Bose Aviation Headset X User manual

The Bose
®
Aviation Headset X
Owner’s Guide

2
Safety Information
We, the offerer:
Bose
®
Corporation,
The Mountain, Framingham, MA 01701-9168 USA
Acknowledge our sole responsibility, that the product:
Kind of equipment: Bose Aviation Headset X
Type Designation: AHX-02, AHX-03, AHX-04, AHX-05,
AHX-06, AHX-07, AHX-08
is in compliance with the following norm(s) or document(s):
EMC-directive 89/336/EEC
Accredited test laboratory:
Mikes Product Service GmbH, Ohmstrasse 2-4, D-94342
Stasskirchen, Germany
EC Certificate of Conformity #: E9 99 03 14490 008,
TCF#: Z16260
Bose Products B.V. Nic Merks
Nijverheidstraat 8, 1135 GE Edam Vice President Europe
The Netherlands Manufacturer’s authorized
EU representative
5 April 1999

3
Cautions and Advisories
Operational advisory
The Bose
®
Aviation Headset X, an active noise reducing (ANR) headset,
is a complex electronic device. As with any complex device, it is
possible for this headset to fail during operation. Failure may include
loud tones, distortion, and loss of communications signal in the
headset when used in the ANR mode. The headset includes redundant
circuitry to reduce the effects of such failures.
Note : Such failures could prevent continued use of the headset in the
ANR mode.
The headset is in the ANR mode when the control module power
switch, shown in Figures 5 and 6, is set to ON. The headset is in the
passive mode when the power switch is set to OFF.
If you experience loud tones and the related loss of communications,
turn off the power switch. The headset will continue to provide com-
munications in the passive noise attenuation mode.
If you own a battery powered headset, it should be connected only to
the battery power. An aircraft powered headset should be connected
to the aircraft power sources only as described in this guide. The
aircraft powered headset will not operate properly if used with a Bose
Series II battery pack or with any commercial battery pack.
Hearing safety
Note : The headset is intended to be used with ANR turned on. Noise
reduction and communications performance are reduced with the
headset turned off.
Volume control
The volume controls affect the volume of the communications signal
coming into the headset whether the ANR is on or off. As pilot in
command, you must ensure that with ANR off you can understand
critical communications. You may need to turn up the aircraft commu-
nications system volume when the headset is turned off. The aircraft
communications system volume control should be easily accessible.
Avoid setting the volume controls at levels high enough to impair your
hearing during extended periods of headset use.

4
Cautions and Advisories
Listening to your aircraft
With the headset’s combination of both active and passive attenuation,
typical aircraft sounds (for example, those from engines, propellers,
warning alarms, and other sound sources) may sound different to you.
We strongly recommend that, as a responsible pilot, you ensure that
you can hear and recognize these sounds when using the Bose
®
Aviation Headset X while operating any aircraft.
Entertainment audio sources
In addition, should you choose to listen to in-flight entertainment
through a Bose Aviation Headset X while piloting, we remind you to
limit the volume to safe levels that do not interfere with your ability to
hear informational sounds and warning alarms, such as stall warnings
or gear up.
Cautions
Protective inner screen
The protective inner screen, shown in Figure 1, is a component critical
to the headset’s ability to reduce noise. Do not attempt to remove,
replace, or repair this screen. If operating problems indicate the need
for screen replacement, contact the Bose Aviation Headset Depart-
ment. If the screen becomes wet or if foreign objects become lodged
on or adjacent to it, proceed as described in General Care and Mainte-
nance.
Earcup TriPort™ maintenance
Proper headset operation requires that the earcup TriPort openings be
kept free of debris. The TriPort openings, shown in Figure 1, are
located on the outside of each earcup and are comprised of two holes
and a screen.
Storage
Do not store the headset in an unventilated area or in direct sunlight. If
the headset is battery powered, remove the battery before storing the
headset for extended periods.

5
Cautions and Advisories
Water damage
Do not attempt to use or repair the headset if it has been immersed in
water. Contact the Bose
®
Aviation Headset Department for assistance.
See the inside back cover for address information.
Chemicals
Certain chemicals may harm the headset. Seek information about
specific chemicals from the chemical manufacturers.

6
Contents
Safety Information .................................................................................................. 2
Cautions and Advisories
Operational Advisory ..................................................................................... 3
Hearing Safety ............................................................................................... 3
Cautions ........................................................................................................ 4
Introduction
Headset introduction ..................................................................................... 8
Headset description ...................................................................................... 9
Common features .................................................................................. 9
Boom microphone cable variations ....................................................... 9
Boom microphone cable variation table.............................................. 10
Preparing the Bose®Aviation Headset X
Preparing the Bose Aviation Headset X for use ......................................... 11
Attaching or relocating the boom microphone cable ................................. 11
Detaching the boom microphone cable
or connector access cover .................................................................. 11
Attaching the boom microphone cable ............................................... 12
Attaching the connector access cover ................................................ 12
Warranty card ....................................................................................................... 12
Using the Bose®Aviation Headset X
Wearing the Headset................................................................................... 13
Microphone Placement ............................................................................... 14
Operating the battery powered headset ..................................................... 14
Power switch........................................................................................ 14
Control module mounting clip ............................................................. 14
Stereo/mono switch ............................................................................. 15
LED power indicator ............................................................................ 15
Volume control ..................................................................................... 16
Volume control using multiple headsets.............................................. 16

7
Contents
Operating the installed headset .................................................................. 17
Power switch........................................................................................ 17
Volume control ..................................................................................... 17
Volume control using multiple headsets.............................................. 18
Control module mounting clip ............................................................. 18
Aircraft panel connector ...................................................................... 18
Installing the aircraft panel connector ................................................. 19
General Care and Maintenance
Instructions for continued airworthiness..................................................... 23
Cleaning Instructions ........................................................................... 23
Replacing the ear cushion ................................................................... 25
Replacing the wind screen .................................................................. 26
Replacing the battery ........................................................................... 26
Replacing the headband cushion ........................................................ 27
Replacing the boom microphone cable or connector access cover .. 27
Troubleshooting
In case of difficulty ...................................................................................... 28
Technical Information........................................................................................... 30
FAA technical standards order ................................................................... 31
Service and warranty Information
Ordering spares and accessories ............................................................... 32
Warranty period ........................................................................................... 32
Service ......................................................................................................... 33

8
Headset introduction
Congratulations on purchasing the Bose
®
Aviation Headset X. This
headset uses advanced electronic noise reduction circuitry and
acoustical design to reduce aircraft noise. The headset reduces noise
with only slight headband clamping force, and it can be worn comfort-
ably for extended periods.
You may have a battery powered version of the Bose Aviation
Headset X, or an installed version. The illustrations in Figure 1 show
the two different headsets.
Figure 1
Headset components
battery-
powered
control
module
mounting
clip
adjustable
headband
protective
inner screen
ear cushion
flexible
microphone
boom
wind
screen
Introduction
Earcup TriPort™
openings aircraft
installed
control
module

9
Introduction
Headset description
The Bose
®
Aviation Headset X comes in several variations for both
general aviation and helicopter use. These variations are defined by the
configuration of the attaching cable and the headset’s power source.
Common features
Headsets have the following features (see Figure 1).
• Acoustic Noise Cancelling
®
earcups
• An adjustable headband
• Replaceable ear cushions
• A flexible microphone boom with positional adjustment
• A replaceable wind screen
• A cable with an integrated control module
• A control module mounting clip (battery powered version)
• A cable-mounted clothing clip (installed version)
• A replaceable fleece headband cushion
Boom microphone cable variations
All boom microphone cables assemble into the headset as described
in Preparing the Bose Aviation Headset X on page 11. Depending upon
the headset configuration purchased, the boom microphone cable will
be one of the types described in the Boom microphone cable variation
table on page 10.

10
Use Power Cable Microphone Plug Controls
Source Type
Battery Straight Electret Standard • ON/OFF switch
(9V) headphone • Volume control
and • Stereo/Mono switch
microphone • LED power indicator
Aircraft Straight Electret For aircraft • ON/OFF switch
(10-32V) panel • Volume control
connector (dual thumb wheel)
Aircraft Coiled Electret For aircraft • ON/OFF switch
(10-32V) panel • Volume control
connector (dual thumb wheel)
Battery Coiled Electret U174 • ON/OFF switch
(9V) • Volume control
• LED power indicator
Battery Coiled Dynamic U174 • ON/OFF switch
(9V) low • Volume control
impedance • LED power indicator
(10-32V) Straight Electret For aircraft • ON/OFF switch
Aircraft panel • Volume control
connector (dual thumb wheel)
H
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A
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Introduction
Boom microphone cable variation table
Note: You will need to verify the type of headset connection required
by your aircraft communications panel before choosing a configuration
from the table below.

11
Preparing the Bose
®
Aviation Headset X
Attaching or relocating the boom microphone cable
Detaching the boom microphone cable or connector access cover
If necessary, remove the boom microphone cable or the connector
access cover from the earcup as follows:
1. Loosen the two captive screws using a flat-tipped
screwdriver (see Figure 2).
2. Pull the cable or the cover away from the earcup in a
direction parallel to the screw axes.
Note: Do not twist the boom microphone cable while disconnecting.
Twisting can damage the connector pins.
Preparing the Bose Aviation Headset X for use
Most Bose headsets are shipped with the boom microphone cable
attached. Some headset configurations are shipped with the cable
packed separately in the shipping container. All headset configurations
allow the boom microphone cable to be attached to either earcup, at
the user’s option.
Figure 2
Attaching the boom
microphone cable
connector
access
cover
boom
microphone
cable loosen screws
several turns

12
Preparing the Bose
®
Aviation Headset X
Attaching the boom microphone cable
Attach the boom microphone cable to the earcup as follows:
1. Ensure that the cable connector and the mating earcup
connector are clean and free of debris.
2. Retract the headset to its fully-closed position and ensure
the earcups are together.
3. Place the cable into position.
4. Ensure that the cable connector is properly aligned with
the earcup connector pins. If not aligned properly, damage
may result.
5. Gently push the connector until it is fully engaged and
the cable is seated against the earcup. Do not apply
excessive force as earcup damage may result.
6. Ensure that the screw threads are properly started and
tighten screws.
7. Rotate the microphone boom into the proper position.
8. Test headset operation before flight.
Attaching the connector access cover
Attach the connector access cover to the earcup as follows:
1. Place the connector access cover into position.
2. Ensure that the screw threads are properly started and
tighten screws.
Battery
If your headset is battery operated, install a fresh 9-volt alkaline battery
into the control module, as described in General Care and Mainte-
nance on page 26.
Warranty card
The Bose Aviation Headset X comes with a warranty card. Please
supply the requested information to help Bose provide you with
advisories and updates. Copy the serial number, located beneath the
headband cushion, onto the warranty card and mail it to Bose.

13
Using the Bose
®
Aviation Headset X
Wearing the headset
User comfort and good noise reduction performance require a proper
fit. Note the left and right earcup markings and place the headset on
the head as shown in Figure 3. Lightly grasp both earcups and position
them so that your ears are completely inside the ear cushions and you
feel even, gentle pressure around your ears. Adjust the headband to
rest gently on top of your head.
Final adjustment is best made in a noisy environment with the power
switch set to ON. See Figures 5 and 6 for details. Experience using the
headset helps establish a sense of how it should sound. When using
the headset in very loud conditions, as during takeoff, you may experi-
ence brief reductions in ANR as the headset compensates for a
momentary pressure change. If there is a problem, refer to Trouble-
shooting. If the problem persists, contact the Bose Aviation Headset
Department for assistance.
Note: A low rumbling sound or frequent brief losses of ANR may
indicate an improper fit or blocked earcup ports. See General Care
and Maintenance.
If during a long flight you feel a slight pressure point, adjust the
headband position to restore comfort.
Figure 3
Wearing the headset

14
Using the Bose
®
Aviation Headset X
Microphone placement
Clear communications depend on proper microphone placement.
Follow these three steps for proper placement:
1. Identify the left and right earcups and put on the headset.
2. While holding the boom pivot in place, grasp the boom with your
fingers and move the microphone housing to your mouth.
Note: Make sure the microphone is positioned with its label side
closest to the mouth. Do not purse your lips. The microphone should sit
slightly off center, but right at the opening of your mouth.
3. Once the microphone is in place, make sure the plastic housing
with the printing is perpendicular to the lips. For clearest communi-
cations, make sure the microphone is as close as possible to your
lips – you should feel the windscreen brushing your lips as you
speak.
Figure 4
Microphone placement
Operating the battery powered headset
Power switch
Turn on active noise reduction by setting the power switch to ON. See
Figure 5 for details.
Note: If you are connecting the headset to a newly installed aircraft
powered system, remove the headset from your head before turning it
on for the first time, in case of high-volume output.
Control module mounting clip
The control module mounting clip permits attachment to the user’s
clothing, safety harness, or aircraft door pockets. Do not attempt to
clip onto surfaces greater than
1
/
4
-inch thick. You may attach a Velcro
pad to the face of the clip for attachment to other surfaces.

15
Operating the battery powered headset (cont.)
Stereo/mono switch
The stereo/mono switch is provided only on the general aviation,
battery powered headsets.
The battery powered versions of the headset are shipped from the
factory in the MONO setting. If your audio or intercom communications
system is in stereo, be sure to set the switch to stereo (see A in
Figure 5).
Figure 5
Battery powered
control module:
A. Stereo/mono switch
B. ON/OFF switch
C. Volume control
D. LED power indicator
LED power indicator
The LED, located on the control module, indicates power status as follows:
LED Color LED Illumination Indication
Green Blinking Power ON or battery normal
Red/Green Blinking Battery low (less than 5 hours use remaining)
Off None Power OFF or battery discharged
Using the Bose
®
Aviation Headset X
A
C
B
D
To headset
To communications/
audio panel

16
Using the Bose
®
Aviation Headset X
Operating the battery powered headset (cont.)
Volume control
Control of the volume level of the Bose Aviation Headset X requires
adjustments at both the aircraft intercom or radio and at the headset
control module. Avoid setting the volume levels too high. Exposure to
loud sounds may cause hearing damage.
Note: The headset volume control cannot completely turn off the
volume.
The headset volume control is located on the control module, as
shown in Figure 5. The volume at each earcup is controlled indepen-
dently. Adjust the volume as follows:
• Push-in and release the knob. It will pop up from the
control module.
• To increase the volume for the earcup with the boom
microphone cable attached, rotate the knob clockwise.
• To increase the volume for the other earcup, gently pull-out
the knob until you feel a click, and rotate the knob
clockwise.
To secure the earcup volumes at the selected levels, push-in the knob
flush to the control module.
Volume control using multiple headsets
When an aircraft has more than one headset connected to its audio
system, the pilot in command should adjust the volume of his/her
Bose Aviation Headset X as follows:
1. Turn off active noise reduction by setting the power
switch to OFF.
2. Set the volume on both earcups to maximum.
3. Adjust the aircraft intercom or radio master volume to hear
communications clearly. This should be done in noise.
Adjust the headset volume controls only to balance the
volume between the left and right earcups.
4. Turn the headset ON.
5. Turn down the aircraft intercom or radio master volume to
the desired listening level.

17
Operating the installed headset
Power switch
Turn on active noise reduction by setting the power switch to ON. See
Figure 6 for details. For volume control, follow the instructions in
Volume control below.
Figure 6
1. Power switch
2. Volume controls
Volume control
Control of the volume level of the Bose Aviation Headset X requires
adjustments at both the aircraft intercom or radio and at the headset
installed control module.
Note: Avoid setting the volume levels too high. Exposure to loud
sounds may cause hearing damage. The headset volume control
cannot completely turn off the volume.
• Turn on the power switch located on the control module.
• Set the aircraft communication system to a safe
operating level.
• Set the volume levels for the left and right earcups
by rotating the thumb wheels as needed.
Note: The microphone and cable assembly can be attached to either
earcup. Thumb wheel #1 will always control the volume level of the
earcup with the microphone and cable assembly attached. Thumb
wheel #2 will always control the volume level of the earcup without the
microphone and cable assembly attached.
Note: If you are connecting the headset to your aircraft for the first
time, turn down the master output level of your radio/intercom system
to avoid exposure to high volume levels.
Using the Bose
®
Aviation Headset X
2
1

18
Using the Bose
®
Aviation Headset X
Operating the installed headset (cont.)
Volume control using multiple headsets
When an aircraft has more than one headset connected to its audio
system, the pilot in command should adjust the volume of his/her Bose
Aviation Headset X as follows:
1. Turn off active noise reduction by setting the power
switch to OFF.
2. Set the volume on both earcups to maximum.
3. Adjust the aircraft intercom or radio master volume to hear
communications clearly. This should be done in noise.
Adjust the headset volume controls only to balance the
volume between the left and right earcups.
4. Turn the headset ON.
5. Turn down the aircraft intercom or radio master volume to
the desired listening level.
After the pilot’s headset volume is adjusted, passengers may adjust
their headset volume to the preferred level.
Control module mounting clip
The control module mounting clip permits attachment to the user’s
clothing, safety harness, or aircraft door pockets. Do not attempt to
clip onto surfaces greater than
1
/
4
-inch thick.
Aircraft panel connector
For permanent installation of the headset, the cable is installed into the
aircraft. A connector and 6-foot wiring harness are packaged with the
headset. The 6-foot wiring harness is a self-latching, precision de-
signed, quick-connector for panel mounting in the aircraft. The con-
nector is mechanically keyed to ensure proper mating.
Additional connectors and wiring harnesses are available from Bose.
To order, call the Bose Aviation Headset Department.
Note: The aircraft panel connector must be mounted by mechanics
qualified to perform this type of avionics installation into the aircraft
being used.

19
Figure 7
Connector technical
information
Using the Bose
®
Aviation Headset X
PIN 6
PANEL HOLE REQUIRED
AIRCRAFT INTERFACE SCHEMATIC
RED
•
1 V+IN
BLK
•
2 GND
WHT
•
3 COMM L
BLK
•
4 COMM R
WHT
•
5 MIC HI
WH/BLU
•
6 MIC LO
BLK
BLK
12.6mm
.5"
14.1mm
.56"
RECEPTACLE - PINOUT (FRONT VIEW)
PIN 1
Operating the installed headset (cont.)
Installing the aircraft panel connector
Mount the connector into a cutout, as shown in Figure 7. Connect the
eight wires as follows:
• Two for the microphone
• Two for audio
• One for power
• One for ground
• Two for audio shields
Audio and microphone wires should be connected to the back of the
existing microphone and headphone jacks, leaving existing jacks intact
for use with conventional headsets. This is usually the fastest installa-
tion method (see Figures 8 – 10 for reference).

20
Using the Bose
®
Aviation Headset X
Notes
• For use with a stereo intercom, connect the left and right
channels to their respective positions. For monaural operation,
connect pins 3 & 4 together to the tip of the existing phone jack.
• Do not use excessive force or bend the installed connector. This
may damage or break internal solder joints.
• If the boom microphone works on radio transmit but not through
the intercom, check pin 6. It may be incorrectly wired to the PTT
segment of the microphone jack.
• The wires connecting pins 3 & 4 and pins 5 & 6 are shielded,
twisted pairs with a shield termination exiting with a black wire for
each pair. Connect shields to existing audio wiring shields or to
audio ground, if existing wiring is not shielded.
• Connect shield from Comm L and Comm R wire pair to audio
ground.
The pinout for the optional installed connector is:
1 Red Headset power (10-32 VDC). Use a
1
/
4
-amp fuse or a
1
/
2
-amp circuit breaker.
2 Black System ground. Connect to the existing audio ground.
3 White Phone communication-L
4 Black Phone communication-R
5 White Microphone/Hi-audio. Connect to the portion of the
existing microphone jack that corresponds to the ring
position of a headset microphone plug. Do not
connect to the tip (PTT) segment.
6 White/Blue Microphone/Lo-ground. Connect to the portion of the
microphone jack that corresponds to the barrel
position of a headset microphone plug.
Comm Shield Black Shield from Comm 1 and Comm 2 wire pair
Mic Shield Black Shield from Mic Hi and Mic Lo wire pair
Pin Wire Color Description