Sony INZONE H9 II (WH-G910N) FCC Teardown

The INZONE H9 internal photos from the FCC listing have become available. Let us see what Sony has changed, and what they kept the same. We know Sony borrowed the driver from the WH-1000XM6, but did they borrow anything else from their flagship model? The photos are not the best quality, buy they provide some insight into the new model. Check out the 52Audio's teardown of the INZONE H9 for comparison photos.

Starting off with removing the earpads. I am not sure how one removes the earpads. It could be like the WH-1000XM6, where you just take them off, or you might have to squeeze the edges near the tabs to pop them out.

The design of the earpads is similar to the WH-1000XM6, but there are differences like the layout of the tabs/pins, and the material of the earpads, which now use nylon instead of synthetic leather. The area around the driver has similar design to the WH-1000XM6.

While we cannot see the feedback microphone in the previous photo, the next photo does confirm that Sony has changed the mic to MEMS. The previous model used an electret feedback mic. Switching the mic to MEMS should help with any moisture issues, but not fully eliminate them as other components can still suffer from moisture damage.

The driver assembly is held on with 4 screws, they appear to be phillips.

Looking at the photo, it does appear that both the feedback mic and driver use a flat PCB as a connection to the main PCB. There are 6 corresponding pins on both sides which connect to the flat PCB connection seen on the underside of the driver assembly.

I do not recall seeing such a connection before on a Sony headset, so I believe this is a first for Sony. Unless someone else knows otherwise?

Looking at the left side first, we have the main PCB, along with 2 accessory PCBs, one for the volume control, and the second one with the 3.5mm/microphone/USB-C connections. All the connections use flex PCBs and a connector, a welcome change as the previous model used a lot of soldered connections, with only one flex PCB connection.

Sony INZONE H9 - source 52Audio

Unfortunately the connection for the cable from the right side uses a soldered connection, just like the previous INZONE H9. A puzzling decision by Sony, considering both the WH-1000XM5 and WH-1000XM6 switched to connectors for cable between the right and left earcups.

Here are all 3 of the PCBs from the left side. The little black rectangle connected to the main PCB is the 2.4Ghz wireless antenna. Here is a close up of the main board. I have number the major components. 

1. Airoha AB1577 SoC
2. 2.4Ghz antenna connection
3. Microphone on/off button connector (missing, see post below)
4. Connection for 3.5mm/microphone/USB-C PCB
5. Feedforward MEMS microphone
6. Connection for volume control PCB
7. Connection for driver and feedback NC microphone
8. Unknown chip (could be a AWINIC Audio IC)
9. Connections from right side 

Sony mounting the feedftoward NC microphone on the main PCB might be a first, at least I do not recall seeing it on any previous modern headset. But if it works, then why not. The INZONE H9 also used 2 wireless chips, but they were different companies, a Mediatek MT2811, and a NXP NxH3670. The H9 also had Sony's own Audio IC, the CXD3782. It is possible this unknown chip is the audio IC in the new model.

Close up of the missing on/off microphone connection.

Flipping the main PCB over, we have a few more components. 

1. Feedforward MEMS microphone cover
2. Airoha AB1571 Bluetooth SoC
3. Bluetooth Antenna

Close up of the Airoha AB1571 chip.

 

The Airoha AB1577 and AB1571 appear to be the same chip, according to Airoha's own website. I suspect the 77 version has 8MB of embedded flash, where as the 71 only has 4MB. It is one of Airoha's newest chips, not top end, more so mid level.

This is the first accessory PCB.

1. Microphone connection
2. 3.5mm connection
3. USB type-C port
4. NC/AMB button
5. Flex cable connector to main PCB 

There is a small LED between the 3.5mm connection and USB port. This is is the charging LED. I do not see any resetable fuse like in the previous model. There are almost no components on the reverse side, apart from a few transistors. 

Sony INZONE H9 resetable fuse - source 52Audio

The second accessory PCB has the volume control. There is not much on the PCB, apart from the volume control and the PCB flex connector.

The fact both PCBs can easily be removed and replaced is great for repairability. That is assuming Sony will provide these parts for repair. There are dates codes on both PCBs, 2447, which could correspond to the 47th week of 2024 or late November 2024.

Moving to the right side now. We do not have any good close up of the right side components in situ, so the photo below will have to do for now. The battery holder has been made lighter by the additional of many small holes. I am surprised Sony did not do this on the WH-1000XM6, although I doubt this shaved off much weight. 

Here is are all of the parts from the right side removed from the earcup. The photo again is not the best quality. The battery uses a connector, so it can be easily replaced. 

Here is a closer look at the PCB.

1. Feedforward MEMS microphone
2. Battery connection
3. Connection for driver and feedback NC microphone
4. Connections for cable going to left side
5. On/Off button
6.  Bluetooth button
7. GAME/CHAT button
8. Bluetooth status LED
9. Power indicator LED

The PCB has a date code, 2502, which is early January 2025. So the development process most likely started in 2024. Shame the connections to the left side are soldered, as this PCB. If anything on this PCB fails, then the connections will need to be desoldered before the board can be replaced. There is not much on the other side of the PCB.

Turning to the battery, it seems that only one supplier is being used for this model, Springpower.

The mode number l is 772030, it is a 3.85V 500mAh Li-ion battery. If this battery sounds familiar, that is because Sony use the same one in the WF-1000XM5 case. The INZONE H9's used the battery model number 702428, rated at 3.85V 520mAh, also from Springpower. 

The new INZONE H9 II does improve upon the previous INZONE H9. Sony has switched to MEMS microphones, removable microphone, more connectors, and easier repairability. But the cable connecting both sides is still soldered to the boards, we only have dual ANC mics, and no resetable fuse near the USB type-C port. There are improvements, and even with a smaller battery capacity the H9 II has almost identical runtime to the H9.