OPPO Enco X4 Review Finds Flagship-Class ANC Alongside Audible Noise Floor

According to the outlet, the default deep noise-cancellation setting recalculates in real time, adjusting ear pressure and low frequencies gradually over roughly seven to eight seconds rather than abruptly dropping to a weaker mode. The reviewer placed the X4's cancellation depth and effective bandwidth in the same tier as the vivo TWS 5 Pro, Huawei FreeBuds Pro 5 and Samsung Galaxy Buds4 Pro, while Sony's WF-1000XM6 and Apple's AirPods Pro 3 retained an edge. On subways, trains and planes, the X4 suppressed steady mechanical noise less effectively than those models, though the gap was described as modest. The reviewer ranked it within his "In-Ear Skyline Level."

The noise floor drew the clearest criticism. On firmware version 116.116.199, the review said, both noise cancellation and transparency produced a hiss noticeable on first listen, even to a reviewer who described himself as insensitive to the issue. The article said this could be a defect specific to the test unit but listed it as a clear reservation.

For calls, OPPO equipped the X4 with a VPU bone-conduction microphone and a 6nm NPU for AI noise processing. The company claims resistance to level-seven winds, and in the review winds from three directions had little effect on voice clarity or continuity. On a carrier network, call audio was moderately loud and clear, with a slightly dull timbre and obvious suppression of surrounding noise, the review said.

The earbuds support interpretation across more than 20 languages for up to 5,000 minutes a month, accessible on third-party phones through the HeyMelody app. The reviewer found Chinese-English, Japanese-English and Chinese-Japanese translation returned results quickly when speech was picked up by the earbuds, though phone-side pickup occasionally failed on long sentences and cut in early. Other smart features include fixed voice commands, which recognized Mandarin well but struggled with the Taiyuan dialect, head gestures, cervical health tracking and conversation awareness that fades playback back in about five seconds after speech stops.

The X4 comes in soft white, titanium gray and pink gold; the titanium gray unit reviewed showed a faint purple tint. The stems use a sandblasted metal finish with a Dynaudio co-creation mark, and the earbuds carry an IP55 dust and water rating. The charging case is plastic with a sandblast-like texture and a soft-touch coating; the USB-C port sits on the bottom, the pairing button on the right side, and the Qi wireless charging coil is placed on the front face, a position the reviewer called odd.

Controls rely on a raised pressure-sensitive area on the stem side that must be pinched rather than touched, with defaults for play-pause on a single pinch, next track on two, previous on three, noise-mode switching on a long pinch and volume on swipes. The reviewer rated recognition speed and accuracy as top-tier, on par with AirPods and Galaxy Buds, though haptic feedback lagged slightly behind Apple's.

The earbuds support LHDC 5.0 at 1Mbps. Paired with an LHDC One transmitter at 48kHz, packet loss began through a wall at about 9 meters, stayed manageable between 9 and 11 meters and turned into stuttering beyond 11 meters; AAC connections to an iPhone 17 and a Sony Xperia 1 V held stable to about 10 meters. Dual-device connection and Windows Swift Pair are supported, though switching between LHDC and AAC devices was not entirely smooth. The claimed 39ms game mode reduced video latency from about half a syllable to slightly under half a syllable with AAC on the Xperia 1 V, while LHDC at 48kHz stayed at about half a syllable even with the mode on.

In the reviewer's standard battery test, streaming music and podcasts over AAC at 50% volume with noise cancellation off ran for 14 hours 39 minutes on a single charge, above the official rating. Charging drew 1.2 to 2.3 watts early on and settled near 0.9 watts later; Qi wireless charging is supported. Transparency offers a single adaptive level that attenuates high-frequency ambient sound more than AirPods Pro models but sounded natural overall, and its wind-noise handling reduced transparency strength rather than filtering wind as cleanly as deep cancellation did.