Features:

Highest Level of Dual Hybrid Noise Cancelling. Multiple MEMS microphones

Graphene coated PEEK diaphragm speaker for smooth, clean, and elegant sound

Stable Connection in crowed areas

Excellent Quality Call Sound

Approximately 6.5 hours of playback, and up to 20 Hours of use with charger

Bluetooth® 5.0

Capacitive touch sensor control

What is in the box

Headphones / Charging Case

USB 'C' Cable

Headphone rubber tips for different sizes of ears

User's Manual

Charging case with headphones

Close up view of headphones

Side views of Headphone

Charger Interface

USB Interface

Speaker Sound Port

MEMS Microphones

Speaker Vent

Vent Port

Speaker Spatial Vent Port

View of Headphone with rubber ear piece removed

Vent Port

Since the Technics Headphone enclosure is glued together, the only way in was to cut into the headphone.

This is a destructive teardown

A Razsor knife was use to cut into the Technics headphone along the seam in the headphone. Then a Jimmy Tool was used to open up the headphone. Tweezers and a Pick Tool were used to removed the electronics from the enclosure

Once opened, we get our first look at the inside of the headphone

Double sided foam tape was used to hold the main the PCB to the Battery and to the Touch Sensor / Antenna PCB. This foam tape had to be cut free. Then Denatured Alcohol was used to remove the foam tape glue from the PCBs and Battery

Double Sided Foam Tape

Opening up the headphone, we can see the main PCB, Battery, Speaker, etc

Battery

Main PCB

Speaker

Speaker Sound Chamber

Touch Sensor and Antenna

At first, I wasn't sure about the solder balls. Then I realized they were used to anchor the USB and Power Interface pins on the outside of the Headphone to the internal circuit board.

I had to used a solder iron to remove the solder balls, so that the internal interface circuit board could be removed. I had to also remove solder from the speaker wires to free up the internal circuit board.

Internal Circuit Board that interface Power and USB to the Headphones

The internal circuit board was also attached a MEMS Microphone that appeared to be monitoring the Speaker Chamber of the Headphone, since it was faced in

I had to remove the outside panel with 'R' on it with a Razor Knife to free the MEMS Microphone. Once the MEMS Microphone was freed, the interface board circuit could be pulled out

USB and Power (Charger) Interface

Sound Ports

Internal Circuit Board that interface Power and USB to the Headphones

MEMS Microphone from plastic collar in the Headphone

MEMS Microphone separated from the Interface Circuit Board when removed from the side of the Speaker Chamber

There was not much to see on the internal interface board top side or bottom side. The was one IC component that could not be crossed. If you happen to know the component, please leave a comment below

Unknown Component

Full Sensor Flex/Charging PCB IC Identification:

Next the Speaker sound chamber cover was removed with the use of a Pick Tool and Tweezers. A Razor Knife was used to cut the glue holding the speak in place

The speaker had no identifiable markings

With Speaker removed, we can see the sound chamber and sound ports

Closeup view of the Battery

Li-Ion 3.7V, 0.32Wh

The battery appears to be from VDL Electronics Co., Shenzhen, China

Closeup view of the Antenna/Touch Sensor side of the Main PCB

DSP Group - C2A1A Hybrid Active Noise Cancellation (ANC) Codec and Audio Digital Signal Processor (DSP)

651DF1M9 - Could not cross part number, but during a web search found out that it may be an integrated battery management IC

W25Q32JWUUIMTR- SPI FLASH 32Mb

MEMS Microphone Port

Closeup view of some of the components on the Antenna/Touch Sensor side of the Main PCB

DSP Group - C2A1A Hybrid Active Noise Cancellation (ANC) Codec and Audio Digital Signal Processor (DSP)

Winbond-W25Q32JWUUIMTR SPI FLASH 32Mb

651DF1M9 - Could not cross part number, but during a web search found out that it may be an integrated battery management IC

Battery side close up view of the Main PCB

AIROHA AB1552 - ARM Cortex M4/Bluetooth 5.0 Dual Mode

913 MPS1 MEMS Microphone. The Headphone uses three MEMS microphones with this part number

Could not cross the part number. If you know the part, please leave a comment below. The 2D bar code on the part reads as STM9135G15JAS011

Crystal Oscillator

Unknown component. Labelled B2A. Please leave a comment if you happen to know this component

Unknown component. Labelled SV4CP 240. Please leave a comment if you happen to know this component. Separated from PCB during teardown

Closeup view of some of the components on the Battery side of the Main PCB

AIROHA AB1552 - ARM Cortex M4/Bluetooth 5.0 Dual Mode

913 MPS1 MEMS Microphone. The Headphone uses three MEMS microphones with this part number

Could not cross the part number. If you know the part, please leave a comment below. The 2D bar code on the part reads as STM9135G15JAS011

Unknown component. Labelled SV4CP 240. Please leave a comment if you happen to know this component. Separated from PCB during teardown

Closeup view of top and bottom side of the Touch Sensor Flex PCB and Antenna

Full Main PCB IC Identification:

Predicted Block Diagram of the Technics EAH-AZ70 (Japan) Bluetooth Headphones:

Teardown Exploded View of the Technics Headphone