Sony WH-CH720N Teardown by 52Audio
The WH-CH720N is a solid headset, offering good noise cancellation, sound quality and if you can find it, a good price. Let us look at the teardown from 52Audio and see what is hiding underneath all that plastic. Photos courtesy of 52Audio.
First me must remove the ear cushions. Unlike the WH-1000XM5, the cushions on the cheaper WH-CH720N just slide off the plastic edge. This is like the previous model and the WH-CH520.
This is good and bad, on one hand, you will not break any plastic tabs on the cushions, but on the other hand, the material can rip if you are not careful when taking them off, or putting them back on.
I compared the ear pad material between the WH-1000XM5 and WH-CH720N, and the higher end WH-1000XM5 has much better material. the pads are smoother and feels more premium. The WH-1000XM5 ear pads also cut out noise better and form a tighter seal around the ears. This has a pretty big impact on noise cancellation performance.
With the cushion over off, we can see the 30mm driver. the feedback NC mic can be seen in the center of the driver. The WH-CH720N still uses regular copper wires for the connection. The WH-1000XM5 has moved to a ribbon cable.
If we compare the new model to the older WH-CH710N, there are some design differences.
The old model has the feedback NC cable exiting through the bottom where as the new model has the same wire from the side. The newer model also has the entire surface sunken down creating a deeper area and space for the ear. Finally the mesh surrounding the driver is also slightly thinner.
The WH-CH720N have no foam inside to cover the driver like the WH-1000XM5. This means only the mesh from the ear cushions will keep dust and dirt out, so in order to maintain the headset, it would be best to keep the mesh clean and dirt free.
Removing the NC mic, we can see it is an electret type microphone.
This is an unfortunate revelation. From the FCC filings, it almost looked like Sony used MEMS mics, but it seems they have gone the other route and went for electret. I am sure electret mics have some advantages over MEMS mics, but recall the issues WH-1000XM4 owners had with their feedback NC mics. The high pitched noise. This was due to moisture getting into the mic and damaging it. MEMS mics are a lot more resistant to moisture and should be less susceptible to this problem. And yes, the WH-1000XM4 uses electret mics for their NC mics, only the voice microphone array uses MEMS mics.
Will moisture be an issue for the WH-CH720N and the electret mic? Good question. Hopefully it will not be an issue but in high humid areas, any problems could arise faster.
