Based on firmware updates to the OnePlus Bullets Wireless Z2 ANC, the above actions may be slightly modified, and the actual OTA content may differ from that specified.

The larger 12.4mm drivers are a major differentiator between the OnePlus Bullets Wireless Z2 and the Bullets Wireless Z, and this has made a positive difference to the sound quality. The sonic signature in particular sees some changes, with the Bullets Wireless Z2 sounding a bit more punchy and driven, while maintaining the reasonable level of detail and clarity that the original Bullets Wireless Z introduced to the budget audio category in 2020.To ensure the normal use of your earbuds, update your Wireless Earphones (ColorOS 11 or later, OxygenOS 12 or later), OnePlus Buds (OOS 11), or HeyMelody (Android 7.0 or later, iOS 13.2 or later) app to the latest version using your local app store. Enabling automatic updates is recommended to ensure you can use the latest software and functions. IP55 rating and IPX4 rating achieved on test date: June 11, 2021. Data is based on test results using TÜV SÜD based on IEC 60529:1989, A1:1999 and A2:2013 test standards. Water and dust resistance may be reduced as the device ages. Liquid and dust damage are not covered under warranty. To top it off, the treble performance is great as well. It shares some of the mellowness of the mid-range so there's no unwanted harshness or sibilance at the cost of some air and brilliance. However, it still comes across as detailed and articulate without being dark or muddy. OnePlus Bullets Wireless Z2 has 16 hours of talk time and with a standby time of 80 hours on a single charge. Endurance test data is based on OnePlus laboratory tests conducted at 50% volume. Specific endurance performance will vary based on actual conditions and is affected by volume, output source, environmental interference, product features, software versions and usage habits.

What's disappointing, though, is the transparency mode, which sounds muffled and not particularly transparent. It's fine if you just want to walk around without completely being oblivious to your surroundings but I still found it better to just unplug the earbuds to hear better. The headphones are certificated for IP55 dust and water resistant. Please avoid using the headphones during strenuous exercise or while in humid environments. Water damage is not covered under warranty. Sweat resistance follows the same principle as water resistance because the headphones can help prevent liquid, including sweat, from entering inside. We also applied special processing to the innards in prep to enhance sweat resistance capability. However, sweat resistance capability will decrease with long-term use. Sweat damage is not covered under warranty. The Bullets Wireless Z2 ANC have mediocre audio quality by default. The sound is the same overwhelming bass-heavy assault that has now become the OnePlus house sound.The new ANC mode on the Bullets Wireless Z2 ANC also worked reasonably well. It does its best with low-frequency sounds, so things like the sound of an aircraft or bus engine, while also being decent for household sounds such as air conditioners and fans. It doesn't do so well with mid and high-frequency sounds but that's generally the domain for bigger and more expensive headphones. Finally, connectivity performance was stable with the Bullets Wireless Z2 ANC and there were no observed issues with connection quality or stability. Battery and charging Latency can be reduced to as low as 94 ms when paired with select OnePlus phone devices, with Pro Gaming mode turned on.

The microphone performance on the Bullets Wireless Z2 is good. There is audible compression when speaking even in quiet environments but voices still sound relatively clear with good tonality. In noisier environments, the AI scene-model algorithm does a good job of reducing ambient sounds and prioritizing the voice, which sounds fairly similar to speaking in quiet environments. OnePlus claims a latency of minimum 94ms when paired with select OnePlus phones, although it fails to mention which exact OnePlus phones, how the headset achieves this lower latency, and what the latency is with other devices. The tonality of the sound is similar to OnePlus' recent products, with neutral-leaning mids and treble and over-the-top bass. The Bullets Wireless Z2 has exceptional battery life. During my battery drain test, the headset ran continuously for 28.5 hours, which is very close to the 30 hours claimed by OnePlus. After a ten-minute charge, the headset went on for 20.4 hours, which is just over the 20 hours claimed by the company. With normal use, the headset should last well over a week on a single charge. ConclusionThankfully, the six-band custom EQ does help out a lot. Using the preset shown above, I was able to get a much more balanced tuning going, which then helped focus on other aspects of the sound. Unfortunately, both the custom EQ and the more sane presets require the installation of the app, which many people never bother with. The mid-range can be good when it is not being masked by the bass. Vocals have a good timbre, if slightly too warm and stuffy, and can be quite pleasant at times. The Bullets Wireless Z2 is a comfortable headset. The ear tips are made out of soft rubber and have the oval design found on the OnePlus Buds Pro and Buds Z2. They fit the ears well and can stay there for hours without being uncomfortable.

On OnePlus phones, the earbud functions can be controlled directly through the Bluetooth settings without having to install a separate app. Product images and display contents are illustrative only. Actual product and display contents may vary.

Bigger drivers on the OnePlus Bullets Wireless Z2

There is also a multi-function button provided, which actually just does two things. You can press and hold it to start the pairing mode or you can double-press it to instantly switch to the previously connected device. All the buttons work well and have a good quality feel to them. OnePlus Buds Z2 and OnePlus phones, when used together, will provide the best experience. OnePlus Buds Z2 are also compatible with Bluetooth® devices; the longest Bluetooth® transmission distance is 10m between OnePlus Buds Z2 and the Bluetooth® device. Due to the nature of Bluetooth®, electromagnetic interference in the area may cause the connection to break. Switching ANC modes only has a small effect on the audio quality. The sound is ever so slightly brighter and less bass-heavy with ANC off compared to on, and then further slightly brighter with transparency mode enabled. In my testing, the Bullets Wireless Z2 ANC lasted for 19 hours and 38 minutes with ANC enabled and 27 hours and 7 minutes with ANC disabled. After a 10-minute charge, the earbuds played for 14 hours and 36 minutes with ANC enabled and 20 hours and 21 minutes with ANC disabled.