As an established and well-known audio company, BOSE has been developing for more than 50 years. The current product line has covered three categories of civil audio, professional audio and car audio, as well as aerospace technology, biomedicine and other fields. Its personal consumer electronics products also include smart audio glasses, smart speakers, over-ear headphones, true wireless earphones and sleep earbuds.
As the beginning of noise-canceling headphones, BOSE noise-canceling headphones have always been the benchmark in the industry. Recently, BOSE officially released a new generation of flagship head-mounted noise-canceling headphones, BOSE QuietComfort 45. The appearance continues the design of the BOSE QuietComfort 35 series, and the earmuffs are free of wrinkles. Functionally, it still focuses on active noise reduction. AWARE MODE has been added, equipped with four outward-facing microphones to achieve clearer calls, and it has a battery life of 24 hours.
52audio disassembled Bose audio products include: Bose QuietComfort Earbuds true wireless noise-cancelling earphones, Bose Sport Earbuds true wireless bluetooth earpones, Bose SOUNDSPORT FREE true wireless bluetooth headphones, Bose NC700 head-mounted active noise-cancelling bluetooth headset, Bose QuietComfort 35 II Head-mounted active noise reduction bluetooth headphone and Bose smart audio glasses, etc. Let’s take a look at the detailed dismantling report of this product.
| BOSE QuietComfort 45 headphones teardown
Into the disassembly part, first remove the left earmuff.
There are holes on the inside of the earmuffs to fix and increase air permeability. Blue memory foam can be seen inside the holes.
The speaker dust-proof mesh is attached to the cover of the sound cavity, and the L/Left logo is printed on the top.
The cavity label has the product name: QC45 bluetooth headset, model: 437310, input: 5V-0.5A, place of origin: Thailand, and various certification marks.
The inverted tube used for tuning in the cavity is fixed by a large amount of glue.
The inverted tube is made of metal material, and at the same time it communicates the air inside and outside, and plays a role in balancing the air pressure.
Open the dust-proof mesh, and there is a hard metal mesh underneath, which supports and reflects the sound to the noise-reducing microphone.
The wire under the metal mesh is connected to the noise reduction microphone.
Noise reduction microphone under the metal mesh.
The speaker in the sound cavity, the outer bracket is raised to support the metal mesh.
Remove the back cover of the headset. Two noise-reducing microphones are fixed on the inside of the cover and connected to the motherboard through a flat cable.
The message “868153-0010-L” is printed on the microphone cable.
Laser carving 214 UED2Q MEMS microphone.
The shell is made of PC+ABS material, printed with BOSE LOGO.
The internal structure of the headphone cavity.
Open the audio interface small board cable.
2.5mm audio interface female socket.
Open the main board of the left ear, no important components are set underneath.
The front circuit of the motherboard.
The inside of the headphone pressure relief hole is protected by a metal mesh.
The back cover of the speaker cavity.
The tuning hole of the tone cavity is used to maintain air circulation in the cavity.
The cover is fixed by a lot of glue.
The back structure of the speaker unit is designed with multiple tuning holes, and damping paper is attached around it to improve the acoustic performance.
Silkscreen information on T iron, GW, impedance: 32Ω, power: 20mW, production date: May 12, 2021.
After actual measurement, the speaker unit size is about 40mm.
The headset battery is fixed in a separate cavity.
Inside the battery cavity cover.
A cylindrical lithium-ion soft pack battery is used inside the headphone.
The label information on the battery, battery model: AHB110520CPS-02, rated voltage: 3.7V, charging limit voltage: 4.1V, rated capacity: 445mAh, from SYNergy ScienTech Corp., made in China.
The battery coding is consistent with the label information.
The battery is equipped with a circuit protection board, and the protection board is equipped with a PTC thermistor.
Remove the right earmuff.
Right headphone dust-proof mesh, printed R logo.
Right headphone inverted tube.
The structure under the dust-proof mesh of the right headphone is the same as that of the left headphone.
Lift the back cover of the right headphone.
There are also two noise-reducing microphones on the inside of the right headphone cover.
The internal structure of the right headphone cavity.
The cable connection point of the power input interface is reinforced with glue.
The front of the Type-C power input board.
Type-C power input on the back of the small board.
Silkscreen A5 IC.
LED indicator, black foam on the outside to prevent light leakage.
TI TPS25200 input overvoltage protection IC, silk screen SKB, is used to protect the internal equipment of the headset from damage, and the protection current can be set.
The main board of the right headphone and the small wire board extending from the left headphone are connected through a board-to-board connector.
The circuit on the motherboard side of the right headphone.
The circuit on the other side of the right headphone motherboard.
Onboard bluetooth antenna.
Power slide switch.
The main control chip adopts Qualcomm QCC5127 bluetooth audio SoC, Qualcomm QCC5100 series adopts digital active noise cancellation (ANC) technology integrated in SoC, quad-core processor architecture, built-in dual-core DSP audio subsystem, and supports the latest TWS+ technology. That is, the dual-channel synchronous transmission technology has lower wireless latency. What is more commendable is that it can reduce power consumption by up to 65% compared with previous transmissions in voice calls and music streaming.
According to 52audio, products from brands such as BOSE, SONY, 1MORE, Edifier, and vivo have all adopted Qualcomm solutions.
Silkscreen 116 10C IC.
Silkscreen 71215 BCBZ noise reduction IC, from ADI Analog Devices, customized by Bose.
The second ADI silk screen 71215 BCBZ noise reduction IC.
Two silk-screened ALU ICs.
External Q128J memory is used to store firmware information.
Silkscreen 1AS IC.
The IC of silk screen AL.
TI TLV627432 400mA output current synchronous step-down converter is used to supply power to chips such as the headset’s single-chip microcomputer.
ST STM32L4A6VG is an ultra-low power 80 Mhz Arm Cortex-M4 MCU with FPU, with 1 MB Flash memory, USB OTG, LCD, AES-256 and DFSDM for headphone function control.
Independent cavity cover of the right headphone.
Inside the cavity is the wire adapter plate that extends from the left headphone, and is not equipped with a second battery.
The transfer board is connected to the main board with a BTB connector.
All components of BOSE QuietComfort 45 head-mounted noise reduction headphone.
BOSE QuietComfort 45 head-mounted noise reduction headphone continue the design of the previous generation in appearance. The headphone shell is made of impact-resistant glass fiber nylon material with strong toughness, and the earmuffs and head cushions are made of advanced protein leather material, providing all-weather Comfortable to wear. In terms of appearance and functionality, a more sturdy and durable custom metal hinge structure is adopted, which supports rotation and folding functions, and enhances the comfort of personalized wearing and the convenience of carrying out.
In the internal structure configuration, a 40mm dynamic driver is used, and a unique inverted hole structure is designed to enhance the bass effect. The left and right headphones are equipped with 3 microphones for active noise reduction and voice call functions. The left headphone is equipped with a 3.5mm audio output and a battery unit, with a battery capacity of 445mAh, from SYNergy ScienTech Corp.,.
The BOSE QuietComfort 45 left headphone mainboard wire passes through the head beam and connects to the right headphone adapter board, and then connects to the mainboard through the BTB. On the motherboard, the main control chip uses Qualcomm QCC5127 bluetooth audio SoC, integrated digital active noise cancellation (ANC) technology, quad-core processor architecture, built-in dual-core DSP audio subsystem, and supports the latest TWS+ technology. Two ADI noise reduction ICs with silk screen 71215 are connected to improve the noise reduction performance. It uses ST STM32L4A6VG ultra-low power MCU with FPU, TI TPS25200 overvoltage protection IC and TI TLV627432 400mA synchronous step-down converter.