I was not expecting a teardown so quickly of the Sony WH-1000XM4, but 52Audio.com has delivered once again, so time to dive in, see what is new and compare it to the WH-1000XM3. Warning a lot of photos coming up.
I will not focus much on the exterior changes, so if anyone wishes to compare the exteriors, check out the links here (XM4, XM3). All photos can be viewed in larger size by clicking on them, and most comparison photos have the WH-1000XM4 on the left and the WH-1000XM3 on the right.
The first notable difference in the build is the inside plastic holding the driver and the sponge surrounding the driver. In the XM4, the plastic is one piece and the sponge does appear to be slightly bigger and fills out the space much more than the sponge in the XM3. This should help with passive noise cancellation.
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| Source: 52Audio.com - WH-1000XM4 sponge |
Looking at the XM3 for comparison. The sponge has less material than the XM4 sponge.
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| Source: 52Audio.com - WH-1000XM3 sponge |
Here we can see the interior plastic which holds the driver. In the XM4, it is made out of 1 piece, where as the XM3 has 2 pieces. Simplifying the design to 1 piece should help with rigidity, weight, and production. In addition, the design of the plastic is also quite different on the XM4 versus XM3. So while the XM4 and XM3 look almost identical on the outside, the interior is a different story it, as expected.
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| Source: 52Audio.com |
Next up is the feedback microphone located inside the headphones. The FB microphone is now covered by a plastic piece instead of just tape. The plastic cover affixes to the main unit with clips. I wonder why this design change has occurred, perhaps the tape was peeling off and the NC microphone was coming free?
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| Source: 52Audio.com |
Likewise the Feedback NC microphone has a different orientation on the XM4 than XM3. On the new XM4, the microphone is now perpendicular to the driver, where as on the XM3 it was parallel. I am not sure why this has been changed, perhaps this microphone is also involved for voice and noise cancellation during calls? Could this be the extra mic? Would love to hear Sony's reasoning for this change. If anyone has any ideas, please leave a comment below. Other than that, it looks like the microphone is the same.
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| Source: 52Audio.com |
Opening the right side reveals the battery and touch sensor. The touch sensor looks identical but upon closer inspection is a bit different. Around the touch sensor cover is a rubber seal, same a before. A small change, but significant, is the use of a ribbon cable which connects the small battery/touch sensor PCB to the main board. This helps with production since on the XM3, the wires were soldered to the board which takes more time than just plugging in a ribbon cable. As well, repair's should be quicker.
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| Source: 52Audio.com |
Another design change is the FeedForward NC microphone opening, now looking a lot better than on the XM3. This may not be something big, but it looks more premium and probably functions better.
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| Source: 52Audio.com |
A close up of the Feedforward NC microphone, showing a slightly different design.
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| Source: 52Audio.com |
Turning to the battery, it is identical in both models, the battery model is the LIS1662HNPC, rated at 1100mAh, 3.7V. While it would have been better if Sony used a slightly larger capacity battery, the fact it is not less is also a positive.
For those interested in seeing the changes on the battery/touch sensor PCB, check out the links at the end of the post, but one change is the charging IC is now the MPS MP2625B on the XM4, compared to the MPS MP2625 on the XM3. I believe they are identical apart from the Operating Input Voltage, which is lower on the XM4 (4V to 10V, versus 4V to 14V on XM3). This is not my field, so if anyone wishes to post any other differences, please leave a comment below.
One area different is the USB type-C PCB, it looks like there are less parts on it, but again not my field, just pointing out what I can see visually. Anyone know the reason(s) for the differences?
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| Source: 52Audio.com |
The NFC antenna on the inside on the left side is now smaller on the XM4. Reading a blog entry on NXP's site about antenna design, it seems that the smaller antenna would decrease the read range, but read range is also dependent on the chip inductor, which is identical on both models.
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| Source: 52Audio.com |
Focusing on the call microphones, sorry to break the bad news, but the microphone array has the same amount of mics, 3, no more, no less. The only difference I can see is that microphones are closer together on the XM4 than in the XM3. So perhaps the tighter arrangement has slightly improved the voice call quality from the various hands on videos I have seen. But the voice quality is still not stellar it seems.
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| Source: 52Audio.com |
So it seems that the amount of microphones has not changed, 5 on the left, 2 on the right. Perhaps Sony uses the NC mics now for the phone calls as well? But I have no idea if this is the case. It would have been great to see more microphones, perhaps 4 in the array or perhaps a similar array on the right side? Perhaps Sony does not really care to focus on call quality as much as sound quality and noise cancellation performance? This is my impression from the various interviewers I have read regarding the WH-1000XM3 an XM4.
Looking at the main PCB, there are some major changes, mostly for easier production/assembly/repair it seems, but also to newer components.
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| Source: 52Audio.com |
The QN1 can be seen in the middle of both PCBs, but the XM4 has it orientated differently. Next on the left we can see a ribbon cable connector on the XM4, where it was just soldered on cables in the XM3. I pointed this out in the FCC WH-1000XM4 teardown post. The soldered on wires on the bottom of the boards in both are for the microphones (NC) and drivers.
Close up of the Sony QN1, CXD90050.
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| Source: 52Audio.com |
The other side of the PCB has the Bluetooth SoC (Mediatek MT2811), Q128JWYIQ memory chip, LATTICE ice40ul1k low power FPGA and sensor manager, and the Cirrus Logic CS48L32. The XM3 has the CSR8675, Q64FWY memory chip, Cirrus Logic CS47L15, and STM32L071CZT6. The majority of the changes in the WH-1000XM4 have been under the skin rather than the external design.
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| Source: 52Audio.com |
Going back to the Cirrus Logic CS48L32 in the XM4, more can be found out here from Cirrus' website, the chip performs some the following functions:
- 24-bit audio processor with 104 dB signal-to-noise ratio
- supports up to four analog or four digital microphone (DMIC) inputs
- “always on voice” (i.e., voice trigger)
I am sure it has more functions, again not my field of knowledge, so check out the link above from Cirrus to see the other features/functions.
Finally, let us look at the proximity sensor. The major new addition to the XM4.
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| Source: 52Audio.com |
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| Source: 52Audio.com |
If anyone finds anything of interest in the teardown on 52Audio, please post it in the comments. The links to both WH-1000XM4 and WH-1000XM3 teardowns are posted below.
https://www.amazon.com/Shure-Cancelling-Headphones-Studio-Quality-Technology/dp/B084S1CYKF
ReplyDeleteSony should be inspired by premium materials and support for all codecs, aptx low latency, aptx hd !!!!
They are not using Qualcomm hardware anymore, so this is why they're not using any kind of aptX codec. The aptX Low Latency codec would be nice, though you also need to buy a transmitter for it. I didn't see too many devices having aptX LL transmission.
DeleteHey just wanted to say I am SO happy you are blogging about Walkman. Please keep updating! Hardware analysis is a huge attraction for me. Thank you!
ReplyDeleteMuch appreciated, I just wish I could post some walkman teardowns as well but not many of those around.
DeleteBest tear down ever. Could you please please post comparison between xm4 and xm3 headphones input jack and pcb with pictures if possible please. Thanks
ReplyDeleteI was wondering of you could replace the pcb (motherboard) of the MX3 by one of the XM4 and so update your XM3
ReplyDeleteNot sure, have not looked that closely at it to see if it would fit, but I feel it would not. Would have to first get your hands on a XM4 board.
DeleteHi, I was wondering if you can give me the domensions for the XM4's ear cups and ear pads (inner and outer). Im planning on comparing them to the xm3 and bose qc 35 ii, since ive heard that the xm3's were uncomfortable and the xm4's have been rumored to be very uncomfortable.
ReplyDeletesorry I do not have these dimensions.
DeleteInteresting tear down! I was looking into whether one could swap in a qi coil, perhaps by swapping out the battery. I'm curious if the qi charging would work, however, through the touch panel.
ReplyDeleteWould qi charging not require additional components on the PCB? Or could you just add a Qi receiver inside the headphones and then connect it inside to the usb type C port?
DeleteGreat write-up! Is there a way to block some holes so that the mic would be permanently disabled? I disable in the app and then it turns itself on. I have the latest software. It drives me nuts! or can I disassemble and remove some parts?
ReplyDeleteAny suggestions would be greatly appreciated.
which mic?
DeleteIs this the NC mic that sits in front of the speaker that causes the white noise moisture issue. You note the 4 has a redesigned holder sitting the mic on its side but its the same mic used. Im curious as to what causes the hiss, white noise, crackling issue so common in the xm3
ReplyDeletecould be, the mic is an electret type mic, not mems as in other brands. Not sure if the mk4 has the same issue you mention, but if it does, then it might be mic type used or just how sony has engineered it which is causing this issue.
DeleteBattery replacement seems very similar to the xm3...if not easier. Thanks for this!
ReplyDeletemaybe I will add the photos of the battery to the post to make it more clearer.
DeleteGreat Teardown .. Thanks!!
ReplyDeleteGreat Teardown!
ReplyDeleteOne question, sony headphones have this pressure optimisation feature in the app, how does that work? Doesnt look to me like there is any pressure sensor in there?
Hi. You show the feedback mic that sits on top of the speaker. Im looking for some details about the mic itself. Like what type of mic is this? Is it a condenser style mic or any kind of details would be helpful if you know. I want to find a replacement if at all possible. Thanks
ReplyDeleteEver find the rights mics? Been searching for years myself. Size is fairly obvious, sensitivity rating and to a degree frequency range are a hold up.
DeleteThere is just zero reliable information out there about a good replacement. Worthless Sony won't offer any information and their flawed design leaves many with expensive broken pieces of junk due to a component costing pennies.
Anyone out there with reliable information? Chances of this being seen? Very low. Oh well.
Can you replace the feedback bc and the battery or touch sensor or if they get damaged will I need to retire the whole headphone set?
ReplyDeleteYou should be able to replace all parts without any issues. they are not paired to the headset.
Delete