conducts ongoing research to solve problems with unique
technology o erings.
AV I AT I O N
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