Sony WF-1000XM4 (Black) review

The Black WF-1000XM4 is an earlier Sony sealed in-ear noise-canceling model, not a current-generation equivalent merely because the product name resembles later XM versions. Sony's US product page identifies the black model, while its current status page labels the item no longer available. The analysis below uses Sony's specifications and model guide; it is not a listening, fit or battery test.

Sealed fit is part of the noise-control system

This design uses tips that sit in the ear canal. Sony's guide lists three supplied noise-isolation tip sizes—S, M and L—with M attached at purchase. It explains that a poor fit can affect noise cancellation, sound, calls, touch operation and voice features, and recommends checking tip fit in the Sony app. The tips are foam-based consumables rather than interchangeable proof of comfort: their condition and exact sizes matter, especially in a used or open-box offer. The left and right ears may need different sizes. None of that predicts an individual seal.

The model has both noise-canceling and ambient-sound functions. Sony's guidance describes ANC as most useful for certain steady, lower-frequency sounds rather than a promise to eliminate every voice or sound. A snug tip can help passive isolation, but the fit instructions should be treated as a practical check, not as a performance guarantee. Sony's current official support tutorial also lists the WF-1000XM4 among its true-wireless multipoint examples; a separate Sony Q&A page tagged to this model says multipoint is not supported. Because those official support records conflict, check the app and software version on the exact unit before making two-device switching a deal-breaker.

Codec choice changes the ANC battery ceiling

Sony's US specification lists SBC, AAC and LDAC, while the model-specific Help Guide gives a more useful battery table. With noise cancellation on and DSEE Extreme off, its maximum music times are 7.5 hours on SBC, eight on AAC and five on LDAC. With DSEE Extreme set to Auto, the corresponding claims fall to 5.5, six and 3.5 hours. These are published maxima under distinct settings, not expected runtimes for every phone or a result measured here. Sony also notes that wind reduction, Speak-to-Chat, equalization, voice-assistant activation, playback conditions and use can shorten the time.

That makes the XM4 a concrete example of why a generic “up to eight hours” line is not a safe answer for every codec. If you need a five-hour ANC session while using LDAC, the guide supports that boundary only with DSEE Extreme off; a six-hour LDAC minimum exceeds Sony's listed maximum even with that setting. The host must support LDAC and the app must be set to Sony's sound-quality mode. If battery headroom matters more than LDAC, compare the AAC or SBC row instead of borrowing its number for LDAC.

Multipoint, codecs and the host need separate checks

The WF-1000XM4 Help Guide documents the app's “Connect to 2 devices simultaneously” setting, with playback switching between two hosts and call standby on two phones. It does not describe two audio streams playing at once. Its operating-time table and multipoint instructions are separate; the reviewed evidence does not establish a codec-specific runtime while two hosts are connected, so this assessment does not combine a two-device claim with an LDAC battery plan. Bluetooth version is 5.2. The source device, app version and selected codec still determine which route is actually used.

For a nearby generation comparison, the current-reference WF-1000XM5 keeps SBC, AAC and LDAC but also documents LC3 under LE Audio in its own manual. That added route is a real functional distinction; it does not establish that an XM4 can use LC3 or that one model will fit or sound better. Compare each model's own manual and host requirements rather than transferring newer features to this earlier product.

Wireless charging is not water protection

Sony specifies USB-C case charging and Qi wireless charging for the XM4; a wireless charging pad is not part of the listed package. The same sources distinguish the parts clearly: the earbuds have water resistance equivalent to IPX4, but the case is not water resistant and the headset cannot be used in water. Sweat or splashes do not turn the case into a rated component. Dry the units and contacts before charging, follow the model guide, and do not use an IPX4 label as permission to swim or shower with them.

Sony's package-content page lists the charging case, short USB-A-to-USB-C cable and S/M/L foam tips. It describes the original model package, not what a resale listing contains today. A buyer should verify that the actual offer includes both earbuds, the matching case, usable tips and any cable they expect; check the seller's return and warranty terms separately.

Who should keep it on a shortlist?

The XM4 is a documented earlier option for someone specifically willing to assess a sealed ANC design, its codec-dependent runtime and the exact used or remaining-stock offer. Its relatively simple route to a five-hour LDAC floor is useful only if DSEE is off and the host supports LDAC; its AAC figure reaches eight hours with that same setting off. The case adds Qi, but its splash rating remains earbuds-only. Sony's US page says this item is no longer available, so no current seller, battery condition, stock or price is inferred here.

Before treating it as a match, confirm the generation and black configuration, inspect battery condition and foam-tip state, verify the case and charger, and test whether the exact device/software combination exposes the multipoint setting you need. This is a source-based model assessment, not a claim of ownership, hands-on use, measured cancellation or tested call quality.

Primary references: Sony's US WF-1000XM4 Black product page, US specifications, operating-time table, package list, wearing guide, multipoint guide and US product-status page.