Hear at last: Sony’s WF-1000XM4 TWS IEMs

The audiophile headline for Sony’s latest generation of true wireless IEMs – the WF-1000XM4, announced this week – is the inclusion of LDAC support where a strong connection between smartphone and headphone can net 990kbps Bluetooth throughput. That’s not enough for CD-quality audio and a long way from hi-res audio’s data demands but it is enough to sound very good indeed. LDAC’s data rate will automatically drop back to 660kbps and 330kbps as the connection weakens. Bluetooth codec trainspotters will recall that the WF-1000XM3 supported only AAC (and SBC).

Like DAC chips used inside D/A converters, a Bluetooth codec’s data rates give us numbers: something solid upon which we can hang our online opinions and prejudices should we fail to notice (or quantify!) the improvements made elsewhere by Sony. The XM4’s hardware feature list – one that includes a new 6mm dynamic driver, an improved active noise cancellation fed by two microphones (one feedback, the other feed-forward) and an all-new Bluetooth SoC (Integrated Processor V1) to tie the whole lot together – will impact sound quality more than any Bluetooth codec. After all, what use is a higher-resolution codec if the hardware won’t let us hear its benefits?

A bonus for those who dig faux-surround sound, the XM4 will also render 360 Reality Audio when supplied by Deezer, Nugs or Tidal’s Android and iPhone apps.

Carried over from the previous generation – the WF-1000XM3 – the XM4 are: IPX4 water-resistant; offer Google/Alexa voice assistance; will auto-pause when removing an earpiece; have touch controls; will automatically tailor the ANC according to the listening environment; deliver quick attention mode when covering one earpiece with a hand; promise an 8-hour runtime from a single charge (with 16 more from the carry case) and a 5-minute quick charge will, according to Sony, return 60 minutes of playback time. Qi wireless chargers can also apply.

The most radical change of all we’ve saved until last. Sony has completely reworked the XM4’s earshell to dispense with the XM3’s fins for a tidier and more conventional-looking true wireless IEM. The eartips that quite literally seal the deal have also been redesigned.

From the press release: “The new headphones combine a shape that matches the ear cavity with a new ergonomic surface design for a more stable fit. Using the Sony | Headphones Connect App, users can now take a few simple measurements to find the ideal size of Noise Isolation Earbud Tips8 to ensure maximum sound quality and minimum outside noise. The new earbud tips are made from a unique polyurethane foam material that is soft and elastic, which improves adhesion to the ear canal, eliminating gaps to insulate sound and reduce noise. The headphones are also lighter and 10% smaller than their predecessor, with a 40% smaller charging case.”

The WF-1000XM4 are available now for €279 / US$279.

Further information: Sony