At the end of the first quarter of 2023, Sony released three headphones at once, including the new form of Sony Float Run open-ear sports headphones, Sony WH-CH720N and Sony WH-CH520. Recently, I have made a detailed review of the Sony WH-CH720N, and this time I will look at the internal structure and configuration information through teardown.
SONY WH-CH720N adopts lightweight materials and exquisite design, which greatly improves the wearing comfort. In terms of functional configuration, it is equipped with a DSEE digital sound enhancement engine, which can restore part of the lost high-frequency sound and effectively improve the sound quality. Support 8 preset EQ, two-way ten-level adjustable equalizer. It also supports 360° on-site sound effects, bringing an immersive audio experience.
The noise cancellation performance has also been further improved. WH-CH720N is equipped with Sony V1 noise cancellation chip and supports 20-level ambient sound mode. Support AI smart noise cancellation, which can automatically detect activity status and location, and automatically switch preset ambient sound and noise cancellation schemes. It is equipped with beamforming technology and adopts a wind noise reduction structure to provide high-definition call effects. Support about 35 – 50 hours (ANC off/on) music playback. It also supports fast charging and wired connection mode.
We have previously teardown Sony products including: SONY INZONE H9, SONY WH-XB910N, SONY WH-1000XM4, SONY WH-1000XM3, PlayStation 5 PULSE, Sony LinkBuds S, SONY WF-1000XM4, SONY WF-XB700, SONY WF-H800, SONY WF-SP900, Sony Float Run, Sony LinkBuds, SONY XPERIA Ear Duo and SONY SRS-XB13 bluetooth speaker.
01/ SONY WH-CH720N Headphones Teardown
Remove the two earmuffs, and the inside of the earmuffs is designed with a dust-proof mesh protection.
The right headphone cavity cover is fixed by four screws. The inclined design is adopted, which is more in line with the structure of the human auricle, so that the sound can be received by the ear more effectively. There is a noise cancellation microphone in the middle of the sound outlet to pick up noise from inside the ear canal.
Take out the microphone. There are 5 pickup holes on the front of the feed-back noise cancellation microphone.
Remove the screws and remove the cover. The inside of the right headphone is equipped with a function button motherboard, a battery, and two pickup microphones.
Remove the screws and open the right headphone cavity.
Disconnect the wires and remove the speaker. The inner side of the cavity cover is provided with a red rubber ring for sealing and waterproofing.
There are tuning holes on the edge of the speaker to improve audio performance.
After actual measurement, the speaker size is about 30mm.
Remove the screws, and take out the function key board, battery and microphone unit inside the cavity. The wire goes through the suspension to the left headphone.
The circuit on one side of the function button main board is connected with the left headphone and microphone wires. Connect with the battery wire through the socket.
Socket for wires connected to the battery.
A total of 4 function buttons are equipped with the same specifications.
Feed-forward noise cancellation microphone for picking up external ambient noise.
The information on the label of the built-in lithium battery in the headphone, rechargeable lithium-ion battery pack, model: 722428, rated capacity: 520mAh 2.0Wh, nominal voltage: 3.85V, charging limit voltage: 4.4V, manufacturer: Chongqing VDL Electronics Co.,Ltd., made in China.
Peel off the outer label and insulating protective film – the silkscreen information on the cell is consistent with the outer label.
The circuit on one side of the battery protection board is equipped with a lithium battery protection IC, MOS tube and thermistor, which are responsible for the protection functions of the battery such as overcharge, overdischarge, overcurrent, and overheating.
The structure of the cover plate of the left headphone cavity is the same as that of the right headphone. A feed-back noise cancellation microphone is fixed in the middle.
Remove the screws and open the cavity of the left headphone.
The back cover structure of the left ear cavity is the same design as the right headphone.
The main board unit, the feed-forward noise cancellation microphone and the call pickup microphone are arranged inside the cavity.
The circuits of the two microphones are distinguished by wires of different colors. The black one is the feed-forward noise cancellation microphone, and the transparent one is the call pickup microphone.
The circuits on the motherboard side.
The circuit on the other side of the motherboard.
Power switch/bluetooth pairing button.
Two LED indicators for charging and bluetooth pairing status feedback.
3.5mm audio input interface.
MEDIATEK MT2822MA bluetooth audio SoC. It supports Bluetooth 5.2, integrates rich functions, and cooperates with Sony’s leading noise cancellation technology to provide consumers with an excellent listening experience. It has the characteristics of fast computing speed, good noise cancellation performance, and low power consumption. According to 52audio, Sony LinkBuds S, Sony WF-1000XM5, and Sony WF-1000XM4 all use the MT2822 solution.
The crystal oscillator that provides the clock for the bluetooth chip, the specification is 26.0MHz.
YONGFUKANG CS5801T overvoltage and overcurrent protection IC. Support front-end protection of lithium battery charger, the maximum input withstand voltage is 30V. The current limit is programmable with a maximum output current of 1.5A.
Silkscreen C 2BZ IC.
Screen printing 2S HE IC.
Two silkscreen 1553 2YF2 ICs.
SGMICRO SGM3157 SPDT CMOS Analog Switch. Operates from a single 1.8V to 5.5V supply and features low on-resistance, low voltage, and high bandwidth. For wired and wireless audio switching.
All components of SONY WH-CH720N over-ear noise cancellation headphones.
SONY WH-CH720N is the same as SONY WH-1000XM5 in terms of appearance, turning to a simple design style that is more in line with the current trend. At the same time, through the lightweight design, the weight of the body is controlled within 200g, with soft and skin-friendly head pads and earmuffs, it has a very comfortable and light wearing experience.
In terms of internal structure configuration, they are equipped with 30mm drive units and built-in two noise cancellation microphones. There is also a call pickup microphone inside the left headphone. The right headphone has a built-in battery unit with the capacity of 520mAh. The left headphone has a built-in motherboard unit, and the main control chip is MEDIATEK MT2822MA bluetooth audio SoC. Support Bluetooth 5.2, integrated Sony noise cancellation technology. Also adopted YONGFUKANG CS5801T overvoltage and overcurrent protection IC, and SGMICRO SGM3157 SPDT CMOS analog switch for wired/wireless audio switching.