Sennheiser HD 450SE Bluetooth 5.0 Wireless Headphone with Alexa - Active Noise Cancellation, 30-Hour Battery Life, USB-C Fast Charging, Foldable - Black (Open Sealed)

Sennheiser HD 450SE Bluetooth 5.0 Wireless Headphones – ANC, Alexa, 30-Hour Battery, USB-C – Black (Open Sealed)

Description

The Sennheiser HD 450SE is a closed-back, around-ear wireless headphone designed for music, movies, calls, commuting, and everyday listening.

It combines Active Noise Cancellation (ANC) with Bluetooth 5.0, high-quality wireless codecs including aptX, aptX Low Latency, AAC and SBC, a built-in dual-microphone beamforming system, and up to 30 hours of wireless playback with ANC activated.

The HD 450SE also features a dedicated Voice Assistant button for Amazon Alexa, Siri and Google Assistant, support for the Sennheiser Smart Control app, USB-C charging, optional wired listening, and a compact foldable design.

Brand: Sennheiser
Model: HD 450SE
Model Code: SEBT4
SKU: 509280
Type: Wireless Over-Ear Headphones
Connection: Bluetooth 5.0 / 3.5mm Wired
Active Noise Cancellation: Yes
Driver Size: 32mm
Battery Life: Up to 30 Hours with ANC
Charging: USB-C
Voice Assistant: Alexa / Siri / Google Assistant
Color: Black
Condition: Open Sealed

Key Features

• Active Noise Cancellation (ANC)
• Bluetooth 5.0
• Closed-Back Around-Ear Design
• 32mm Dynamic Drivers
• Up to 30 Hours Battery Life with ANC Active
• Approx. 2-Hour Charging Time
• USB-C Charging
• aptX
• aptX Low Latency
• AAC
• SBC
• Bluetooth Multipoint – Up to 2 Active Connections
• Amazon Alexa Support
• Siri Support
• Google Assistant Support
• Dedicated Voice Assistant Button
• Dual Omnidirectional MEMS Microphones
• 2-Mic Beamforming Array
• Built-In Microphone for Calls
• Sennheiser Smart Control App
• Adjustable Equalizer
• Podcast Mode
• Firmware Updates
• Foldable Design
• Optional 3.5mm Wired Listening
• Carry Case Included in Standard Retail Package
• Approx. 238g
• Black
• Open Sealed

Active Noise Cancellation

The HD 450SE features:

Active Noise Cancellation: Yes

ANC helps reduce surrounding environmental noise, making the headphones particularly useful for:

• Commuting
• Travel
• Office Use
• Studying
• Music Listening
• Movies
• Podcasts

The combination of ANC and the closed-back around-ear design helps provide a more isolated listening experience in noisy environments.

32mm Dynamic Drivers

The HD 450SE uses:

32mm Dynamic Drivers

with an official frequency response of:

18Hz–22,000Hz (-10dB)

Sennheiser specifies an SPL of 108dB at 1kHz / 0dBFS and total harmonic distortion of less than 0.3% at 1kHz / 100dB SPL.

Audio Specifications

• Driver Size: 32mm
• Driver Type: Dynamic
• Frequency Response: 18Hz–22kHz
• SPL: 108dB
• THD: <0.3%

Bluetooth 5.0

Wireless connectivity is provided through:

Bluetooth 5.0

Sennheiser specifies Bluetooth Class 1 and BLE compatibility.

Bluetooth Profiles

• A2DP
• AVRCP
• HFP
• HSP

Bluetooth Audio Codecs

• aptX
• aptX Low Latency
• AAC
• SBC

The inclusion of aptX Low Latency is particularly useful with a compatible transmitter/source when reduced audio-video delay is desired.

Bluetooth Multipoint

The HD 450SE supports:

2 Active Bluetooth Connections

This allows compatible users to maintain connections with two Bluetooth devices, such as a laptop and smartphone.

Up to 30 Hours Battery Life

Official battery life is rated at:

Up to 30 Hours

Importantly, Sennheiser specifies this figure for:

Bluetooth music playback with ANC activated.

Battery

Built-In Rechargeable Lithium-Polymer

Capacity

600mAh

Battery Life

Up to 30 Hours with ANC

Charging Time

Approx. 2 Hours

USB-C Charging

The HD 450SE uses:

USB-C Charging

Sennheiser specifies USB charging at:

5V / 500mA maximum.

Charging Port

USB-C

Fast Charging

Yes – marketed by Sennheiser as fast USB-C charging.

Amazon Alexa

A major feature of the HD 450SE special edition is convenient:

Amazon Alexa Integration

The dedicated Voice Assistant button can also provide access to:

• Amazon Alexa
• Siri
• Google Assistant

depending on the connected device and configuration.

Built-In Dual Microphone System

The HD 450SE includes built-in microphones for voice calls and voice-assistant interaction.

Official specifications identify:

Dual Omnidirectional MEMS Microphones

configured as a:

2-Microphone Beamforming Array.

Microphone Specifications

• Microphone Included: Yes
• Mic Type: Built-In
• Microphone Technology: MEMS
• Microphones: 2
• Pickup: Dual Omnidirectional
• Voice Processing: 2-Mic Beamforming
• Frequency Response: 80Hz–6kHz

Sennheiser Smart Control App

The HD 450SE supports the:

Sennheiser Smart Control App

providing features including:

• Equalizer Adjustment
• Sound Personalization
• Battery Status
• Firmware Updates
• Quick Guide
• Podcast Mode

Podcast Mode is designed to improve speech clarity for podcasts, audiobooks and other voice-focused content.

Foldable Design

The HD 450SE features a:

Compact Folding Design

making the headphones easier to store and transport.

The standard retail package also includes a carry case for travel and storage.

Optional Wired Listening

Although primarily designed as Bluetooth wireless headphones, the HD 450SE also supports:

Wired Audio

through the supplied audio cable.

Connection Modes

Wireless: Bluetooth 5.0
Wired: Yes – Audio Cable

This is useful when Bluetooth is unavailable or when users want a direct wired audio connection.

Closed-Back Around-Ear Design

The HD 450SE uses:

Around-Ear / Circumaural

earcups with a:

Closed-Back

acoustic design.

This combination provides passive isolation in addition to the headset's electronic Active Noise Cancellation.

Weight

Official Sennheiser specifications list:

Approx. 238g.

The relatively compact construction and folding design make the HD 450SE suitable for portable everyday use.

Specifications

Official Sennheiser technical documentation confirms the 32mm drivers, Bluetooth 5.0, codec support, dual-microphone system, 600mAh battery, 30-hour ANC playback, approximately two-hour charging time and 238g weight.

Quick Product Fields

• Noise Cancellation: Yes – Active Noise Cancellation (ANC)
• Noise Cancellation (Mic): Beamforming / Voice Noise Reduction
• Charging Port: USB-C
• Color: Black
• Microphone Included: Yes
• Mic Type: Built-In – Dual MEMS Beamforming
• RGB Lighting: No
• Compatible Devices: PC / Mac / Mobile / Bluetooth Devices
• Connection Type: Wireless + Wired

Additional Product Fields

• Bluetooth: 5.0
• Driver Size: 32mm
• Battery Life: Up to 30 Hours with ANC
• Charging Time: Approx. 2 Hours
• ANC: Yes
• Multipoint: Yes – 2 Active Devices
• aptX: Yes
• aptX Low Latency: Yes
• AAC: Yes
• Voice Assistant: Alexa / Siri / Google Assistant
• App Support: Sennheiser Smart Control
• Foldable: Yes
• Weight: Approx. 238g

Important HD 450SE vs HD 450BT Note

The:

HD 450SE

is a special edition based on the HD 450BT platform.

Sennheiser specifically introduced the HD 450SE with enhanced emphasis on convenient Amazon Alexa interaction, while retaining features such as ANC, Bluetooth 5.0, 30-hour battery life, aptX Low Latency and the compact folding design.

For this product, use:

Model: HD 450SE / SEBT4

Standard Package Contents

Sennheiser lists the standard package with:

• 1× Sennheiser HD 450SE Wireless Headphones
• 1× Audio Cable
• 1× USB-C Charging Cable
• 1× Carry Case
• Quick Guide
• Safety Guide

Because this unit is Open Sealed, physically verify the exact included accessories before sale.

Important Note – Open Sealed

This product is listed as Open Sealed, meaning the original packaging has been opened.

Before publishing or sale, verify:

• Headphone cosmetic condition
• Black finish
• Left / right audio channels
• Both 32mm drivers
• Bluetooth 5.0 pairing
• Bluetooth multipoint
• Active Noise Cancellation
• Built-in microphones
• Voice-call quality
• Voice Assistant button
• Alexa functionality
• Siri / Google Assistant functionality where supported
• Physical media controls
• Battery condition
• Battery charging
• USB-C charging port
• Wired audio connection
• Audio cable
• USB-C charging cable
• Folding hinges
• Ear cushion condition
• Headband adjustment
• Sennheiser Smart Control detection
• Carry case
• Packaging condition
• Documentation
• Warranty details

Best For

• Music Listening
• Travel
• Commuting
• Office Use
• Studying
• Movies & Streaming
• Podcasts
• Audiobooks
• Bluetooth Laptop Use
• Smartphone Listening
• Voice Calls
• Users Who Want ANC
• Users Who Want Long Battery Life
• Users Who Want aptX Low Latency
• Users Who Use Amazon Alexa

Why Choose the Sennheiser HD 450SE?

• Active Noise Cancellation helps reduce distracting environmental sound.
• Bluetooth 5.0 provides reliable wireless connectivity.
• Supports aptX, aptX Low Latency, AAC and SBC codecs.
• Provides up to 30 hours of battery life even with ANC activated.
• USB-C charging with approximately two-hour full charging time.
• Dedicated Voice Assistant control supports Alexa, Siri and Google Assistant.
• Dual beamforming microphones support calls and voice interaction.
• Bluetooth multipoint supports two active device connections.
• Sennheiser Smart Control provides EQ, Podcast Mode and firmware updates.
• Foldable design makes the headphones easier to carry and store.
• Optional wired listening provides additional connection flexibility.
• Lightweight 238g closed-back around-ear construction is suitable for everyday listening and travel.