Bose A20 Aviation Headset with Standard Dual Plug Cable User Manual

1. Introduction

The Bose A20 Aviation Headset is engineered to enhance the aviation experience by providing superior noise reduction and clear audio. This manual provides instructions for the setup, operation, and maintenance of your A20 headset with a standard dual plug cable.

Key features include:

• Advanced active noise reduction for a quieter environment.
• Comfortable fit with reduced clamping force for extended wear.
• Clear audio with active equalization for enhanced communication.
• Customizable audio prioritization control.

Figure 1.1: Bose A20 Aviation Headset with microphone extended. This image shows the overall design of the headset, highlighting the earcups, headband, and microphone boom.

2. What's in the Box

Verify that all components are present in the packaging:

• Bose A20 Aviation Headset
• In-line clothing clip
• Control module
• Two AA batteries
• Aux-in cable adapter
• Carrying case

Figure 2.1: Contents of the Bose A20 Aviation Headset package. This image displays the headset, control module, batteries, aux cable, and carrying case.

3. Setup

3.1 Battery Installation

The control module requires two AA batteries for operation. Ensure correct polarity when inserting the batteries.

1. Open the battery compartment on the control module.
2. Insert two AA batteries, observing the positive (+) and negative (-) markings.
3. Close the battery compartment securely.

3.2 Microphone Connection and Adjustment

The high-performance electret microphone can be connected to either the left or right ear cup.

1. Identify the microphone port on your preferred ear cup.
2. Insert the microphone boom firmly into the port.
3. Adjust the microphone position approximately 1/4 inch from your lips for optimal voice pickup.

Figure 3.1: Headset with microphone attached to the left earcup. This view shows the microphone boom extending from the earcup.

3.3 Connecting to Aircraft Intercom

The A20 headset features a standard dual plug cable for connection to aircraft intercom systems.

1. Locate the headset jacks in the aircraft cockpit.
2. Insert the larger plug (headphone) into the corresponding jack.
3. Insert the smaller plug (microphone) into the corresponding jack.
4. Ensure both plugs are firmly seated to prevent communication issues.

4. Operating Instructions

4.1 Powering On/Off

Press and hold the power button on the control module to turn the headset on or off. An indicator light will confirm the power status.

4.2 Active Noise Cancellation (ANC)

The A20 headset features active noise cancellation. This function is automatically engaged when the headset is powered on, significantly reducing ambient cockpit noise.

4.3 Audio Prioritization Control

The control module allows customization of audio prioritization. You can choose between "mute" and "mix" settings:

• Mute: An incoming communication signal will temporarily mute any auxiliary audio source.
• Mix: An incoming communication signal will be mixed with any auxiliary audio source, allowing both to be heard simultaneously.

Refer to the control module for specific buttons or switches to adjust this setting.

4.4 Auxiliary Audio Input

Connect external audio sources (e.g., music players, mobile devices) to the control module using the provided 3.5mm aux-in cable adapter. The headset supports audio sources with a 3.5mm audio jack.

4.5 Bluetooth Connectivity (if applicable)

If your A20 model includes Bluetooth, you can pair it with compatible devices. The headset supports Bluetooth version 3.1 with a range of up to 10 meters.

1. Activate Bluetooth pairing mode on the control module (refer to specific button on module).
2. Enable Bluetooth on your device and select "Bose A20" from the list of available devices.
3. Confirm pairing on your device.

5. Maintenance

5.1 Cleaning

• Wipe the headset surfaces with a soft, dry cloth.
• Do not use abrasive cleaners or solvents.
• Periodically inspect ear cushions and microphone windscreen for wear and replace if necessary.

5.2 Storage

When not in use, store the headset in its provided carrying case to protect it from dust and damage. Remove batteries if storing for extended periods to prevent leakage.

6. Troubleshooting

6.1 No Intercom Communications While Listening to Auxiliary Source

• Ensure the headset is firmly connected to the intercom or radio system.
• Verify that the 3.5mm aux audio cable is firmly connected to both the control module and the auxiliary source.
• Check the audio prioritization setting on the control module. If set to "mix," ensure the auxiliary volume is not overpowering the intercom. If set to "mute," ensure the intercom signal is strong enough to trigger the mute function.

6.2 Microphone Output Issues

Electret microphone sensitivity can vary. If experiencing issues with radio modulation, it is recommended that an avionics technician adjusts the radio's input to match the microphone's output. Typical output is 600 mV at 114 dB SPL.

Dynamic microphone impedance is 5 ohm or 150 ohm, with sensitivity equivalent to M-87/M-101.

7. Specifications

8. Warranty and Support

For warranty information and technical support, please refer to the official Bose website or contact Bose customer service directly. Keep your proof of purchase for warranty claims.

Bose Customer Service: www.bose.com/support