Sony’s flagship TWS IEMs offer an expansive feature set and engaging sound while improving upon their predecessors in every area.
- Good build, unique design
- Very comfortable to wear for longer periods
- Great microphone performance
- Good battery life
- Sony Headphones app offer many customization options
- ANC works well to filter out low frequency noises
- Smooth, analogue-ish tuning that’s never fatiguing
- Above average technicalities given the TWS landscape
- Somewhat bulky, smudge-prone shells
- Not the most technically proficient TWS IEMs out there
- At times buggy wear detection
- ANC can’t filter out high frequency noises
- Expensive
Where To Buy
Introduction
Sony’s WH series of headphones have become immensely popular in the Bluetooth headphones space. So it’s natural that Sony would also want to replicate that success in the TWS market.
Meet the Sony WF-1000XM4, the fourth generation of Sony’s flagship TWS Bluetooth IEMs. They promise class-leading ANC and exceptional tuning from the 6mm single dynamic drivers. The price reflects the positioning, as WF-1000XM4 are the most expensive TWS in Sony’s lineup.
Do the WF-1000XM4 warrant the high price and praise, or is it all for naught?
Case ⓘ
Battery ⓘ
- Battery Life: 12
- Connector: USB Type-C
- Wireless Charging: Yes
- Battery Capacity: Not specified
UX ⓘ
- Can be open easily with one hand: Yes
- Pass the shake test: Yes
- Light Indicators: Shows estimated battery life left and shows charging indicator
The case can be opened using one hand, and the top cover can lock itself when pushed backward, making it easier to take out the IEMs. The LED bar on the front shows the battery level and doubles as a charging indicator.
Design ⓘ
- Shape of the case: Rectangular
- Material: Soft-touch plastic
- Build Quality: Premium
The smaller carry case is a massive upgrade over the… massive WF-1000XM3 carry case. I am not a big fan of the soft-touch finish as it tends to attract smudges over time and looks dirty. However, ergonomically, it’s good.
Portability ⓘ
- Weight: 41g (case only), 56.7g (with earbuds)
- Volume: 4 cm x 6.7 cm x 3 cm = 80.4 cm cu
- Portability: Good
Earbuds ⓘ
Battery ⓘ
- Battery Life: 12 hrs (without ANC), 8 hours (with ANC)
- Charge Time (15mins): 120 mins playback time
The case holds an additional 16 hours of charge, coupled with the 8 hours (ANC on) or 12 hours (ANC off) of battery life on the IEMs themselves. I need to charge them about once a week during regular use (using the LDAC codec). Your mileage may vary.
Sony specifies that the WF-1000XM4 need 3 hours to be fully charged, but I’ve found that you can cut that time down to 1.5 hours using a USB-PD certified charger.
Many users have been reporting battery life issues on the WF-1000XM4. Sony has released the 2.0 firmware to address these issues alongside multipoint support. Sony recommends updating to this firmware for the best experience.
UX ⓘ
- Control Mechanism: Touch
- Touch Accuracy: Good
- Control Symmetry on both earbuds: No, individual setup for each earbud
- Mono Use: Yes, both sides
The circular faceplate acts as a touch-sensitive panel to control various aspects of the IEMs. Touch accuracy is good, with accidental activations mostly kept in check.
Still, I much prefer a button-based system over this type of touch control, where accidental touches are commonplace.
Design ⓘ
- Profile: High
- Material: Soft-touch plastic
- Comfort: Good
- Fit: Outstanding
The WF-1000XM4 look unlike any other TWS IEMs in the market. They have a distinct design that is accentuated by the golden vent on top. The IEMs have a large shell but are surprisingly comfortable to wear, thanks to the flattened inner faceplate and the thin but extended nozzle.
On the inner side of the IEM, there is the IR sensor for wear detection and the interfaces for charging alongside another vent. Beside the Sony logo is a mic outlined with a golden accent. The entire top surface has capacitive touch sensors that can be assigned various features and controls.
Mic ⓘ
- Noise Cancellation: Good
- Voice Pick-up: Good
The mic has good voice pickup, even in crowded places. Wind noise is not canceled as efficiently, but that’s a challenge for any microphone out there. I find the noise cancelation algorithm somewhat aggressive, resulting in some compression of sound.
Mic Demo
Sound ⓘ
- Driver: 6mm single dynamic driver
- Sound Signature: Warm, can be tuned via the app
- Bass: Good
- Mids: Outstanding
- Treble: Good
- Sound Detail: Good
Sony WF-1000XM4 have a warm, laid-back tuning in stock configuration.
Before going further with the sound impressions, I’d like to note that the WF-1000XM4 are quite sensitive to ear tip changes. The stock tips were too bassy and killed the treble sparkle further, reducing overall dynamics.
Bass response is mostly sub-bass focused. The bass emphasis in the stock setup somewhat clouds the lower-midrange.
Transients are softened slightly as a result, with the leading edge of acoustic and electric guitars sounding a tad smoothed out. It’s a pleasant coloration, though, since it adds to the overall “relaxed” nature of the IEMs.
There is zero shoutiness in the mids, and vocals sound tonally correct. Male vocals have added heft to them, and female vocals are pulled back into the mix and do not stand out too much. Treble is slightly darkened, slowly rolling off past 10kHz. Not a lot of air here.
The driver is faster than your average TWS but less snappy than some competitors. Staging is fairly well-rounded, wide enough to not feel condensed into a spot, but not far enough to truly get that “out of your head” experience. Imaging is fairly accurate, though center-imaging, as usual for IEMs, suffers.
With the ANC turned on, the sound signature of the WF-1000XM4 barely changes. The ANC also allows listening to the headphones at lower-than-required volumes.
Connectivity ⓘ
- Audio Codec: SBC, AAC, LDAC
- Bluetooth Version: 5.0
- Bluetooth Chip: Not specified
- Auto-connect when: Taken out of the case
- Average drop-outs in an hour: 0-3 times
- Multi-point connection: Yes, with a firmware update
Multipoint support finally arrived in 2023 with the 2.0 firmware. This firmware also reportedly fixes some of the battery drain issues that users have been facing.
Waterproof ⓘ
- IP Rating: IPX4
The IPX4 rating means that the WF-1000XM4 are secure from minor splashes and water sprays, but there is no dust protection.
Software ⓘ
- Available on: iOS, Android
- 5-band EQ
- DSEE-HX and 360 Reality Audio
- Clear-bass allows for increasing or decreasing sub-bass amount
- Ability to save and import profiles across devices
- Auto Pause: when taken off the head.
The auto pause feature has a bug in the latest firmware where the earbuds sometimes switch to mono mode if one of them is removed during playback. As such, I have disabled it for now. If you encounter mono audio from the WF-1000XM4, turning off auto-pause will fix that.
Comparisons
vs Final ZE3000
The Final ZE3000 is the entry-level TWS IEMs from Final Audio, priced around USD$100 less than the Sony WF-1000XM4.
With the price cut, you forego app support, ANC, wear detection, and other smart features exclusive to the Sony pair. Bummer. If you need ANC and such, you can skip this section entirely. However, if you prioritize sound quality, read on.
The Final ZE3000 have been outpaced so far, but they gain back momentum with their sound quality alone. Simply put, the ZE3000 are more resolving than the WF-1000XM4, and the bass is tighter and faster with better texture.
The mids have outstanding clarity, and the treble has noticeably more sparkle. Staging is very wide, even when compared to wired IEMs. Imaging is also touch more precise. Stage depth and overall smoothness of the sound are the only areas where the Sony pair has the upper hand.
If you only need good sound, save the extra bucks and get the ZE3000 – they simply sound better. If you need all the smart features, the WF-1000XM4 are hard to beat.
Conclusion
Sony has managed to create one of the most feature-rich TWS IEMs with the WF-1000XM4. Given that the smart features work irrespective of the platform (something Apple Airpods and their variants can’t say), the WF-1000XM4 further distinguish themselves from the pack.
Some aspects are still under construction. ANC on IEMs is less performant than on full-size headphones (i.e., no filtration of high-frequency noise), the overall technicalities could be better, and the price is pretty high for a pair of TWS IEMs.
However, if you want all the bells and whistles, you gotta pay up. Based on overall performance, the Sony WF-1000XM4 are among the best TWS IEMs and earn my unreserved recommendation.
Personally I think this review hits all the marks. Having owned XM4s for a while now, my biggest gripes are the lack of multipoint, the limited customizability of the controls, and the steadily decreasing battery life.
I have not owned them long enough to notice the battery life decrease, but it seems this has been a common problem.
Got it a year ago and have issues from day one. NC performance is poor, unless you use a too big of foam.
Even worse. Today the battery lasts only 20 minutes on the right and 40 on the left. I read many users have this issue. Don’t get a Sony before you read the truth about it.
I second this. After a year, the battery on the right earphone is dead and won’t even charge. A month before that it overheats when charging. Waste of money.
I used them for about two months before writing the review, so I did not notice any battery life issues. But it appears this is a common problem. I will add a note in the battery life section in the review.
Yeah, this review is accurate… except for one thing … longevity.
These buds have a design flaw that makes them useless with ~12 months heavy use.
The earbuds have a primary bud which does the heavy comms work with the phone. The bud chosen is supposed to vary based on which one has the best signal.
What happens in practice with these is it tends to stick with one, and drains that one a noticeably quicker. The result is heavier charging/discharging on the primary, compounding over time, to the extent my left buds battery is dead after 30 minutes use, with 70% left on the other.
Mine is far from an isolated case (check Reddit) and seems to be an xm4 problem, as the xm3s didn’t have this.
Your milage may vary. I used them 3-4 hours a day average, and tended to keep my phone in my left pocket most the time, hence the left bud took the beating solo.
12 hours is definitely possible with only the SBC/AAC codec and ANC off. I still get like 9 – 10 hours (approximately) on mine with ANC off.
Still no multipoint update available and it doesn’t look like it’s coming as the wf-1000xm5 are close to being released.
Thanks to the new update, my right side goes from 100% to 35% in almost 2 hours, making these useless now. They caused this with the multipoint update.