Bose 416317 User Manual

®

Bose® A20

Aviation Headset

Owner’s Guide

Important Safety Information

Please read this guide

Please read this owner’s guide carefully. Save this guide for future reference and make it easily accessible for passengers and third
parties who use the headset.

Safety Warnings:

• Turn the headset off if it emits any loud noise.

As with any complex electronic device, it is possible for this headset to fail during operation. Symptoms of failure, which
may include loud tones, distortion, feedback squeals and loss of communications signal in the headset, can occur in
either the Acoustic Noise Cancelling
loud noise and the related loss of communications in the Acoustic Noise
The headset will continue to provide communications in the passive noise reducing mode. If the problem persists, see
Troubleshooting on page 30.

•

Switch to an alternate communications method in the event of a headset issue.

In the unlikely event of any headset issue or failure in the passive noise reducing mode, switch to an alternate
communications method and use standard cockpit resource management skills to minimize distractions.

•

Be aware of sound differences while wearing the headset.

With the headset’s active and passive noise reduction, typical aircraft sounds (such as from engines, propellers, and

stall or gear up warnings) will not sound familiar on your rst few ights. Such important sounds may be quieter than you

are used to. You are responsible for making sure that you can hear, notice and recognize these sounds when using the
headset while operating any aircraft.

•

Use the headset at a moderate volume level.

To avoid hearing damage, use the headset at a comfortable, moderate volume level. Limit the headset 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, while piloting.

•

Do not make phone calls while piloting.

During ight operations, do not use the headset for telephone calls.

•

Make sure your aircraft communications system volume control is easily accessible.

Make sure you can understand critical communications even with Acoustic Noise Cancelling turned off. We recommend
that you set the audio system volume so that you can understand radio communications in passive mode, in full aircraft
noise, then use the control module’s volume controls to set a comfortable level with Noise Cancelling on. In passive
mode, the control module will automatically switch to maximum volume. If your headset is aircraft powered, connect the
headset to the aircraft power sources only as described in “Connecting the headset to the aircraft” on page 13.

•

Make sure portable devices do not interfere with the aircraft’s navigation and communication systems.

It is a pilot’s responsibility to ensure that portable devices do not interfere with the aircraft’s navigation and communica­tion systems, as well as to determine if the portable device is suitable for use with the Bose

•

Make sure AUX source volume is turned up.

If the AUX source audio volume is set at a low level, it may be below the detectable threshold or may cut in and out.

•

Do not use the headset with a helmet or as part of a crash protection system.

The headset is not intended for such use, and has not been certied for crash protection. Dismantling, reassembly
or modication of the headset, or any part, for use in a helmet or other crash protection system could result in severe

bodily injury and such unauthorized use will void the limited product warranty.

•

Use only AA alkaline batteries.

Replace the batteries only with AA alkaline batteries (IEC LR06). There is a danger of explosion if batteries are incor-

rectly replaced with any other battery chemistries. Batteries may cause a re or chemical burn if mishandled. Do not

recharge, disassemble, heat, or incinerate batteries. Dispose of used batteries properly, following any local regulations.
The headset will not operate properly if used with any battery source other than the Bose A20 Aviation Headset control
module.

•

Keep batteries out of reach of children.

®

mode (turned on) or in the passive mode (turned off). If the headset emits any

Cancelling mode, turn of

f the power switch.

®

A20® Aviation Headset.

WARNING: Contains small parts which may be a choking hazard. Not suitable for children under age 3.

WARNING: This product contains magnetic material. Contact your physician if you have questions on whether

this might affect the operation of your implantable medical device.

This symbol means the product must not be discarded as household waste, and should be delivered to an
appropriate collection facility for recycling. Proper disposal and recycling helps protect natural resources,
human health and the environment. For more information on disposal and recycling of this product, contact
your local municipality, disposal service, or the shop where you bought this product.

China Importer: Bose Electronics (Shanghai) Company Limited, Part C, Plan 9, No. 353 North Riying Road, China (Shanghai)

Pilot Free Trade Zone

EU Importer: Bose GP, Castleblayney Road, Carrickmacross, Ireland
Taiwan Importer: Bose Taiwan Branch, Room 905, 9F, Worldwide House, 131 Min Sheng East Rd, Section 3, Taipei, Taiwan, 105

2 - English

Important Safety Information

Cautions Regarding Maintenance and Repair:

• Do not repair the headset yourself.

Do not attempt to remove, replace, or repair the protective inner screen on the inside of the earcup, which is critical to
the headset’s performance. If screen replacement or other repair seems necessary, contact Bose Technical Support.
See “Contact information” on page 39. If the screen gets wet or any foreign objects become lodged on or adjacent to it,
follow the instructions in “Headset Care and Maintenance” on page 25.

Keep the earcup free of debris.

Proper headset operation requires that the headset TriPort® and microphone openings located on the outside of each
earcup are kept free of debris to ensure clear communications. See “Cleaning the headset” on page 26 for cleaning
instructions.

Regulatory Information

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC
Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This
equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruc­tions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a
particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by
turning this equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Re-orient or relocate the receiving antenna.

•

Increase the separation between this equipment and receiver

• Connect this equipment into an outlet on a circuit different from that to which the receiver is connected.
Consult Bose or an experienced radio/TV technician for help.

•

Changes or modications not expressly approved by Bose Corporation could void the user’

This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions: (1) This device may not
cause harmful interference, and (2) this device must accept any interference received, including interference that may cause
undesired operation.

This device complies with FCC and Industry Canada RF radiation exposure limits for general population. It must not be collocated
or operating in conjunction with any other antenna or transmitter.

Operate this product within the temperature range of 5°F to 131°F (-15°C to 55°C) only.

Bose Corporation hereby declares that this product is in compliance with the essential requirements and other
relevant provisions of Directive 1999/5/EC and all other applicable EU directive requirements. The complete
declaration of conformity can be found at: www.Bose.com/compliance.

Toxic or Hazardous Substances and Elements

Part Name Lead (Pb) Mercury (Hg) Cadmium (Cd)
PCBs X O O O O O

Metal parts X O O O O O

Plastic parts O O O O O O

Speakers X O O O O O

Cables X O O O O O

Names and Contents of Toxic or Hazardous Substances or Elements

This table is prepared in accordance with the provisions of SJ/T 11364.
O: Indicates that said hazardous substance contained in all of the homogeneous materials for this part is below the limit requirement of

GB/T 26572.
X: Indicates that said hazardous substance contained in at least one of the homogeneous materials used for this part is above the limit
requirement of GB/T 26572.

Date of manufacture: The rst underlined digit in the serial number indicates the year of manufacture; “5” is 2005 or 2015.

.

s authority to operate this equipment.

Hexavalent

(CR(VI)) Polybrominated Biphenyl (PBB)

Polybrominated

diphenylether (PBDE)

Please complete and retain for your records:

The serial number can be found underneath the headband cushion.
Serial number ______________________________________________________________________________
Purchase date _____________________________________________________________________________
We suggest you keep your receipt with this owner’s guide.

The Bluetooth® word mark and logos are registered trademarks owned by Bluetooth SIG, Inc., and any such use by Bose Corporation is under license. All
other marks are property of Bose Corporation.

©2015 Bose Corporation. No part of this work may be reproduced, modied, distributed, or otherwise used without prior written permission.

English - 3

Contents

Introduction ......................................................................................... 6

About your Bose® A20® Aviation Headset .......................................................................... 6

Our commitment to you ........................................................................................................ 6

What’s included ....................................................................................................................... 6

Components .............................................................................................................................7

Control module variations ............................................................................................ 8

Power and cable variations........................................................................................... 9

Preparing the headset for use .......................................................... 10

e microphone assembly ...................................................................................................10

Attaching the microphone assembly ........................................................................10

e battery compartment .................................................................................................... 11

Opening the battery compartment ............................................................................ 11

e operation switches ................................................................................................. 11

Changing the operation switches ............................................................................... 11

Auto On .................................................................................................................... 12

Auto Off ..................................................................................................................... 12

Inserting and replacing the batteries ........................................................................ 13

Connecting the headset to the aircraft ............................................................................. 13

Using the 6-pin plug ..................................................................................................... 13

Using the dual general aviation plugs.......................................................................14

Using other plug types ................................................................................................. 14

Using the headset ............................................................................... 15

Wearing and adjusting the headset ...................................................................................15

Conditions related to fit ............................................................................................... 15

Microphone placement ................................................................................................ 16

Clothing clips ................................................................................................................. 16

Using the control module .................................................................................................... 17

Power button ................................................................................................................. 17

Power indicator ..............................................................................................................18

Intercom volume controls ...........................................................................................18

Primary and secondary audio sources .............................................................................. 19

AUX audio sources (wired) ................................................................................................... 19

Bluetooth

4 - English

®

audio sources (wireless) .................................................................................. 19

Using the headset with a Bluetooth

®

device ..........................................................20

Pairing the first device ..........................................................................................20

Pairing another device ........................................................................................... 21

Switching between connected devices ............................................................... 21

Bluetooth

®

multi-function button ....................................................................... 21

Making and answering calls ................................................................................ 22

Reconnecting to a previously connected device .............................................. 23

Contents

Recovering a lost connection ...............................................................................23

Disconnecting a Bluetooth

Clearing the headset pairing list ......................................................................... 23

Controlling Bluetooth

In-call muting..........................................................................................................23

Secondary audio modes ...................................................................................................... 24

Secondary Audio Mode selector ................................................................................ 24

Managing multiple secondary sources .................................................................... 25

Setting the Priority (BT-AUX) switch .................................................................. 25

®

device ....................................................................23

®

volume ...........................................................................23

Headset care and maintenance ........................................................ 26

Instructions for continued airworthiness ........................................................................ 26

Cleaning the headset ........................................................................................................... 26

General cleaning ........................................................................................................... 26

Headset earcup openings ........................................................................................... 26

Microphone windscreen .............................................................................................. 27

Earcup inner screen ..................................................................................................... 27

Headband cushion ....................................................................................................... 27

Replacing parts ..................................................................................................................... 27

Microphone windscreen replacement ...................................................................... 27

Ear cushion replacement ............................................................................................28

Battery replacement .................................................................................................... 28

Headband cushion replacement ...............................................................................29

Microphone assembly or terminator cover replacement .....................................29

Storage ...................................................................................................................................29

Troubleshooting ................................................................................. 30

Installation ........................................................................................... 35

Mounting the aircraft panel connector ............................................................................ 35

Technical information ........................................................................ 36

Mono connection diagram ..................................................................................................36

Stereo connection diagram ................................................................................................36

Helicopter (U174) connection diagram ............................................................................. 37

Details on making the connections .................................................................................. 37

FAA Technical Standards Order..........................................................................................39

Warranty and service information ................................................... 40

Locating the headset serial number .................................................................................40

Limited warranty service ....................................................................................................40

Contact information ..............................................................................................................41

Ordering parts and accessories .......................................................................................... 41

English - 5

Introduction

About your Bose® A20® Aviation Headset

With the Bose® A20® Aviation Headset, you can rely on crisp, clear audio and
significant noise r
the headset to secondary audio sources such as smartphones or tablets.

eduction for all cockpit communications. You can also connect

Our commitment to you

We take great pride in designing each of our products with the goal of provid­ing the highest performance possible in the price range of that product. We strive
to reproduce the musical sounds as closely as possible to those of the original
performance. And we strive to avoid flashy sounds such as those associated with
accentuated bass and/or treble frequencies. While those sounds may be initially
attractive to the novice, they are not real and are not enduring. In addition, we use
only the highest-quality parts and the latest assembly and quality control tech­niques to ensure the reliability and long life of our products.

Our reputation rests on our steadfast pursuit of this policy in music and entertain­ment systems for the home, the automobile, and businesses. At Bose, we are
committed to investing in research that continually gives rise to new technologies
for improving sound reproduction.

When you purchase any product from Bose, we encourage you to compare it, as
we do, to competitive products. We believe that this process will enhance your
appreciation of the product you select. With best wishes from all of us at Bose for
many years of enjoyment.

What’s included

The headset includes a control module, cable, and carrying case.

The type of control module and connector configuration depends on the options
you chose for your headset.

There are two options for the control module:

• Control module with Bluetooth

•

Conventional contr

There are several end-plug configurations for the headset. Your headset falls into
one of two general categories:

• Battery powered: Operates with battery power only.

• Dual powered: Operates with either aircraft or battery power. No battery needed
when connected to aircraft power. This version is often called Flex powered and
comes with an Auto On function.

ol module

®

compatibility

6 - English

Components

Headset

Clothing clip

Introduction

Carrying case

2 AA alkaline
batteries*

Control module

See “Control module
variations” on page 8
for options

3.5 mm AUX audio cable

Second
clothing clip

Cable connector (varies)

Note: Cable connector types will vary based on model of headset. See “Power and

cable variations” on page 9.

Warning: * Replace batteries with alkaline batteries only. Do not use any other

battery chemistries.

English - 7

Introduction

Control module variations

If you purchased the Bluetooth version of the headset, you received the Bluetooth
control module. If not, you received the conventional control module.

Bluetooth

Bluetooth
indicator

Bluetooth
multi-function
button

Secondary Audio
Mode selector:

Mute
Intercom
prioritized over
secondary
sources

Mix
Intercom
mixed with
secondary
source(s)

Off

Intercom only

®

control module Conventional control module

Left/Right

Intercom Volume controls

Power indicator

Power button

Bluetooth
Volume Up button

Bluetooth
Volume Down button

Auxiliary (AUX)

audio input

Secondary Audio
Mode selector:

Mute
Intercom
prioritized over
secondary
sources

Mix
Intercom
mixed with
secondary
source(s)

Off

Intercom only

Note: When the Secondary Audio Mode selector is in the Mute or Mix position,

you will hear a maximum of two audio sources – the intercom plus one
secondary source. See “Secondary Audio Mode selector” on page 24.

8 - English

Introduction

Power and cable variations

The Bose® A20® Aviation Headset is available for purchase in different standard
aircraft connector options, including:

Battery powered options

Operate with battery power only

Dual G/A 6-pin*

U174 5-pin XLR

U384 8-pin

Dual powered options

Operate with either aircraft or battery power
No battery needed when connected to aircraft power

* An adapter is available from Bose to convert a 6-pin connector to a dual G/A or

U174 plug for additional connection flexibility.

Note:

Many dif

ferent combinations of control module, microphone, connector
and cable types are available. Contact Bose Technical Support for more
i nformation.

English - 9

Preparing the Headset for Use

e microphone assembly

Your headset may be shipped with the microphone assembly (boom microphone
and cable) attached to the left earcup. If you prefer, you can switch it to the right
earcup.

If your headset is shipped with the microphone assembly packed separately, you
can attach it to either earcup.

Attaching the microphone assembly

Choose the earcup (L or R) where you want to attach the microphone assembly.
Also, make sure that the earcup connector pins are clean and free of debris.

1.

Use a Phillips scr
near the bottom of the earcup where you want to attach the microphone
assembly.

2. Remove the terminator cover to reveal the connector pins on the earcup.

3.

efully line up the microphone assembly to the small connector socket on

Car
the earcup.

4. Slide the connector into the socket until it reaches the stop.

ewdriver to loosen the two screws on the terminator cover

L (left)

Terminator
cover

Connector
pins

Microphone
assembly

Connector pins

Caution: Do not force the connector into the socket, or earcup damage may

occur.

5. Tighten the screws to secure the assembly.

6. Attach the terminator cover to the earcup that does not have the microphone

assembly attached. Insert the screws, then align and tighten them.

Note: The headset will not work without the terminator cover installed.

Caution: Be sure to try the headset and fully test its operation before flight.

10 - English

Preparing the Headset for Use

AUTO OFF

ON - OFF

AUTO ON

ON - OFF

e battery compartment

The headset is shipped with factory-set operation defaults. If you want to alter
these defaults, you can change the operation switches located inside the control
module battery compartment.

Opening the battery compartment

Press down firmly on the finger indent and slide the cover down. The cover is
tether

ed to the module. Do not attempt to detach it.

Note: The battery compartment cover is designed to remain securely closed. You
may need to use extra force when pressing down and releasing the cover.

e operation switches

The operation switches control: Priority (BT-AUX); Intercom (MON-ST); Auto On
feature; and Auto Off feature. For details see the table on page 12.

• The Auto On feature is only
available for aircraft powered
versions.

• The Intercom (MON-ST)
option is only available for
headset configurations that
support two-channel or
stereo intercom systems.

ON - OFF

AUTO ON

AUTO OFF

ON - OFF

The Priority (BT

•

-AUX)
option is only available for
Bluetooth

headsets.

Changing the operation switches

1. Open the battery compartment.

2. If batteries are installed, remove them. In the battery compartment, you can

observe and change the switch positions.

3. To change a switch position, use a pen or a small, flat-tipped screwdriver to
gently move the switch.

English - 11

Preparing the Headset for Use

This table shows possible positions, default setting, and purpose for each
operation switch.

Operation Switch Purpose

PRIORITY

(Available for

Bluetooth

headsets only)

INTERCOM

(Available
for headset
configurations
that support
two-channel or
stereo intercom
systems only)

AUTO ON

(Available for
aircraft powered
headset versions
only)

AUTO OFF

®

Establishes priority between two secondary audio
sources. Select BT to give the Bluetooth (wireless)
connection higher priority. Select AUX to give the wired
connection higher priority.

See “Setting the Priority (BT-AUX) switch” on page 25.

For most configurations, set at the factory for mono
audio systems (to provide audio in both ears).

Set it to stereo (ST) if your aircraft has a stereo intercom.

Set at the factory to enable the Auto On function. The
headset will turn on when aircraft power is available.

To disable Auto On, set the switch to OFF. With the
switch in OFF position, the user must manually turn the
headset on.

Set at the factory to enable the Auto Off function.
The headset will turn off after three to nine minutes of
inactivity.

To disable Auto Off, set the switch to OFF. With the
switch in OFF position, the user must manually turn the
headset off.

Auto On

With aircraft powered versions (5-pin XLR, 6-pin, and 8-pin) the headset will turn
on automatically when aircraft power is available. If you do not want the headset to
turn on automatically, set the switch position to OFF.

Auto Off

The Auto Off feature detects when the headset is not in use and shuts it off after
several minutes to preserve battery power. The exact time it takes to shut off varies
and can range between three to nine minutes after you stop using the headset.

When the headset is running on battery power and is not plugged in to a
intercom, it will shut off, unless there is an active AUX audio source present.

If you are on a phone call and unplugged from the intercom, the headset will allow
you to complete your call, then it will turn off approximately three minutes after the
call is ended.

12 - English

power

ed

Preparing the Headset for Use

Inserting and replacing the batteries

Caution: If the batteries do not fit correctly, do not force them in. Forcing an

1. Turn off headset power.

2. Press down firmly on the battery compartment cover and slide the cover to

3.

4.

Warning:

Note: For air

impr

oper connection will cause permanent damage to the control

module.

release. The battery door is tethered. Do not detach the door from module.

Insert two alkaline AA batteries into the contr
polarity.

Replace the battery compartment cover

Replace batteries with alkaline batteries only
battery chemistries.

craft-powered versions (5-pin XLR, 6-pin, 8-pin) batteries are not

required for operation if aircraft power is available.

ol module, observing proper

.

. Do not use any other

Connecting the headset to the aircraft

The headset can be configured to either plug into aircraft power or rely entirely on
battery power.

Using the 6-pin plug

A single 6-pin plug inserted into the 6-pin connector provides the headset with
aircraft power and intercom audio.

If your headset is aircraft-powered, a 6-pin connector may be installed and mount­ed to an aircraft panel. See “Mounting the aircraft panel connector” on page 35.

Note: An adapter is available from Bose to convert a 6-pin connector to a dual G/A

or U174 plug for additional connection flexibility for users who fly multiple
aircraft and require other connector types.

To connect the headset

Align the 6-pin plug to the connector keyway by matching the narrow bar on the
plug to the slot on the connector.

Firmly press the plug into the connector jack.

Align keyway

Push plug in

English - 13

Preparing the Headset for Use

To disconnect the headset

1. Pull back on the sleeve near the end of the 6-pin plug.

Gently continue pulling back to r

2.

Caution:

Pull sleeve back, then pull plug out

Do not pull the connector out without first pulling back the sleev
Forcing the connector out will damage the cable and/or the aircraft
instrument panel.

Sleeve

emove the plug from the connector.

e.

Using the dual general aviation plugs

The most common battery powered (only) version of the headset has two general
aviation (G/A) plugs that connect to the aircraft audio. Although the plugs look
similar, the microphone plug is shorter, thinner, and has a slightly different shape
than the intercom plug.

Insert the thicker intercom plug in first. It will only fit into one of the jacks.
Then insert the thinner microphone plug into the other jack.

Microphone

Intercom/Audio

Using other plug types

The headset is also available with other types of plugs for connecting to various
aircraft audio jacks. These single-plug connectors should be inserted into the ap­propriate jack on your aircraft control panel. Refer to “Power and cable variations”
on page 9.

14 - English

Using the Headset

Wearing and adjusting the headset

Proper fit on your head is important both for comfort and optimal noise reduction
performance. Here are a few guidelines:

Use the left (L) and right (R) markings above the ear

•

properly.

R

L

160º

• The microphone is intended to rotate no more than 160° as shown above. Do not

force the microphone beyond the intended rotation.

•

As you put the headset on, lightly grasp each ear
is completely over your ear. You should feel an even, gentle pressure all around
each ear.

• Adjust the headband so it rests gently on top of your head.

• Make your final adjustments with the headset powered on in a noisy

environment.

In very loud conditions, such as during takeoff, you may experience a brief reduc­tion in Acoustic Noise Cancelling

®

as the headset compensates for a momentary
pressure change. If the problem continues when the sound level returns to normal,
see “Noise reduction” on page 30. If the problem persists, contact Bose Techni­cal Support.

cups to orient the headset

cup and adjust it so its cushion

Conditions related to fit

A low rumbling sound or frequent, brief losses of Acoustic Noise Cancelling noise
reduction may indicate an improper fit or blocked earcup ports. See “Headset
earcup openings” on page 26 for instructions on removing blockages.

During a long flight, you may feel a slight pressure point, which can be relieved by
adjusting the headband position. Your experience with using the headset will help
establish a sense of how it should sound and feel.

English - 15

Using the Headset

Microphone placement

Microphone placement is important for clear communications. With the headset on
your head, make these adjustments:

Grasp the boom with your fingers and move the micr

1.

is level with your mouth.

Pull the micr

2.

ophone in toward your lips. Position the microphone with its talk
side facing in (indicated by label). Though it will be slightly off center, the
microphone should be 1/2 inch from the opening of your lips.

Mic label

Mic is 1/2 inch
from mouth

3. Make sure the talk side of the microphone is facing your lips. Do not purse
your lips.

ophone up or down so it

Clothing clips

The control module cable is fitted with two clothing clips. Use the clips to attach
the headset cable to your clothing, a safety harness, or an aircraft door pocket.

Press to open clip

Press to release and reposition
clip along the cable

16 - English

Using the Headset

Using the control module

If you purchased the Bluetooth® version of the headset, you received the Bluetooth
control module. If not, you received the conventional control module.

Bluetooth

Bluetooth
indicator

Bluetooth
multi-function
button

Secondary Audio
Mode selector:

Mute
Intercom
prioritized over
secondary
sources

Mix
Intercom
mixed with
secondary
source(s)

Off
Intercom only

®

control module Conventional control module

Left/Right

Intercom Volume controls

Power indicator

Power button

Bluetooth
Volume Up button

Bluetooth
Volume Down button

Auxiliary (AUX)

audio input

Secondary Audio
Mode selector:

Mute
Intercom
prioritized over
secondary
sources

Mix

Intercom
mixed with
secondary
source(s)

Off

Intercom only

Power button

Action What to do

Turn on the headset

Turn off the headset

Dim the power and
Bluetooth indicators

Press

Press and hold

Note: When powered off, the headset will still provide pas-

sive audio communications.

Note: Repeated pressing will not speed up the power off

event. If the unit does not power off, wait 3 seconds
try again.

Press

once.

for three seconds.

twice quickly. Repeat to brighten.

English - 17

Using the Headset

Power indicator

New alkaline AA batteries will generally supply at least 45 hours of power for the
headset. Battery life varies with the ambient noise level of the aircraft, temperature,
ear cushion condition, use of the Bluetooth
power indicator changes color to indicate the power status, as follows:

®

feature, and age of the batteries. The

Indicator
color

Green Aircraft Slow flashing Power ON

Green Battery Flashing Power ON and batteries good

Amber Battery Fast flashing Power ON, but batteries low

Red Battery Very fast

Off None None Power OFF or batteries depleted

Power
source

Type of light Indicates

(8 hours or less remaining)

flashing

Power ON, but batteries very low*
(2 hours or less remaining)

Warning: Replace batteries with alkaline batteries only. Do not use any other

battery chemistries.

*When the batteries reach this level, the Bluetooth feature is disabled to conserve
remaining power. You will hear a tone, indicating that your Bluetooth device is
being disconnected and the Bluetooth feature is turning off.

Intercom volume controls

The left and right volume control wheels on the control module adjust the intercom
volume of the corresponding earcup. With Acoustic Noise Cancelling
control will be set to the maximum level.

Caution: Avoid setting the volume levels too high. Exposure to loud sounds may

cause hearing damage.

Holding the control module upright and facing you:

Use the left wheel to adjust volume of the left ear

•

Use the right wheel to adjust volume of the right ear

•

cup.

cup.

Overall headset volume control requires adjustments at both the aircraft intercom
or radio, and at the headset control module. Even at its lowest setting, neither
volume control wheel can completely turn off the volume.

®

off, volume

18 - English

Using the Headset

Primary and secondary audio sources

The aircraft intercom system (ICS) is always the headset’s primary audio source.
When the headset is plugged in to the aircraft, intercom signals will always be
heard and cannot be muted by the headset.

In addition to the primary source (intercom), the headset can connect to secondary
audio sources.

Secondary sources can be either AUX (wired) or Bluetooth

Only one secondary sour

Note:

source will never override intercom communications.

ce can be heard at a time. Audio from a secondary

®

(wireless).

AUX audio sources (wired)

Use the 1/8 inch (3.5 mm) AUX audio input to connect your headset with an exter­nal audio source such as a portable GPS or a portable audio device. The connector
is located at the bottom end of the control module as shown.

Use the supplied 1/8 inch (3.5 mm) adapter cable to connect your external audio
device. Plug one end of the adapter cable into the headphone plug on your device
and the opposite end into the headset AUX audio input.

AUX audio input

Note: None of the functions of a connected AUX source are controlled by the

control module.

Note: Audio from an AUX source will not be heard if the Secondary Audio Mode

selector is in the OFF position.

Bluetooth® audio sources (wireless)

If you purchased the Bluetooth control module version, you can wirelessly
connect your headset to an external audio source such as a smartphone or tablet.

English - 19

Using the Headset

Using the headset with a Bluetooth® device

Pairing the first device

1. Press to turn on the headset.

Make sur

2.

(not OFF).

The power indicator glows green or yellow, depending on the charge level of
the battery. (If the light is red, the battery is low and needs replacing.)

The Bluetooth indicator flashes purple to indicate that the headset is in pairing
mode.

Note: The first time you turn on the headset, it will automatically go into

3. Locate the Bluetooth menu on your device and make sure the Bluetooth

feature is ON.

4. Select Bose A20 from the Bluetooth device list.

e the Secondary Audio Mode selector is in the MUTE or MIX position

MUTE MIX

pairing mode and the Bluetooth indicator will flash purple. This will only
happen the first time you turn on the headset.

Bose A20

The Bluetooth indicator flashes blue while the devices are pairing, and a tone
indicates successful connection.

Note: After five minutes of inactivity, the headset will automatically exit pairing

mode and the Bluetooth indicator will turn off. To turn the Bluetooth
feature back on, press

Note: Each time you turn on the Bluetooth feature, the headset will attempt

to reconnect with the two most recently connected Bluetooth devices.
If the device(s) are turned off, or out of range, the headset will return to
pairing mode after five minutes. See “Reconnecting to a previously con­nected device” on page 23.

20 - English

.

Using the Headset

Pairing another device

The headset can pair with up to eight devices. To pair another device:

1. Press and hold

The Bluetooth

Bluetooth indicator

Bluetooth

multi-function
button

for one second to put the headset into pairing mode.

®

indicator flashes purple.

2. Locate the Bluetooth menu on your device and make sure the Bluetooth
feature is ON.

3.

Bose A20 from the Bluetooth device list.

Select

The Bluetooth indicator flashes blue while the devices are pairing.

Note: The headset will automatically exit pairing mode after five minutes of

inactivity.

Switching between connected devices

• The headset can connect to two Bluetooth devices at a time. Only one

connected device can be heard at a time.

• To switch between two connected Bluetooth devices, pause audio on the first

device and start audio on the other.

• To confirm connection, check the Bluetooth device list on your device.

Note: Incoming and outgoing phone calls automatically mute all other secondary

audio sources (when the Secondary Audio Mode selector is in either the
MUTE or MIX position). During a Bluetooth phone call, the intercom and the
phone call will be heard as mixed.

Bluetooth multi-function button

Action What to do Bluetooth indicator

Turn the Bluetooth
feature on

Turn the

Bluetooth

feature off

Enter pairing mode

Press

once.

Note: The first time you turn
on the headset, the Bluetooth
feature will be on and the headset
will be in pairing mode.

Press and hold

for five

seconds.

Press and hold

for

one second.

Flashes blue

Off

Flashes purple

English - 21

Using the Headset

Making and answering calls

Call activity What to do

To make a call Dial from your connected phone. The call will automatically

To activate voice control
(if available)

To answer a call

To end a call

transfer to the headset.

When there are no active or incoming calls, briefly press

Briefly press
before you hear the incoming call.

Briefly press . You should hear two short beeps in the
headset to indicate that the call has been ended.

. You should hear a short beep in the headset

.

To ignore an incoming call

To redial the last number

To transfer the audio to
the mobile phone

Press

When there are no active or incoming calls, press
quick succession.

When you are on a call, press
This transfers the audio to the mobile phone handset while the

Bluetooth® connection remains active.

for one second.

twice in

for three to four seconds.

Note: Some functions may not be available for some devices. Refer to your device

user’s guide for further details.

Note:

If you ar

e on a call and unplugged from the intercom, the headset will allow
you to complete your call, then it will turn off approximately three seconds
after the call is terminated. To use the headset when unplugged from the
intercom (to listen to secondary audio sources or to make or receive calls),
we recommend you disable the Auto Off feature for uninterrupted functional­ity. See “Auto Off” on page 12.

22 - English

Using the Headset

Reconnecting to a previously connected device

Each time you turn on the Bluetooth feature, the headset will attempt to reconnect
with the two most recently connected Bluetooth

1. Turn the headset on.

Make sur

2.

e the Bluetooth indicator is flashing blue. If not, press

The indicator flashes blue.

3. To confirm connection, check the Bluetooth device list on your device.

®

devices.

.

Recovering a lost connection

If a connected Bluetooth device moves out of range, the connection will be lost.
The headset will automatically attempt to reconnect.

If the headset is unable to reconnect, it will go back into pairing mode. After five
minutes of inactivity
range, and press

, the Bluetooth feature will turn off. Move the device back into

once to reconnect.

Disconnecting a Bluetooth device

• On the headset, press and hold for 5 seconds to turn the Bluetooth feature
off.

•

On your device, tur

•

Move the Secondary Audio Mode selector to the OFF position.

n the Bluetooth feature off.

Clearing the headset pairing list

With the Bluetooth feature on (Bluetooth indicator flashing), press and
hold
pairing mode.

and at the same time for seven seconds. The headset will return to

Controlling Bluetooth volume

Use the Bluetooth volume controls on the right side of the control module to
control the volume of a connected Bluetooth device.

Volume
up

Volume
down

• Each press increases or decreases the volume by one level.

• Press and hold the volume button to change the volume continuously.

In-call muting

Press and at the same time. Repeat to unmute.

Note: The microphone will mute for calls only, not for the intercom.

English - 23

Using the Headset

Secondary audio modes

If you have connected one or more secondary audio sources to the headset, you
must decide how you want to hear those secondary sources.

T

o select how you will hear your secondary audio sources, use the Secondary

Audio Mode selector on the control module.

Secondary Audio Mode selector

The selector has three positions: MUTE, MIX and OFF.

Position Function Description

MUTE

Intercom prioritized
over any secondary
audio sources

If an intercom signal is detected, all
secondary audio sources are temporarily
muted. Secondary audio will return after
intercom audio ceases.

Also see “Managing multiple secondary
sources” on page 25.

MIX

OFF

Intercom mixed with
any secondary audio
sources

Intercom only

Note: In OFF mode,

Bluetooth

power is
disconnected,
and all
antennae are
disabled.

All secondary audio sources are mixed with
the intercom audio. (Audio from a connect­ed device will keep playing during intercom
communications).

Note: In MIX mode, you will hear a

maximum of two audio sources – the
intercom plus one secondary source.

Also see “Managing multiple secondary
sources” on page 25.

Only intercom audio is active. All secondary
audio sources are off.

®

Note: If you switch to OFF mode while

connected to a Bluetooth source,
you many need to re-establish your
Bluetooth connection the next time
you turn on the headset.

Note: Only one secondary source can be heard at a time. Audio from a secondary

source will never override intercom communications.

Incoming and outgoing phone calls automatically mute all other

Note:

secondary
audio sources (when the Secondary Audio Mode selector is in either the
MUTE or MIX position). During a Bluetooth phone call, the intercom and the
phone call will be heard as mixed.

24 - English

Using the Headset

Managing multiple secondary sources

The headset can connect one AUX (wired) source and up to two Bluetooth®

wir

(

eless) sources at a time.

If you are likely to receive important information from a particular secondary source
(such as a GPS or a warning system), you can assign priority to that source. This
insures that incoming audio from the priority source will always override other
source.

Setting the Priority (BT-AUX) switch

To assign priority to one of your secondary sources:

1. Locate the Priority (BT-AUX) switch inside the battery compartment.

ON - OFF

AUTO ON

AUTO OFF

ON - OFF

2. Set the switch to the correct source (BT or AUX) as shown below.

Bluetooth source

AUX source

When the switch is in the BT
position, the Bluetooth source
will override the AUX source if
a signal is detected.

When the switch is in the AUX
position, the AUX source will
override the Bluetooth source if
a signal is detected.

Note: Incoming and outgoing phone calls will always override any other

secondary source.

English - 25

Headset Care and Maintenance

Instructions for continued airworthiness

Bose recommends following the general care and maintenance instructions in
this guide. With normal use, items such as windscreens and ear cushions require
periodic replacement. If cleaning or replacement of these items is needed, follow
the recommendations on the following pages. All other care and maintenance, in
and out of the warranty period, must be performed by Bose or an authorized repair
facility.

Caution:

Do not immerse the headset in water or any other liquid. If the headset
is immersed in liquid, do not use it. Contact Bose Technical Support for
assistance.

Cleaning the headset

General cleaning

Gently wipe the outside surfaces of the headband, connectors, plastic parts,
and headband cushion, using a soft cloth moistened with water and mild soap.
Take special care when cleaning the ear cushions and the outside surfaces of the
earcups. Do not immerse ear cushions in water or any other liquid.

Headset earcup openings

The TriPort® headset opening and the microphone opening must remain clean and
free of debris. Check to ensure that the openings on each earcup are clean before
each flight.

Triport headset opening

Microphone opening

When wiping down the headset earcups, be sure not to force any dirt or debris into
the openings. Carefully use tweezers, if necessary, to remove foreign matter that
may be lodged in the openings. Do not blow air into or vacuum the openings as
this may damage the headset.

26 - English

Headset Care and Maintenance

Microphone windscreen

Remove the windscreen from the microphone as described in “Microphone
windscr

Rinse and air dry the windscreen. Make sure the windscreen is completely dry, then
reattach.

een replacement” below.

Earcup inner screen

Do not attempt to remove, replace, repair, or clean this component. Located inside
the earcup, the inner screen is critical to proper headset operation. If the screen
appears to be damaged or worn out, contact Bose.

If the inner screen becomes damp from environmental moisture such as light rain,
dew, perspiration, or condensation, allow it to air dry only. Do not use electric
heaters, blowers, or hair dryers to dry the inner screen.

Headband cushion

1. Remove the cushion as described in “Headband cushion replacement” on
page 29.

2.

Place the cushion in a solution of water and a mild deter

3. Allow the cushion to air dry, then reattach.

gent.

Replacing parts

Through normal use, parts like windscreens and ear cushions may require periodic
replacement. Replacement parts can be ordered directly from Bose Corporation.
Please refer to “Contact information” on page 41.

Microphone windscreen replacement

1. Gently slide or roll the windscreen off the microphone.

2. Slide the replacement windscreen on and make sure it fits completely over the

microphone.

English - 27

Headset Care and Maintenance

Ear cushion replacement

As a general rule, ear cushions should be replaced every six months or every 350
hours of use, depending on how often you fly. You may have to replace them more
often, if you:

Have a full bear

•
Subject the headsets to sever

•
airplane outside in severe cold or heat.

Put excess strain on the cushions because of impr

•

Indications that the ear cushions need replacing include:

Flaking of the outer covering.

•
Cuts or tears.

•
Flattening of the cushion, r

•

To extend the life of the ear cushions, perform regular cleaning as described in
“General cleaning” on page 26.

To replace the ear cushions:

Grasp the ear cushion skirt wher

1.

Gently pull the ear cushion skirt up and away fr

2.

d or heavy whiskers.

e temperature extremes such as parking your

oper storage.

educing the effectiveness of the seal.

e it folds into the slot on the earcup.

om the earcup.

3. Properly align the replacement ear cushion with the earcup.

4. Tuck an edge of the ear cushion skirt into the slot behind the ear cushion

flange. Be careful not to fold the skirt over.

5. Gently stretch the cushion around the earcup, working the skirt into the slot as

you go.

6. Grasp the ear cushion and adjust its position to remove any folds in the skirt

and wrinkles in the cushion.

Battery replacement

Refer to “Inserting and replacing the batteries” on page 13.

28 - English

Headset Care and Maintenance

Headband cushion replacement

The headband cushion is designed to give the maximum level of comfort to your
headset.

Bose recommends that you replace the cushion after regular care and maintenance
fails to restore the wool pile to its original size and shape.

To replace the cushion:

On a pr

1.

2.

otected surface, turn the headset upside down. Remove the old

cushion from the headband.

While still holding the headband open, align the center of the ne
with the center of the headband and press firmly from the center toward the
outside.

w cushion

Microphone assembly or terminator cover replacement

Replace the microphone assembly or terminator cover as described in
“Attaching the microphone assembly” on page 10.

Storage

• Store the headset in a ventilated area away from direct sunlight.

•

Remove the batteries befor

e storing the headset for extended periods.

English - 29

Troubleshooting

Look for the problem in the left column of the table, then follow the “What to do”
instructions in the right column. If the problem persists, contact Bose using the
contact information on page 41 of this guide for assistance.

Warning:

Do not attempt to disassemble or service the inside of the ear

cups or
other parts of the headset. Only the boom microphone cable, access
cover, batteries, windscreen, headband cushion, and ear cushions are
replaceable by the user. For instructions on how to care for and maintain
the headset, see “Headset Care and Maintenance” on page 25.

Noise reduction

Problem What to do

Communication,
but no Acoustic
Noise Cancelling®
noise reduction
in either ear

• Make sure the headset is turned on.

• On the control module, check the power indicator. See page 18.

• If using aircraft power, check the aircraft fuse or circuit breaker.

•

If using battery power
correctly installed.

Warning:

Replace batteries with alkaline batteries only
any other battery chemistries.

, make sure the batteries are fresh and

. Do not use

No active
Acoustic Noise
Cancelling noise
reduction and no
communication

Make sur

•
connectors.

• Try using the headset in a different seat location.

• Remove the microphone assembly from the headset and check for
damage to the connector or pins. See “The microphone assembly”
on page 10.

Intercom communications

Problem What to do

Acoustic Noise
Cancelling noise
reduction, but no
incoming audio

• On the control module, make sure the volume controls are not set
too low. See “Intercom volume controls” on page 18.

•

On the inter
too low.

• Make sure the headset is firmly connected to the aircraft panel.

• Try a different seat location in the aircraft.

e the headphone plugs are securely inserted into the panel

com/radio, make sure the volume controls are not set

30 - English

Problem What to do

Low volume
of incoming
communications

Intermittent
communication

Reduced volume in
one ear only

No stereo separa­tion or communica­tions in one ear only

• On the control module, make sure the volume controls are not set
too low. See “Intercom volume controls” on page 18.

On the inter

•
too low.

• Inside the battery compartment, make sure the Intercom
(MON-ST) switch is correctly set for your intercom system.
See “The operation switches” on page 11-12.

Check that all headsets sharing the inter

•
(MON-ST) switch in the correct position.

Unplug all other headsets and see if the volume can be adjusted

•
to an acceptable level.

Make sur

•
T

ry the headset in a different seat location.

•

On the contr

•
too low. See “Intercom volume controls” on page 18.

Inside the battery compartment, make sur

•
(MON-ST) switch is corr
See “The operation switches” on page 11-12.

If your air

•
(MON-ST) switch is set to MON. Refer to “The operation switch­es” on page 11-12.

Depending on how your audio jacks ar

•
only one channel of audio supplied to the headphone jack. If the
Inter

com (MON-ST) switch is set to ST and you only hear commu­nications on one side, set the switch to MON. This will play audio
on both sides. U174 and 5-pin XLR plugs are mono audio only.

Troubleshooting

com/radio, make sure the volume controls are not set

com have the Intercom

e the headset is firmly connected to the aircraft panel.

ol module, make sure the volume controls are not set

ectly set for your intercom system.

craft has a mono audio system, verify that the

e the Intercom

Inter

e wired, there may be

com

Audio

Problem What to do

Reduced Acoustic
Noise Cancelling®
noise reduction,
intermittent clicking
sounds, or commu­nication distortion in
a loud environment

• On the outside of each earcup, make sure the TriPort® headset
openings are not blocked. If dust or dirt is present, carefully
remove the debris using tweezers. Do not vacuum or blow out
debris.

• Make sure there are no air gaps around the ear cushion seals.
If ear cushions appear worn, they should be replaced. Refer to
“Ear cushion replacement” on page 28.

Warning: If the headset emits any loud noise and related loss of

communications while in the Acoustic Noise Cancelling
mode, turn off the power switch. The headset will con­tinue to provide communications in the passive noise
reducing mode.

English - 31

Troubleshooting

Problem What to do

Squealing or
whistling sound
when the headset
is turned on

Low rumbling
sound with the
headset turned
on in a quiet
environment

Crackling sound
audible with
headset turned on
in a loud environ­ment, or Acoustic
Noise Cancelling
noise reduction is
intermittent

®

• Make sure the headset orientation is correct. Use the Left (L) and
Right (R) markings above the earcups to orient the headset cor­rectly.

Inspect the seal between the ear cushion skirt and the ear

•
skirt should fit into the slot on the earcup with no gaps. Replace
any cushions that appear to be worn out.

• Adjust the earcup fit to create a better seal on your head. The
headset’s low-force design makes it sensitive to items that
interfere with the seal around your ear. Make sure your ears are
completely inside the ear cushions, and that a hat or eyeglasses
with thick temples do not interfere with the seal.

If the squealing or whistling sound persists, tur

•
switch and contact Bose for service as soon as possible.

Adjust the ear

•
low-force design of the headset makes it sensitive to items that
interfere with the seal around your ear. Make sure your ears are
completely inside the ear cushions, and that a hat or eyeglasses
with thick temples do not interfere with the seal.

Check ports at the outside surface of each ear

•
they are not blocked. If dust or dirt is present, carefully remove the
debris using tweezers. Do not blow out or vacuum debris.

Inspect the seal between the ear cushion skirt and the ear

•
The skirt should fit into the slot on the earcup with no gaps.
Replace any cushions that appear to be worn out.

• Make sure the headset orientation is correct. Use the Left (L) and
Right (R) markings above the earcups to orient the headset
correctly.

• Adjust the earcup fit. Refer to “Wearing and adjusting the headset”
on page 15.

• If your headset is battery-powered, check to see if the battery is
low (indicated by fast blinking red LED).

•

If your headset is air
powering the headset is no less than 10 VDC.

•

Inspect the seal between the ear cushion skirt and the ear
skirt should fit into the slot on the earcup with no gaps. Replace
any cushions that have surface tears, torn stitching joints, large
wrinkles, or have become dried and stiff.

cup fit to create a better seal on your head. The

craft powered, make sure the voltage

n off the power

cup to ensure that

cup. The

cup.

cup. The

Warning: If the headset emits any loud noise and related loss of communications

while in the Acoustic Noise Cancelling mode, turn off the power switch.
The headset will continue to provide communications in the passive
noise reducing mode.

32 - English

AUX audio source

Problem What to do

No audio from
AUX source

Audio in one ear
only from the
AUX source

• On the AUX source, turn the volume up.

Make sur

•

control module and the AUX source.

• On the control module, make sure the Secondary Audio Mode

selector is in the MUTE or MIX position.
If the Secondary Audio Mode selector is set to MUTE, all

•

secondary audio sour
signal is detected. Secondary audio will return after intercom audio
ceases.

If you ar

•

from the AUX source. AUX audio will resume after the phone call
ends.

T

•

ry another AUX source.

Make sur

•

control module and the AUX source.
On the headset, make sur

•

properly connected. Refer to “Attaching the microphone assembly”
on page 10.

Troubleshooting

e the 3.5 mm AUX audio cable is firmly connected to the

ces are temporarily muted when an intercom

e on an active Bluetooth phone call, you will not hear audio

e the 3.5 mm AUX audio cable is firmly connected to the

e the terminator cover is in place and

Cannot hear
intercom com­munications while
listening to audio
from AUX source

AUX source does
not mute with
incoming intercom
communications

Cannot be heard
on a phone call

Make sur

•

system.

Make sure the 3.5 mm AUX audio cable is firmly connected to the

•

control module and the AUX source.

Inside battery compartment, check the Priority (BT

•

See “The operation switches” on page 11pages 11-12.
If the Secondary Audio Mode selector is set to MIX, all secondary

•

audio sour
the AUX source, set the switch to MUTE or OFF.

The headset does not support micr

•

nected to a device via the AUX audio cable. Hold the device closer
to your mouth to use the device’s mic. Or, try connecting the
phone via a Bluetooth connection.

e the headset is firmly connected to the intercom/radio

-AUX) switch.

ces are heard as mixed with the intercom audio. To mute

ophone operation when con-

English - 33

Troubleshooting

Bluetooth® audio source

Problem What to do

No audio from the
Bluetooth source
to the headset
while on a call

Headset does not
pair with a device

Cannot
answer/end
a call

Headset does
not reconnect
to a previously
connected device

• On the control module, make sure the Secondary Audio Mode
selector is in the MUTE or MIX position.

On the contr

•
the Bluetooth indicator is flashing. If not, press

Make sur

•
feet from each other).

On the contr

•
up.

On the contr

•
the Bluetooth indicator is flashing purple. If not, press and hold

for one second.

• On the control module, make sure the Secondary Audio Mode
selector is in the MUTE or MIX position.

• Follow the instructions in “Pairing the first device” on page 20.

•

Delete
Try pairing again.

• Make sure your phone is properly paired and connected to the
headset. Refer to “Using the headset with a Bluetooth® device” on
page 20.

• Make sure the device is in range of the headset (30 feet or 10 m).

• On the control module, make sure the Bluetooth feature is on, and
the Bluetooth indicator is flashing blue. If not, press

On the contr

•
selector is in the MUTE or MIX position.

On your device, make sur

•
On your device, delete

•
Then try pairing again.

ol module, make sure the Bluetooth feature is on, and

e the phone and headset are in range (no more than 30

ol module, make sure the Bluetooth volume is turned

ol module, make sure the Bluetooth feature is on, and

BOSE A20 from your device’s Bluetooth device list. Then

ol module, make sure the Secondary Audio Mode

e the Bluetooth feature is on.

BOSE A20 from the Bluetooth device list.

once.

once.

Auto on

Problem What to do

Headset does
not turn on
automatically

• Inside the battery compartment, make sure the Auto On (ON-OFF)
switch is set to ON. See “The operation switches” on page
11-12.

• The Auto On feature only works with 5 pin XLR, 6-pin and 8-pin
connector versions of the cable. Check the aircraft specs to see if
the jack is getting power from the aircraft’s electrical system.

Auto off

Problem What to do

Headset does
not shut off
automatically

34 - English

• Inside the battery compartment, make sure the Auto Off (OFF-ON)
switch is set to ON. See “The operation switches” on page
11-12.

• It may take up to nine minutes for the headset to shut off when not
in use immediately after initial power up.

• Disconnect the headset from the aircraft. Then turn on the headset
and wait 15 minutes. If the headset does not turn off, contact
Bose Technical Support.

Installation

m

R

BLK/WH

Mounting the aircraft panel connector

The aircraft panel connector is part of the optional 6-pin wiring harness assembly.

Visit www.Bose.com or www.global.Bose.com for information or purchase.

Warning: The aircraft panel connector must be mounted by a technician who is

Mount the connector into a cutout, using the diagrams below as a guide.

qualified to perform this type of avionics installation for the aircraft you
are using.

12.5mm
.49"

Receptacle - Pinout (front view)

Pin 6

14.0m

.55"

Pin 1

Aircraft Interface Schematic

RED

BLK

WHT

BLU

WHT

WH/BLU

BLK/WH

1 V+IN

•

•

2 GND

3 COMM L

•

4 COMM

•

•

5MIC HI

•

6MIC LO

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 installation method.

English - 35

Technical Information

10-32

RED

(no connection to

Existing wiring to
aircraft intercom/

intercom/audio panel

Caution: Do not use excessive force or bend the installed connector. This may

damage or break internal solder joints.

The air

Note:

craft panel connector cannot be installed in an audio system using
transformer-coupled audio outputs. Contact Bose Technical Support, using
the contact information on page 39 for details.

Mono connection diagram

1V+IN
2 GND
3 COMM L

4 COMM R
5 MIC HI
6 MIC LO

Ring

(audio)

Barrel

(gnd)

Barrel

(audio gnd)

Existing PTT

switch

and wiring

Bose headset)

audio panel

V DC

1/2A

WHT/BLU

Microphone - Jack

TPP

(PTT)

Tip

(phone audio)

BLK

BLK/WH

WHT

BLU

WHT

BLK/WH

Headphone - Jack

Stereo connection diagram

10-32

V DC

1/2A

RED

BLK

WHT

BLU

WHT

WHT/BLU

BLK/WH

BLK/WH

1V+IN

2 GND

3 COMM L

4 COMM R

5 MIC HI

6 MIC LO

Existing wiring to

36 - English

aircraft stereo

Phone

audio (right)

Tip

(phone audio left)

Microphone - Jack

TPP

(PTT)

Stereo Headphone - Jack

Audio

Barrel

(gnd)

Barrel

(audio gnd)

Existing

PTT switch

and wiring

(no connection to

Bose headset)

Technical Information

WHT/BLU

Helicopter (U174) connection diagram

1/2A

prong jack

6 MIC LO
5 MIC HI
4 COMM R
3 COMM L
2 GND
1 V+IN

Barrel

(audio gnd)

WHT

BLU

WHT

BLK
RED

10-32
V DC

Existing single 4-

Existing wiring to

helicopter intercom/

audio panel

Note: Barrel ground (gnd) refers to aircraft grounds.

Details on making the connections

The pinouts for the optional installed connector are detailed in the table below:

Pin number Color Purpose

1 Red V+IN: Headset power (10-32 VDC). Use a 1/4 amp fuse or

2 Black GND: System ground. Connect to the existing audio

3 White COMM L: Phone communication: Left.

4 Blue COMM R: Phone communication: Right.

Note: For stereo operation, connect the left and right channels to their respective posi-

tions. For monaural operation, connect pins 3 and 4 together, and to the tip of the existing
phone jack.

5 White MIC HI: Microphone/Hi-audio. Connect to the portion of

6 White/Blue MIC LO: Microphone/Lo-ground. Connect to the portion

a 1/2 amp circuit breaker.

ground.

the existing microphone jack that corresponds to the ring
position of a headset microphone plug. Do not connect to
the tip (PTT) segment.

of the microphone jack that corresponds to the barrel
position of a headset microphone plug.

If the micr

Note:

ophone 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.

Comm Shield Black Shield from Comm L and Comm R wire pair.

Mic Shield Black Shield from Mic Hi and Mic Lo wire pair.

The wir

Note:

es connecting pins 3 and 4 and pins 5 and 6 are shielded, twisted pairs with
a black wire shield termination exiting each pair. If the existing wiring is not shielded,
connect the shields to the existing audio wiring shields, or connect the shield from
Comm L and Comm R wire pair to audio ground.

English - 37

Technical Information

Headphone Damage could occur to avionics equipment that is

Impedance Monaural mode: 160 Ohms ON and OF

Frequency response 15 Hz to 15 kHz

Microphone (Electret) Bias required: 8 to 16 VDC through 220 to 2200 Ohms.

Microphone (Dynamic) Impedance: 5 Ohm or 150 Ohm dynamic mic

Maximum ambient noise level 115 dBC SPL for full active noise reduction performance

Power source Battery-powered: Two (2) AA alkaline

Voltage Battery-powered: Two (2) AA alkaline batteries

Battery life Alkaline battery life: At least 45 hours in typical general

Current Operating: 25 mA in typical aircraft noise

Fuse/breaker recommended 1/4 amp, fast-blow fuse (AGC 1/4 amp fuse) or 1/2 amp

Headset weight 12 ounces

Headset size range Slider not extended:

Control module dimensions 1.5" (38.1mm) H x 1.5" (38.1mm) W x 4.92" (125mm) D

Temperature and Altitude
(Category A)

Bluetooth wireless technology 3.1

intended for use only with 600 Ohm headsets. If in doubt,
consult the avionics equipment manufacturer.

Stereo mode: 320 Ohms ON and OFF

Sensitivity: 92 dB SPL typical, measured at 1 mw,
1 kHz, full volume on a KEMAR ear simulator.

Sensitivity: Varies depending on bias and AC radio input
impedance. Typical output is 600 mV at 114 dB SPL. To
assure proper modulation of the radio, it is recommended
that an avionics technician adjusts its input to match the
output of the microphone.

Sensitivity: Equivalent to M-87/M-101

Aircraft-powered: 10 to 32 VDC

Aircraft-powered: 10 to 32 VDC

aviation aircraft noise. Duration varies with battery age,
ambient noise levels, temperature, ear cushion seal, and
use of the Bluetooth feature.

circuit breaker

8.425" (214mm) H x 6.34" (161mm) W x 3.15" (80mm) D

Slider extended:

10.2" (259mm) H x 6.6" (168mm) W x 3.15" (80mm) D

Operating: 5 to 131°F (-15 to 55°C)
Storage: -67 to 158°F (-55 to 70°C)
Altitude: 15,000 feet maximum pressure altitude for full
cancellation

38 - English

Technical Information

FAA Technical Standards Order

The Bose® A20® Aviation Headset that are approved to TSO and ETSO C139 are
appropriately marked. The product interface, cables, and microphones have been
designed to function in or withstand exposure to the following environmental
conditions:

Condition Category

Altitude and temperature A1

Salt fog S

AF conducted susceptibility B

Humidity B

Magnetic effect Z

Power input B

RF susceptibility T

Temperature and altitude A1

Vibration S, R, and U

Voltage spike A

Shock drop 12 times, 1 m onto concrete

Explosive atmosphere Passed

Environmental categories cited refer to RTCA/DO-160F and RTCA/DO-214
(March 2, 1993).

The conditions and tests required for TSO approval of this are minimum performance stan­dards. It is the responsibility of those installing this article either on or within a specific type or
class of aircraft to determine that the aircraft installation conditions are within the TSO stan­dards. TSO articles must have separate approval for installation in aircraft. The article may be
installed only if performed under 14 CFR part 43 or the applicable airworthiness requirements.

This device complies with FCC and Industry Canada RF radiation exposure limits for general
population. It must not be collocated or operating in conjunction with any other antenna or

transmitter.

English - 39

Service and Warranty Information

Locating the headset serial number

Your Bose® A20® Aviation Headset is identified by a unique headset serial number
located on the underside of the headband and underneath the headband cushion.
Reference this serial number when you register your product or contact Bose for
technical support.

Be sure to properly reseat the headband cushion by pressing down firmly. For more
information on replacing the headband cushion, see Refer to “Headband cushion
replacement” on page 29.

Headband cushion

Serial number

Warranty

Details of the limited warranty are provided on the warranty/product registration
card included in the product carton.

The warranty information provided with this product does not apply in Australia and
New Zealand. See www.Bose.com.au/warranty or www.Bose.co.nz/warranty for
details.

Limited warranty service

To return your headset to Bose for repair

Return your headset using the following procedures:

1. Contact the Bose organization in your country/region (visit
www.global.Bose.com for Bose contact information in your country/region) for
specific return and shipping instructions;

2. Label and ship the product, freight prepaid, to the address provided by the
Bose organization in your country; and

3. Place any necessary return authorization number prominently on the outside of
the carton. Cartons not bearing a return authorization number, where required,
will be refused.

40 - English

Service and Warranty Information

Contact information

Contact Bose for:

Spar

•

e parts and accessories

• Technical advice
Installation information

•

•

Warranty and repair information

In North America:

Bose Technical Support
145 Pennsylvania Avenue
Framingham, MA 01701-9168 USA
TEL: [phone] (US); 508-879-7330, ext. 62006 (outside U.S.)
FAX: [phone]
E-MAIL: [e-mail]

In Europe:

Bose Technical Support
Nijverheidstraat 8
1135 GE Edam
The Netherlands
TEL: +31 (0)299 - 390 111 (Main)
TEL: +31 (0)299 - 390 283 (Direct)
FAX: +31 (0)299 - 390 109

Online:

www.Bose.com
www.global.Bose.com
www.owners.Bose.com
www.facebook.com/BoseAviation
instagram.com/BoseAviation
twitter.com/BoseAviation

Ordering parts and accessories

The following accessories and customer-replaceable parts can be purchased
directly from Bose.

• Additional control module cable

- Specify: Bluetooth technology or conventional module

- Specify: Connector type

•

Ear cushion kit

Headband cushion kit

•

• Carrying case

Microphone windscreen

•

•

Clothing clip

Earcup access cover

•

•

6-pin connector to dual G/A plug cable adapter

6-pin connector to U174 plug cable adapter

•

• Service kit (includes ear cushion kit, microphone windscreen, and headband
cushion kit)

•

Aircraft panel connector installation kit

craft panel installation kit cover plate

•

Air

English - 41

©2015 Bose Corporation, The Mountain,
Framingham, MA 01701-9168 USA
AM746706 Rev. 00