Bose Ultra Open Earbuds Truly Wireless Headphones Review

The manufacturer's take on what open earbuds look like and how they fit is unique. While their previous effort, the Bose Sport Open Earbuds Truly Wireless, align with the current slew of over-ear hooked unsealed wireless earbuds, the Bose Ultra Open Earbuds are a completely different take on open fits. Rather than hooking over the top of your ears, they clamp just above your ear lobe around the bottom of the helix, antihelix, and pinna, sort of like an oversized clip-on earring.

The open earbuds are made of plastic and silicone and come in two standard colors, 'Black' and 'White Smoke'. In addition, Bose collaborated with the clothing company Kith to create a branded version in black. The Steve Lacy signature model features the boldest color departure. These have green buttons, with one bud in cream and the other in a darker earth tone. These come with a matching two-tone case with dark magenta branding.

The Bose Ultra Open Earbuds are impressively comfortable. They feel good thanks to their lightweight, small size, and nearly universal sizing. They take some getting used to, though, and initially, dialing in the placement feels strange, but you can adjust where they sit along your ear, so if you wear earrings, you can work around them. Wearing them for long periods can eventually fatigue the pinna of each ear, and if you exercise, they can heat up slightly.

The Bose Ultra Open controls are okay. Essentially, you've got a single, clicky button on each bud for all of your controls, which is intuitive but inherently limited in commands. They emit sounds to signal they're powered on when you take them out of their case, to alert you if you've maxed out or minimized the volume, and there are voice prompts. They don't make sounds when you use playback controls like pause, play, and track skipping. All the commands work well except for volume adjustments, which have a narrow window of time for getting the level you want without over or under-shooting how long you need to hold the button down. You can assign each earbud one preset function per side through the companion app, called 'shortcuts,' like cycling through Immersive Audio settings and accessing your voice assistant. We experienced issues remapping controls when we placed the buds back into their carrying case. This action caused the buds to forget the remapped commands, so it can be frustrating if you're constantly losing your saved setup.

Multi-function button:

• Press and hold: Power on/off.
• Press and hold from powered off: Turn on and initiate Bluetooth pairing.
• Single press: Pause/play, answer call/answer a new incoming call (while you're already on a call).
• Double press: Skip to next track, end call/decline incoming call
• Double-press-and-hold: Increase volume on the right earbud, decrease volume on the left earbud.
• Hold: One assignable function for each bud.

The Bose Ultra Open Earbuds are exceptionally portable. You'll still want to use their case to store them, but they take up very little space.

Their charging case is good. It's similar in looks and build to other true wireless cases by the brand, with magnets to hold the buds in place to charge. Its materials are semi-matte plastic. The plastic hinge noticeably shifts laterally, which doesn't instill confidence in its long-term durability. For premium earbuds, it's somewhat surprising the case doesn't charge wirelessly. However, it charges via the USB-C port on the rounded bottom of the case.

The Bose Ultra Open Earbuds' build quality is good. Their plastic housings and the buttons feel solid. The open-fitting buds have an IPX4 rating to protect against light splashes, but the case doesn't. As with most designs, their potential points of weakness are the hinges. The flexible silicone that loops each cuff-like bud around your ear has the potential to tear or weaken over time, as does the internal cabling that routes through the silicone loop. Similarly, the plastic hinge on the case has a noticeable amount of give, and the lid shifts around somewhat.

The Bose Ultra Open Earbuds are incredibly stable. They overcome some of the fit-related shortcomings of conventional true wireless designs. For example, by not needing different-sized ear tips to obtain a good fit—and fit still varies from person to person, even when you get a huge selection of ear tips—this wraparound shape is more predictably stable. You can successfully perform jumping jacks, push-ups, or go for runs without needing to adjust them. These are great if you have trouble getting earbuds to stay put.

• Bose Ultra Open Earbuds
• Charging case
• USB-A to USB-C charging cable
• Paper warranty pamphlet

The Bose Ultra Open Earbuds have a very bright default sound. Part of that is attributable to their open fit that sits outside your ear canal. How they sound depends greatly on how much your environment competes with what you're listening to with the buds. Their tuning works for any spoken content like podcasts or classical, folk, and vocal-centric pop music without a lot of bass content. By design, these can't adequately reproduce deep, rumbling low and mid-bass frequencies enough to balance their frequency response.

To compensate for the steep bass roll-off, the high bass is somewhat boosted, so the attack of picked bass guitars has some boom, but they lack weight. Their mid range sounds smooth on lead instruments. Most of the treble range is exaggerated, leading to harsh and piercing sibilants (S and T sounds) that can cause your ears to prematurely fatigue. This would sound like a lot of treble even if more bass were present in the tuning, and without much low-end, it's even more shrill. You can use the in-app EQ to turn down the treble, although it's limited to three band and has imprecise labels like 'treble.'

These headphones have a high noise floor, which is noticeable if you're in a quiet environment. It's most prominent when audio content is playing, and if you pause it, you'll hear the hiss continue for a couple of seconds before disappearing until you play audio again. It seems like our left bud also has a louder noise floor than our right bud. External noise, like a busy street, can help mask the sound.

Their frequency response consistency depends on your ability to get each to have the same ear placement. Due to their unique fit, you can move them around more than conventional earbuds. If they sit differently on each ear, it'll impact the delivery of consistent treble and bass. Since not everyone has identically shaped ears, you'll want to listen for consistency, too.

While it looks like they're inconsistent in the bass frequencies because they barely reproduce much lower than the high-bass register (which is quite consistent), it doesn't make much difference, effectively. Mids are consistent between wears and wearers. Treble is delivered with inconsistencies between wearers, which is pretty normal.

Weak bass is one of the disadvantages of this style of open-fitting earbuds, and, as a result, these buds do a terrible job of following our bass response target. For instance, the Shokz OpenFit True Wireless struggle with the same limitation because they leave your ear canals unsealed, so this isn't unique. These buds slightly boost the high bass, so you'll hear the initial strike of a kick drum and pluck of a bass string in post-punk songs like Transmission by Joy Division, but they lack body and substance.

The Bose Ultra Open Earbuds do a remarkable job when it comes to reproducing mid-range frequencies. These have a smooth and slightly forward mid-range voicing that doesn't significantly exaggerate any ranges. Lead instruments like guitars and keyboards sound clear and natural. Spoken voices in podcasts and audiobooks come through true-to-life.

The Bose Ultra Open Earbuds' compliance with our treble target is sub-par. Compared to the previous open earbuds by the manufacturer, the Bose Sport Open Earbuds Truly Wireless, these have very piercing and harsh treble. As a result, the harmonics and top-end airiness of cymbals, vocals, and S and T sounds sound crisp and shrill. It's possible this exaggerated treble attempts to add clarity where it can get veiled by your environmental sounds reaching your ears. Fortunately, you can turn down the 'Treble' slider in the app's equalizer, although it's not a very granular EQ.

These headphones have a sub-par peaks and dips performance. Unsurprisingly, there are a few peaks/dips in the bass range, including a large peak in the low bass; these headphones already have some trouble reproducing this range. It's also worth noting that their unique design interacts with your ears differently than over-ears or in-ears, so you aren't getting quite the same bass delivery either. These peaks/dips depend highly on your fit, but they won't impact your listening experience too much overall.

There are some other peaks in the mid and high-bass to add low-end emphasis, which is otherwise missing in the frequency response. Kicks come across okay, given the high-bass focus, but they don't have the weight a full low-end extension would ordinarily supply. This peak evens out for most of the midrange with small deviations, and lead parts like synths and guitars sound natural on the whole. The treble range features some sharper deviations from the sound profile, with a small peak in low-treble that reduces the presence of sibilants, followed by a dip in the mid-treble that takes away some of the airiness of cymbals and vocals. There are some large peaks and dips in the high-treble range, too, but we lose sensitivity to this range over time, making them hard to hear.

These have poor imaging, which is expected to an extent with these kinds of open earbuds. Their significant group delay is audible as loose-sounding bass, and the buds struggle to reproduce low frequencies. You'll notice it in real-life content because low notes won't sound tight. Our unit also exhibits phase mismatch, notably in the bass range, but this doesn't impact the placement of objects in the stereo image much. Still, because you can easily place these earbuds in slightly different spots along your ears, it's harder to determine in real-world circumstances if the discrepancy between the L/R driver results from phase mismatch or a slightly different placement along your ear.

In all, these results indicate their ergonomics are not perfect, specifically in the bass region. It's hard to directly compare our unit (because of open earbuds' inherent design limitations) with other conventional headphones by the manufacturer, which otherwise has good quality control. Imaging varies from unit to unit, so these results are only valid for our unit.

Their passive soundstage is bad. Because the drivers sit outside your ears towards the bottom of your ear, they don't interact with your ear's pinna for an immersive listening experience. However, they're open-fitting, so they have an unnaturally open quality but aren't immersive.

Their virtual soundstage is accessible through the companion app. The manufacturer calls the surround sound mode 'Immersive Audio.' This essentially applies digital signal processing (DSP) to force conventional stereo mixes into a simulated virtual surround sound. It's similar to Apple's Spatialize function (not to be confused with Spatial Audio). Unlike other surround sound implementations, like Sony 360 Reality Audio and Apple Spatial Audio, this effect doesn't require your audio to be specifically mixed by an engineer or producer in surround sound formats like Dolby Atmos.

You get two basic modes: one that applies the algorithm to force your audio into Immersive Audio, which holds the center of the surround sound effect in a static position. The other mode adjusts the surround effect with head-tracking relative to where you are and the virtual 'center' of the audio. The effect works pretty well and is immersive for content like live concert recordings, and it's fun to try on old mono recordings. Still, it's DSP, so it works better on some songs than others because a producer isn't making the final mixing decisions. However, since not all of your favorite tunes will receive a dedicated Dolby Atmos mixing treatment, the DSP effect of Immersive Audio is a close approximation.

The Bose Ultra Open Earbuds' weighted harmonic distortion is passable. They exhibit distortion in the mid-bass, where the bass tapers off in the frequency response, and a fairly even amount of distortion in the mids through the low treble. As a result, your audio won't sound totally clean and pure. Because most people wear these to stay aware, it's unlikely that you'll notice the distortion, as it's comparatively subtle in the context of going about your day while the wider world's noises reach your ears.

These are the settings used to test these headphones. Our results are only valid when using them in this configuration.

The noise isolation of these open-fit earbuds is awful, which is a feature and not a bug. Their goal is to leave your ears open so that you can stay aware of your environment while still listening to your audio. As a result, virtually anything you can hear normally can still be heard with these on, so rumbling bus engines, traffic, chatter, and café clatter all reach your ears. If you're out running or working in a collaborative office space, you can seamlessly hear what's important without pausing your music.

In the app's settings, you can also select that the volume you listen at automatically adjusts to your surroundings' noise level. This feature isn't unique to open-fit earbuds, and you can find it in products like the Google Pixel Buds A-Series True Wireless. Still, it offers more utility with earbuds that totally lack isolation because your audio contends with even more external sounds.

True to their design, the Bose Ultra Open Earbuds allow you to hear everything in your environment because they have virtually no isolating qualities. If you're outside on the street for a run, this open-fit keeps you completely aware of your surroundings. However, they're a terrible choice for ignoring passengers and ambient din on a flight or focusing on work in a busy office.

The Bose Ultra Open Earbuds have a decent leakage performance. Leakage is mostly concentrated in the treble range, so escaping audio sounds thin but is audible, even if you're in a moderately noisy environment, like an office. However, this is still a marked improvement over the previous Bose Sport Open Earbuds Truly Wireless.

The Bose Ultra Open Earbuds' microphone recording quality is alright. As of firmware update 4.0.22, the mic sound quality has improved. Your voice sounds a bit too bright, but overall, there's a somewhat balanced midrange, so you sound mostly true-to-life.

The microphone system's noise handling is decent. Firmware 4.0.22 improves the noise handling a bit. With constant background noise, the mic prioritizes your voice and doesn't dramatically impact the clarity of your speech. Background voices are filtered well, though some of the high frequencies of your voice are also removed. It also suppresses the sudden loud noise well without greatly obscuring your voice.

These have a very good battery performance. The manufacturer states that they have a 7.5-hour battery life, and our unit lasts for 9.5 hours of continuous audio on a single charge. Your results may vary based on factors like how loud you listen to your music, and similarly, the manufacturer states these will last 4.5 hours when you listen using Immersive Audio mode. Their charging case holds just under three extra charges, and they take less than an hour to charge up fully. Interestingly, the case doesn't have wireless charging compatibility and only uses USB-C. To help conserve battery life, they also feature an auto-off timer. That said, if you want even better battery life from clip-on earbuds, check out the Anker Soundcore C30i True Wireless.

The Bose Music app is decent, but it has a couple of issues. Its interface is clean and easy to navigate with solid features, have a look at it here. There's Immersive Audio, a DSP-based virtual surround sound effect with head-tracking. You can control the somewhat limited three-band equalizer with presets and playback and volume controls. You get 'shortcuts,' which are assignable commands for the press-and-hold command on the buds. In the app, you can monitor battery levels and access firmware updates. The manufacturer typically rolls out new features to existing products through these firmware updates.

Unfortunately, connecting to the app can also cause the buds to disconnect or take time for the app to search for them. You can erase the app cache and re-pair the buds as one solution, but it doesn't completely solve things since the issue could still happen again. We didn't experience this issue on all phones, though, and noticed it on the Samsung S24 Ultra, so your experience may vary.

We also noticed that the controls would reset after you placed the buds back into the case. While you can remap controls to your liking in the app, if you lose these settings by using the carrying case, it can be a dealbreaker.

These headphones have a USB-A to USB-C cable for charging their case's battery. You can't listen to these with a wired connection.

The Bose Ultra Open Earbuds have alright Bluetooth connectivity. They use Bluetooth 5.3 with a good selection of codecs, including aptX Adaptive (High Quality and Low Latency). AptX Adaptive (Low Latency) can still cause a bit of lag to audio when watching videos, but not a huge amount. Latency varies from device to device, and some apps compensate for that. aptX Adaptive (High Quality) offers high-quality audio, although whether you can truly detect the quality difference depends on how noisy your environment is. They don't have quick pairing, and at launch, they don't come with multi-pair capabilities, although Bose indicates that will change in a later firmware update.

The Bose Ultra Open Earbuds can connect to computers that have Bluetooth compatibility. Full audio and microphone support is available.

The earbuds come with a charging case with a USB-C port for charging.