Sony LinkBuds S (Black) review

The Sony LinkBuds S is a small, sealed-in-ear noise-cancelling model from the LinkBuds family, but it is not the open-ring WF-L900 or the later LinkBuds Open. This assessment is for the Black U.S. retail configuration WFLS900N/B (Sony's support-family code is WF-LS900N). Sony’s U.S. page identifies that model and now directs visitors toward similar products; a U.S. retailer listing also marks the Black version no longer available new. I treat it as an earlier product reference, not a live offer or promise that a reseller has a complete, healthy unit.

A sealed fit depends on your ear, not the model name

Sony’s specification calls LinkBuds S a closed dynamic design. Its guide says to put each tip into the canal and twist the earbud into place. The supplied package is unusually useful to check by exact size: it lists SS, S, M and LL silicone tip pairs, with M already attached. Sony specifically says the L size is not supplied. A mismatched tip can leave a poor seal, so try the available sizes on both sides and check comfort and noise control during any seller return period; the documents cannot tell me how the shape would feel or seal for a particular wearer. Aftermarket tips also need care because Sony warns that ill-fitting tips can affect charging placement.

Noise cancellation and ambient sound are separate selectable modes. The label confirms the feature set, not a measured reduction in your train, office or street noise. Sony’s U.S. page describes the buds as 0.17 oz each and the case as about 1.24 oz; those published masses may help compare carry weight but say nothing about comfort. The earbud units carry an IPX4 claim, while Sony explicitly says the case is not water resistant. The manual warns that the headset cannot be used in water and gives specific drying steps after exposure. Treat the buds and case separately, and never charge wet contacts.

There are four codec routes, not one battery number

Sony’s YY2950 Help Guide places SBC, AAC and LDAC in Classic Audio, and LC3 in LE Audio. With ANC on, its music table lists maximums of six hours for SBC, six for AAC, 3.5 for LDAC and 5.5 for LC3. With ANC off, the corresponding maxima are nine, nine, 4.5 and nine hours. These figures are tied to the selected route, and Sony warns that settings such as equalizer, DSEE Extreme, Speak-to-Chat, voice features and other automatic functions can shorten runtime. A five-minute charge is listed for about one hour of playback. These are manufacturer conditions, not measurements or guaranteed time for an older battery.

LDAC is not simply a checkbox on the earbuds. Sony says a compatible source is required and the app must be set to sound-quality priority; its factory stable-connection setting does not play LDAC. For LC3, both the headset and Android phone must support LE Audio. Sony’s documented setup changes the app’s LE Audio priority setting, deletes the prior Classic Audio pairing and pairs again. Check the exact host and current setup support before buying around either codec.

Multipoint and LC3 are separate operating arrangements

The guide documents a Classic Bluetooth multipoint mode that connects two devices at once after turning on “Connect to 2 devices simultaneously” in the Sony app. It can switch playback from one device to another without a Bluetooth reconnection, or leave two phones available for calls. It does not mean simultaneous mixed audio. Sony’s app list marks multipoint as unavailable in LE Audio, so the LC3 route and two-device route should not be treated as a combined setup. Sony does not publish an ANC runtime tied specifically to multipoint, so I do not transfer the one-source SBC or AAC numbers to that mode.

Charging and package details matter for an older listing

The help guide describes charging the case through its USB-C port with the supplied short USB-A-to-USB-C cable. It gives about three hours to charge the empty case and earbuds together, and about two hours for the earbuds alone. Sony’s support specifications identify USB charging with the case. I found no authoritative evidence establishing wireless charging for this exact Black case, so leave that feature unassumed and verify it separately if it is essential. Sony’s official package list includes both earbuds, case, cable and tip pairs; a retailer photo cannot prove that a used or refurbished box still has every item.

Who should compare it—and what to verify

The LinkBuds S remains a relevant earlier comparison for someone seeking a sealed ANC earbud and a choice among Classic Audio codecs, especially if the six-hour SBC/AAC maximum is sufficient. The shorter LDAC ceiling and distinct LC3 mode are important if codec and endurance are both hard requirements. Compare the later LinkBuds Fit if you want a related but separately configured tip-and-supporter design, or the WF-1000XM5 for Sony’s higher-tier ANC line; neither family’s feature details should be transferred to this model.

Before considering an earlier listing, match WFLS900N/B rather than relying on the shared LinkBuds name. Ask for the exact finish and case, inspect the tips and charging contacts, verify both earbuds pair and charge, and check battery condition, seller, return terms and warranty. No hands-on comfort, ANC, call, sound or battery test was performed for this assessment. Read the Sony LinkBuds S Help Guide and current U.S. support pages for the exact host, firmware and care instructions.