Sennheiser Sebt4 Headphones Instruction Manual

HD 450BT
Around-ear headphones
Model: SEBT4

Instruction manual
Use the search function, the navigation (left) or the following links:
Start
“Product overview”
“Getting started”
“Using the headphones”
“FAQ/If a problem occurs …”
“Specifications”

Sennheiser electronic GmbH & Co. KG
Am Labor 1
30900 Wedemark
Germany
www.sennheiser.com
Version: 05/20 A02

Important safety instructions

▷ Read this instruction manual carefully and completely before using the product.
▷ Always include this instruction manual when passing the product on to third parties.
▷ Do not use the product if it is obviously defective or makes loud, unusual (whistling or beeping) noise.
▷ Only use the product in environments where Bluetooth® wireless transmission is permitted.

Preventing damage to health and accidents
▷ Protect your hearing from high volume levels. Permanent hearing damage may occur when headphones are used at high volume levels for long periods of time. Sennheiser headphones sound exceptionally good at low and medium volume levels.
▷ The product generates stronger permanent magnetic fields that could cause interference with cardiac pacemakers, implanted defibrillators (ICDs), and other implants. Always maintain a distance of at least 3.94″/10 cm between the product component containing the magnet and the cardiac pacemaker, implanted defibrillator, or another implant.
▷ Keep the product, accessories, and packaging parts out of reach of children and pets to prevent accidents. Swallowing and choking hazard.
▷ Do not use the product in an environment that requires your special attention (e.g. in traffic or when performing skilled jobs).

Preventing damage to the product and malfunctions
▷ Always keep the product dry and do not expose it to extreme temperatures (hairdryer, heater, extended exposure to sunlight, etc.) to avoid corrosion or deformation. The normal operating temperature is from 0 to 40 °C/32 to 104 °F.
▷ To avoid loud, unusual (whistling or beeping) noise and to ensure proper noise cancellation, do not cover the microphone openings of the active noise cancellation circuitry located on the outside of the ear cups.
▷ Use only attachments/accessories/spare parts supplied or recommended by Sennheiser.
▷ Clean the product only with a soft, dry cloth.
▷ Use the product with care and store it in a clean, dust-free environment.
Safety instructions for the lithium polymer rechargeable battery

WARNING
If abused or misused, the rechargeable batteries may leak. In extreme cases, they may even present a risk of:

• heat generation,
• fire development,
• explosion,
• smoke or gas development.

Important safety instructions

	Only use rechargeable batteries and chargers recommended by Sennheiser.
	Only charge the product/rechargeable batteries at ambient temperatures between +10 °C to +40 °C/50 °F to 104 °F.
	Do not heat the product/rechargeable batteries above +70 °C/140 °F. Avoid exposure to sunlight and do not throw the product/rechargeable batteries into fire.
	When not using the product/rechargeable batteries for extended periods of time, charge them regularly  (about every three months).
	Switch rechargeable battery-powered products off after use.
	Dispose of defective products with built-in rechargeable batteries at special collection points or return them to your specialist dealer.

Notes on data collection and processing and on firmware updates
This product stores individual settings such as the volume and the Bluetooth addresses of paired devices. This data is required for the operation of the product and is not transferred to Sennheiser or companies commissioned by Sennheiser and is not processed.
Using the “Sennheiser Smart Control” app, you can update the firmware of the product for free via an Internet connection. If the device on which the app is installed is connected to the Internet, the following data is automatically transferred to and processed by Sennheiser servers in order to provide and transfer suitable firmware updates: MAC address, Bluetooth Low Energy UUID, Bluetooth name of the product, firmware version of the product and version of the app. The data will only be used as specified and will not be stored permanently.
If you do not want this data to be transferred and processed, do not connect to the Internet.

Intended use/Liability
These headphones have been designed as an accessory for Bluetooth-compliant devices. They are intended for wireless audio communication such as music playback and phone calls via Bluetooth wireless technology. It is considered improper use when the product is used for any application not named in the corresponding product documentation. Sennheiser does not accept liability for damage arising from misuse or improper use of this product and its attachments/accessories. Sennheiser is not liable for damages to USB devices that are not consistent with the USB specifications. Sennheiser is not liable for damages resulting from the loss of connection due to flat or overaged rechargeable batteries or exceeding the Bluetooth transmission range. Before putting it into operation,  please observe the respective country-specific regulations.

Package contents

HD 450BT around-ear headphones Model: SEBT4

USB cable with USB-C connector

Analog audio cable with 3.5 mm jack plug and 2.5 mm jack plug, length approx. 1.5 m

Carry case

Quick guide

Safety guide

Online you can find:
• this detailed instruction manual and additional information www.sennheiser.com/download
• the Sennheiser Smart Control app for configuring the headphones and for additional functions www.sennheiser.com/smartcontrol

A list of accessories can be found on the HD 450BT product page at www.sennheiser.com. Contact your local Sennheiser partner: www.sennheiser.com > “Service & Support”.

Product overview

1. Headband
2. Earcup joints
3. Ear cups, steplessly adjustable
4. On/off button for the headphones and the active noise cancellation ANC pressing for 4 seconds activates the Bluetooth pairing mode
   pressing 1x activates/deactivates ANC
5. LED
6. Input for analog audio cable; when a cable is connected, flight mode is activated/Bluetooth is deactivated
7. USB-C socket for charging
8. Volume – button (volume down)
9. Volume + button (volume up)
10. 3-way multi-function button for music and call functions
11. Voice assistant button
12. Earpads
13. Speech microphones (2 pcs.) for phone calls

Overview of the LED display
During operation

LED		Meaning; the headphones
3X	flashes blue 3x	switch on
	flashes blue	are switched on
3X	flashes blue 3x	are connected to a device via Bluetooth
	flashes red/blue	are in Bluetooth pairing mode
3X	flashes red 3x	are not connected to a device via Bluetooth or the  connection has been Lost
3X	flashes purple3x	ANC is activated/deactivated

During phone calls

LED		Meaning
	flashes blue	Incoming call
	flashes red	Incoming call and the rechargeable battery of the headphones is almost empty

If the LED does not light up immediately during charging, clean the charging contacts and charge the headphones until the LED lights up again (> 11).

Notes on voice prompt
The headphones output voice prompts for various functions (see examples below).

Notes on beeps/acoustic signals
The headphones output beeps/acoustic signals for the following functions.

Getting started

1. Charging the rechargeable battery
The headphones’ rechargeable battery is not fully charged upon delivery. Before using the headphones for the first time, charge the rechargeable battery for a complete charging cycle without interruption(>11).

2. Installing the Smart Control app on your smartphone
The Sennheiser Smart Control app allows you to use all functions and settings of the headphones and to e.g. adjust the sound to your liking using the equalizer (> 15).

http://www.sennheiser.com/smartcontrol

3. Connecting the headphones to a Bluetooth device
Connect the headphones to your smartphone via Bluetooth (> 12).

4. Putting the headphones on and adjusting the headband
For good sound quality and best possible wearing comfort, the headband can be adjusted to properly fit your head (>17).

Using the headphones

Information on the rechargeable battery and the charging process
The headphones have a built-in rechargeable battery. A complete charging cycle takes approx. 2 hours. Before using the headphones for the first time, charge the rechargeable battery for a complete charging cycle without interruption. When the headphones are being charged, the  LED lights up (> 7).
Once the headphones are fully charged, the LED flashes blue 5x and then goes off. When the battery charge drops to a critical level, a voice prompt asks you to recharge the headphones (“Recharge headset”).
Sennheiser recommends using the supplied USB cable and a compatible standard USB power supply for charging the headphones.
While the headphones are being charged, you can still listen to music or make phone calls. In this case, however, the charging time may be longer.
Charging the headphones’ rechargeable battery

1. Connect the USB-C connector of the charging cable to the USB socket of the headphones.
2. Connect the USB-A connector to a corresponding socket of a USB power source (*to be ordered separately). Make sure that the USB power source is connected to the power supply system. The charging process of the headphones begins. The LED displays the charge status:

LED		Meaning
	lights up red	Rechargeable battery is being charged
	flashes blue 5x then goes Off	Rechargeable battery is fully charged

If the LED does not light up immediately during charging, clean the charging contacts and charge the headphones until the LED lights up again (> 11).
You can speed up the charging process by charging the headphones when they are switched off.

Connecting the headphones to a Bluetooth device
To be able to use the Bluetooth wireless connection, you must register both devices (headphones and e.g. smartphone) once. This process is called pairing.
If operation differs from the steps mentioned, also refer to the instruction manual of the Bluetooth device you are using.

When you switch on the headphones for the first time, they automatically switch to pairing mode.

Information on the Bluetooth wireless connection
The headphones are compatible with Bluetooth 5.0.
If your audio source supports one of the following high-resolution audio encoding methods, music is automatically played in high audio quality: aptX, aptX LL or AAC. Otherwise, the headphones will play your music in normal audio quality (SBC).
Paired devices establish the Bluetooth wireless connection immediately after switch-on and are ready for use.On switch-on, the headphones automatically try to connect to the last connected Bluetooth device.The headphones can save the connection profiles of up to eight Bluetooth devices with which they have been paired. If you pair the headphones with the ninth Bluetooth device, the saved connection profile of the least used Bluetooth device will be overwritten. If you want to re-establish a connection with the overwritten Bluetooth device, you have to pair the headphones again.

Paired and connected Bluetooth device
Paired Bluetooth device (currently not connected)

Pairing the headphones with a Bluetooth device
1. Switch the headphones off and place them close to the Bluetooth device (max. 20 cm).
2. Press and hold the on/off button for 4 seconds. The LED flashes red and blue. The headphones are in pairing mode.
3. Activate Bluetooth on your Bluetooth device.
4. Via the menu of your Bluetooth device, start the search for new Bluetooth devices.
All active Bluetooth devices in the proximity of your Bluetooth device are displayed.
5. From the list of found Bluetooth devices, select “HD 450BT”. If necessary, enter the default pin code “0000”.
6. If pairing was successful, you hear the voice prompt “Device (1) connected”. The LED flashes blue 3x.

If no connection is established within 5 minutes, pairing mode is terminated and the headphones switch to standby mode. If necessary, repeat the steps described above.
If you switch on the headphones for the first time (the pairing list is empty), they automatically switch to pairing mode.

Disconnecting the headphones from a Bluetooth device
▷ Via the menu of your Bluetooth device, disconnect the connection to the headphones.
The headphones are disconnected from the Bluetooth device.
You hear the voice prompt “Lost connection”. The headphones switch to standby mode.
To delete the Bluetooth pairing list of the headphones, > 29.

Installing the Smart Control app
To make full use of all the settings and functions of the headphones, you need to have the free Sennheiser Smart Control app installed on your smartphone.
Download the app from the App Store or Google Play and install it on your smartphone. Alternatively, you can use your smartphone to scan the following QR code or to call up the following Internet site: www.sennheiser.com/smartcontrol

http://www.sennheiser.com/smartcontrol

▷ Connect your smartphone to the headphones via Bluetooth (> 12).
▷ Start the Smart Control app.
▷ Follow the instructions in the app.
The Smart Control app recognizes the headphones and activates all available settings and functions.

Switching the headphones on
WARNING
The danger of hearing damage due to high volume levels! Listening at high volume levels can lead to permanent hearing defects.
▷ Before putting the headphones on, adjust the volume to a low level (> 19).
▷ Do not continuously expose yourself to high volume levels.

1. Unfold both ear cups. The joints click into place.
2. Press and hold the on/off button for 4 seconds.
The LED flashes red/blue. If Bluetooth is activated on the headphones, you hear the voice prompts “Power on” and “Device(1) connected”.  If Bluetooth is deactivated on the headphones, you hear the voice prompt “Power on”. If necessary, connect the audio cable to the headphones.

Make sure that Bluetooth is already activated on your Bluetooth device when switching on the headphones.
If Bluetooth is activated and the headphones cannot find a paired Bluetooth device within a few minutes, you hear the voice prompt “Lost connection”. The LED flashes red 3x. The headphones switch to standby mode.

Switching the headphones off
1. Press and hold the on/off button for 2 seconds.
2. You hear the voice prompt “Power off” and the LED flashes red 3x. The headphones switch off.

Putting the headphones on and adjusting the headband
For good sound quality and best possible wearing comfort, the headband can be adjusted to properly fit your head.
▷ Wear the headphones so that the headband runs over the top of your head. The markings R for the right side and L for the left side can be found on the inside of the headband.
▷ Move the ear cups up or down the headband slider until:
– your ears are comfortably covered by the ear pads,
– you feel even, gentle pressure around your ears,
– a snug fit of the headband on the head is ensured.
For optimal sound quality, the ear pads must completely surround your ears.

Retrieving information on the battery charge status
When the headphones are connected to your Bluetooth device, the battery charge status can be displayed on the screen of your smartphone (depending on the device and operating system used).
The Smart Control app also displays the battery charge status. You can retrieve information on the battery charge status on the headphones by pressing the center of the volume button 1x.

Adjusting the volume

WARNING
The danger of hearing damage due to high volume levels! Listening at high volume levels can lead to permanent hearing defects. Toggling between the audio sources may cause enormous volume jumps that can permanently damage your hearing.
▷ Before putting the headphones on and before toggling between audio sources, adjust the volume to a low level.
▷ Do not continuously expose yourself to high volume levels.

You can adjust the volume for music, voice prompts, beep sounds, and phone calls.
▷ If you are playing music or are on a call: Press the rear part or the front part of the volume button to increase or reduce the volume for music and phone calls.
When the maximum or minimum volume is reached, you hear a beep.

You can also adjust the volume using the connected Bluetooth device.

Information on active noise cancellation ANC
Due to its closed design, the headphones offer effective passive isolation from ambient noise.
In addition, the headphones have an active noise cancellation (ANC) function, which allows you to reduce ambient noise to a minimum. Even when ANC is activated, your headphones’ sound quality is always at its best.
You can activate or deactivate ANC when the headphones and your audio source are connected via Bluetooth, or the audio cable (provided that the battery is sufficiently charged).
If you want to create a quiet space in a noisy environment, you can simply use the headphones – without cable and disconnected from any Bluetooth device – as noise protection by using ANC (> 20).
Notes on active noise cancellation
• Continuous and uniform noise, such as motor or fan noise, is particularly well suppressed.
• Speech or high-frequency noise is significantly reduced but can remain perceptible.
• In very quiet environments, slight noise may occur. In this case, deactivate ANC.
• If unusual (whistling or beeping) noise occurs, take the headphones off and put them on again. Make sure that the ear cups properly fit around your ears.
To avoid loud, unusual (whistling or beeping) noise and to ensure proper noise cancellation, do not cover the microphone openings of the active noise cancellation circuitry located on the outside of the ear cups.

Activating/deactivating the active noise cancellation ANC
To activate the active noise cancellation ANC:
1. Switch the headphones on. Press and hold the on/off button for 2 seconds.
You hear the voice prompt “Power on”.
2. Press the on/off button 1x.
The LED flashes purple 3x.
ANC is activated.
To deactivate the active noise cancellation ANC:
▷ Press the on/off button 1x.
The LED flashes purple 3x.
ANC is deactivated.

Listening to music using the headphones
You can listen to music when the headphones and your audio source are connected via Bluetooth (> 12) or the audio cable (> 25).
Controlling music playback
The following music playback functions are only available when the headphones and the device are connected via Bluetooth. Some smartphones or music players may not support all functions.

Playing/pausing music
▷ Press the center of the 3-way multi-function button 1x.

3-way multi-function Button		Function
	Press 1x	Plays or pauses music

Playing the next track
▷ Slide the 3-way multi-function button backward.

3-way multi-function Button		Function
	Slide Backwards	Plays the next track in the playlist

Playing the previous track
▷ Slide the 3-way multi-function button forwards.

3-way multi-function Button		Function
	Slide Forwards	Plays the previous track in the playlist

Making phone calls using the headphones
The following call functions are only available when the headphones and smartphone are connected via Bluetooth. Some smartphones or communication apps may not support all functions.
Making a call
▷ Dial the desired number on your smartphone.
If your smartphone does not automatically transfer the call to the headphones, select “HD 450BT” as the output device on your smartphone (see the instruction manual of your smartphone if necessary).
Accepting/rejecting/ending a call
If your headphones are connected to a smartphone and you receive a call, you hear a ring tone in the headphones.
If you are playing music when you receive a call, the music pauses until you end the call.

3-way multi-function button		Function
	Press 1x	Accepts a call
	Press 1x	Ends a call Voice prompt “Call ended”
	Hold for 2 Sec	Rejects a call Voice prompt “Call rejected”
	Hold for 2 Sec	Continues the active call and rejects an incoming call
	Press 1x	Puts the active call on hold and accepts an incoming call
	Press 2x	Ends the active call and accepts an incoming call
	Press 2x	Toggles between active call and call on hold

Using the voice assistant/voice dialing
▷ Press the voice assistant button once.
The available voice assistant of your smartphone is activated (*depending on the system or app on your smartphone: Siri, Google Assistant,  or others. If no voice assistant is available, voice dialing may be activated).
▷ Ask the voice assistant your question or make a request.

To cancel the voice assistant/voice dialing:
▷ Press the voice assistant button 1x.

Adjusting sound effects/the equalizer
To be able to use the sound effects/equalizer, you require the Smart Control app (> 15).
▷ In the Smart Control app, select the desired sound effects. The sound effects are stored in the headphones. These sound settings are active even without using the Smart Control app, i.e. when you are using another Bluetooth device.

Using the audio cable/activating flight mode
If you connect the audio cable, flight mode is activated and the Bluetooth wireless connection is deactivated.
Use the audio cable when:
• wireless transmission is not allowed, e.g. during aircraft take-off and landing,
• the headphone’s rechargeable battery is empty,
• your audio source does not offer a Bluetooth connection.
The functions for controlling music and/or calls or voice assistance are not possible. The active noise cancellation ANC can be fully used provided that the rechargeable battery is charged.

Connecting the headphones using the audio cable
1. Insert the 2.5 mm jack plug of the audio cable straight into the headphones’ audio socket until you feel resistance.
2. Turn the 2.5 mm jack plug to the right until you feel resistance.
The jack plug is now locked in place and the audio cable is correctly connected to the headphones.
3. Insert the 3.5 mm jack plug of the audio cable into the audio output of your smartphone.
The Bluetooth wireless connection is deactivated.
Disconnecting the audio cable from headphones
1. Turn the 2.5 mm jack plug of the audio cable to the left until you feel a resistance.
2. Pull the 2.5 mm jack plug straight out of the headphones’ audio socket.
3. Pull the 3.5 mm jack plug of the audio cable straight out of the audio output of your smartphone.

Storing and transporting the headphones
Store the headphones in the carry case to prevent damage to the headphones when you are not using or transporting them.
▷ Fold up the headphones and place them in the carry case as shown in the illustration.

Care and maintenance

CAUTION
Liquids can damage the electronics of the product!
Liquids entering the housing of the product can cause a short-circuit and damage the electronics.
▷ Keep all liquids far away from the product.
▷ Do not use any solvents or cleansing agents.
▷ Clean the parts of the product only with a soft, dry cloth.

Replacing the ear pads

For reasons of hygiene, you should replace the ear pads from time to time. Spare ear pads are available from your Sennheiser partner.
1. Peel the earpad up and away from the ear cup.
2. Assign the right earpad to the right ear cup and the left earpad to the left ear cup.
3. Place the new earpad onto the ear cup. Make sure that the seam of the earpad points downwards.
4. Place the earpad around the ear cup so that the earpad is fixed in the notch of the ear cup.

Information on the built-in rechargeable battery
Sennheiser ensures and guarantees that the rechargeable battery performs at its optimum upon purchase of the product. If, upon purchase or within the warranty period, you suspect that the rechargeable battery is obviously defective or if a charging error/battery error is displayed (> 7), stop using the product, disconnect it from the power supply system and immediately return the product to any Sennheiser service partner.
Outside the warranty period, you can have the rechargeable battery replaced for a fee by your Sennheiser service partner. Contact your local  Sennheiser partner: www.sennheiser.com> “Service & Support”.

Installing firmware updates
Firmware updates can be downloaded free of charge from the Internet using the Sennheiser Smart Control app. Sennheiser recommends to always install the latest firmware version to ensure the best performance of your product.
▷ Connect the headphones to your smartphone and start the Smart Control app (> 15).
▷ The app provides information on available firmware updates and guides you through the installation process.

FAQ/If a problem occurs …

Current list of frequently asked questions (FAQ)
Visit the HD 450BT product page at www.sennheiser.com/download
There you will find a current list of frequently asked questions (FAQ) and suggested solutions.
Your question has not been answered or the problem persists?
If a problem occurs that is not listed in the FAQ section or if the problem cannot be solved with the proposed solutions, please contact your Sennheiser partner for assistance. To find a Sennheiser partner in your country, search at www.sennheiser.com > “Service & Support”.

Leaving the Bluetooth transmission range
Wireless calling and streaming are only possible in the Bluetooth transmission range of your smartphone. The transmission range largely depends on environmental conditions such as wall thickness, wall composition etc. With a free line of sight, the transmission range of most smartphones and Bluetooth devices is up to 10 meters. If you, and therefore the headphones, leave the Bluetooth transmission range of the smartphone, the sound quality deteriorates increasingly until you hear the voice prompt “Lost connection” and the connection breaks down completely. If you immediately re-enter the Bluetooth transmission range, the connection is automatically re-established.

Deleting the Bluetooth pairing list of the headphones
Make sure that Bluetooth is deactivated on the headphones.
1. Restart the headphones by switching them off and on again (> 17 and 16).
2. Simultaneously press and hold the on/off button and the 3-way multi-function button for 5 seconds.
The LED flashes purple. The headphones then stay in Bluetooth pairing mode.

When using the analog audio cable, the music only plays on one side of the headphones
The jack plug of the audio cable is not properly locked in place in the headphones’ audio socket:
1. Insert the 2.5 mm jack plug of the audio cable straight into the headphones’ audio socket until you feel resistance.
2. Turn the 2.5 mm jack plug to the right until you feel resistance.
The jack plug is now locked in place and the audio cable is correctly connected to the headphones.
3. Insert the 3.5 mm jack plug of the audio cable into the audio output of your smartphone.
The Bluetooth wireless connection is deactivated.

Specifications

Model: SEBT4

Manufacturer Declarations

Warranty
Sennheiser electronic GmbH & Co. KG gives a warranty of 24 months on this product.
For the current warranty conditions, please visit our website at www.sennheiser.com or contact your Sennheiser partner.
In compliance with the following requirements
• General Product Safety Directive (2001/95/EC)
• Compliant to Sound Pressure Limits according to country-specific requirements
EU declaration of conformity
• RoHS Directive (2011/65/EU)
Hereby, Sennheiser electronic GmbH & Co. KG declares that the radio equipment type SEBT4 is in compliance with the Radio Equipment Directive (2014/53/EU).
The full text of the EU declaration of conformity is available at the following Internet address: www.sennheiser.com/download.

Notes on disposal

• WEEE Directive (2012/19/EU)
• Battery Directive (2006/66/EC & 2013/56/EU)
The symbol of the crossed-out wheeled bin on the product, the battery/rechargeable battery (if applicable) and/or the packaging indicates that these products must not be disposed of with normal household waste, but must be disposed of separately at the end of their operational lifetime. For packaging disposal, please observe the legal regulations on waste segregation applicable in your country.
Further information on the recycling of these products can be obtained from your municipal administration, from the municipal collection points, or from your Sennheiser partner.
The separate collection of waste electrical and electronic equipment, batteries/rechargeable batteries (if applicable) and packagings is used to promote the reuse and recycling and to prevent negative effects caused by e.g. potentially hazardous substances contained in these products. Herewith you make an important contribution to the protection of the environment and public health.

Trademarks
Sennheiser is a registered trademark of Sennheiser electronic GmbH & Co. KG. Apple, the Apple logo, and Siri are trademarks of Apple Inc., registered in the U.S. and other countries. App Store isa service mark of Apple Inc. Android and Google play are registered trademarks of Google Inc. The Bluetooth® word mark and logos are registered trademarks owned by Bluetooth SIG, Inc. and any use of such marks by Sennheiser electronic GmbH & Co. KG is under license. Qualcomm aptX is a product of Qualcomm Technologies International, Ltd. Qualcomm is a trademark of Qualcomm Incorporated, registered in the United States and other countries, used with permission.

aptX is a trademark of Qualcomm Technologies International, Ltd., registered in the United States and other countries, used with permission.
Other product and company names mentioned in the user documentation may be the trademarks or registered trademarks of their respective holders.

References

• Sennheiser — Headphones, Microphones, Wireless Systems
• Sennheiser Product Downloads
• Smart Control App | Sennheiser