The Bose SoundLink Flex is a small portable Bluetooth speaker that can accompany you everywhere from house parties to picnics. Its IP67 rating certifies it to be fully dust-tight and immersible in up to a meter of water for 30 minutes, meaning you can bring it outdoors without issue. Wherever you go, its PositionIQ technology adjusts the speaker's audio reproduction to meet the unique acoustics of your space.
Our Verdict
The Bose SoundLink Flex is acceptable for music listening. Out of the box, this small speaker reproduces voices and lead instruments with detail and clarity, so it's suitable for most genres. EDM fans might mourn the loss of low-end thump, but that's the compromise you make for speakers this size. It gets loud enough to fill an average-sized room with sound, but it won't be the best choice for blasting the hits outdoors at your summer BBQ. Its app lets you pair it with other Bose speakers but lacks customization tools, so you can't customize its sound to suit your preferences.
- Good performance with dialogue.
- Requires two units for stereo audio.
The Bose SoundLink Flex is middling for videos and movies, but it's not really designed for this purpose. While it can reproduce dialogue with clarity, on its own, it can't reproduce cinematic low-end rumble or immersive stereo soundscapes, and if you turn it up to try and compensate for this, your audio will get compressed. It also has some latency issues, especially when paired with iOS devices, so you might encounter lip-sync issues. That said, different apps and devices compensate for latency differently.
- Good performance with dialogue.
- No graphic EQ or presets.
- Compression at max volume.
The Bose SoundLink Flex is good for podcasts. Its mid-range is virtually flat, so dialogue is rendered accurately and with plenty of detail. With its portable design, you can easily take your shows with you from room to room. It's loud enough to fill an average-sized room, but not quite loud enough to fill more open spaces like basements.
- Outstandingly portable.
- Can be paired to two devices at once.
- Good performance with dialogue.
- No graphic EQ or presets.
The Bose SoundLink Flex doesn't have built-in voice assistant support, but if you have a smartphone with Google Assistant or Siri, you can pair it to the speaker to control it with your voice. It does a passable job at this. Amid a noisy party, it doesn't have any trouble hearing your commands, and it can also pick them up from further away.
- Excellent far-field performance.
- Voice assistants aren't built-in.
This speaker is decent for the outdoors. It's easy to bring along with you thanks to its small and lightweight design. It's rated IP67 for dust and water resistance, so it'll withstand a day at a dusty park or a drop in a puddle. With a battery life of over seven hours, it'll get you through most days on the go. That said, its directivity isn't the best and doesn't get as loud as other speakers we've tested, so it won't fill your whole backyard with sound. If you do try to push up its volume, your audio will get compressed, too.
- IP67 rating for dust and water resistance.
- Outstandingly portable.
- No graphic EQ or presets.
- Compression at max volume.
Changelog
-
Updated Oct 31, 2024:
We referenced the Bose SoundLink Flex (2nd Gen) in the App box.
-
Updated Oct 24, 2024:
We updated this article to align with our current standards and edited the text for clarity.
- Updated Sep 27, 2024: This review has been updated to mention the Ultimate Ears BOOM 4 in the Battery and Frequency Response Accuracy sections.
- Updated Aug 15, 2024: We've added a comparison between this speaker and the Beats Pill in Wired.
Check Price
Differences Between Sizes And Variants
The Bose SoundLink Flex comes in six color variants: Black, White Smoke, Stone Blue, Cypress Green, Chilled Lilac, and Carmine Red. This review represents the test results for the 'Black' variant; this is our version's label. We expect our results to be consistent across the various variants.
You can also find a version of this speaker called the Bose SoundLink Flex SE, which comes without a microphone.
If you encounter any other variants of this speaker, please let us know in the comments, and we'll update our review accordingly.
Popular Speaker Comparisons
The Bose Soundlink Flex is a small, portable speaker akin to the Bose SoundLink Micro and the Anker Soundcore 3. It's better built than both of those, thanks to its solid and sturdy materials. Like other SoundLink speakers we've tested, the Flex supports voice assistants through your smartphone, and it does an excellent job of understanding your commands from far and in noisier settings. That said, the SoundLink Flex downmixes your audio to mono, so if you prefer a more immersive sound, the 360-design of the Ultimate Ears BOOM 4 is a good alternative.
The sequel to this speaker is the Bose SoundLink Flex (2nd Gen), which adds a 'Shortcut' button to put the speaker in stereo pairing mode and support for a 3-band EQ in the companion app.
Check out our recommendations for the best Bluetooth speakers, the best waterproof speakers, and the best speakers under $100.
The Bose SoundLink Flex and the Beats Pill are similarly sized speakers with detachable carrying straps. In terms of performance features, there's not a whole lot to differentiate the two. They're neck and neck when it comes to volume, battery life, and portability, and even their default sound profiles are very similar. That said, the Beats has the ability to play audio via a wired source through the USB-C port and can even play back high-resolution content from a compatible streaming service. The Bose supports Bluetooth multi-device pairing though, so choosing between them may come down to which connectivity options you prefer.
The JBL Charge 5 and the Bose SoundLink Flex perform similarly. They both offer neutral sound profiles and are well-built with IP67 ratings for dust and water resistance. The JBL's battery lasts longer than the Bose, though this can vary depending on your usage. However, the Bose is a bit smaller in size and supports voice assistants through your smartphone.
The Bose SoundLink Flex is more versatile than the JBL Flip 6. The Bose supports voice assistants through your smartphone and is excellent at hearing your commands from afar and in noisier settings. It can also produce a deeper bass than the JBL and has a slightly longer-lasting battery life, though this varies depending on your usage habits. That said, the JBL's companion app comes with a graphic EQ to tweak its sound to your liking and offers a slightly wider-sounding soundstage.
The Bose SoundLink Flex and the Sonos Roam 2 are both portable speakers that will appeal to different customers. Both speakers downmix your audio to mono, but the Sonos has much better directivity, so the sound is fairly similar regardless of where you are in relation to it. On the other hand, the Bose produces a bit more bass by default, although you can EQ the Sonos via its companion app, unlike the Bose. But mainly, the Sonos will appeal to people who are already invested in the Sonos ecosystem, especially because the Roam 2 supports the Sonos voice assistant. On the other hand, if you'd prefer to use your device's Siri or Google Assistant, the Bose is the pick for you.
Test Results
This is a small and sleek speaker that you place horizontally, either standing up or lying on its back. It also comes with a built-in strap to suspend the speaker from a hook. The speaker grilles are made out of steel, and the entire speaker is covered in thick silicone.
This speaker is remarkably portable. It's easy to bring with you thanks to its small and lightweight build, and it runs on battery power, so you don't have to plug it into an outlet to listen to your favorite tunes. This speaker comes with a small, thick strap on its side that you can use to suspend it from a hook or attach it to a bag.
The build quality is excellent. It's a sturdy speaker covered by thick silicone, and its drivers are protected by powder-coated steel grilles on its front and rear that are designed to withstand rust, so the paint doesn't flake off. It's rated IP67, certifying it to be fully dust-tight and immersible in up to a meter of water for 30 minutes. While the manufacturer doesn't specify an IK rating for impact resistance, the manufacturer advertises the Flex as rugged and able to withstand being dropped on the floor.
The Bose Flex has a great selection of simple controls. When you turn the speaker on, it informs you of its current battery level and the devices it's connected to. That said, while the buttons are simple to use, they're a bit hard to press compared to the Bose SoundLink Micro and Bose SoundLink Color II's controls because of the thick silicone covering the speaker.
- Power Button: Turns the speaker on/off.
- Volume Buttons: Adjusts the volume.
- Multifunction Button: Press once to play/pause your audio or answer a phone call. Press twice to skip to the next track and three times to skip to the previous track. Hold to decline a call or activate the voice assistant on your paired smartphone.
- Bluetooth Button: Press to activate Bluetooth pairing mode.
The Bose SoundLink Flex has reasonable frequency response accuracy. It comes with Bose's PositionIQ technology, which automatically adjusts the speaker's EQ according to its orientation. We tested it horizontally standing up. It has almost no low-bass, which isn't surprising given its small size, but die-hard fans of EDM might mourn the loss of that low-end thump. Still, the mid-bass is reasonably well-balanced, and a small boost in the high-bass adds warmth to basslines so mixes don't feel thin. Overall, it still has more bass on tap than similarly sized speakers, like the Ultimate Ears BOOM 4. The mid-range is virtually flat so dialogue is clear in podcasts and audiobooks, while instruments are rendered accurately and with detail in even busy mixes. The treble range is also well balanced, with a slight roll-off in the high-treble that doesn't hurt vocal intelligibility or mix clarity. Ultimately, this speaker is suitable for listening to a variety of different audio content.
Its soundstage performance is middling. On its own, this speaker is only capable of playing mono audio, and its directivity is limited to the direction it is pointing in. That means your audio won't sound especially immersive or enveloping, and you might miss out on some details in your audio like reverb and delay tails. You can hook up a second unit to get stereo playback but, even then, this isn't a speaker to choose if 360-degree sound is important to you: its audio reproduction changes greatly depending on your angle to it.
This speaker has acceptable dynamics performance. It gets loud enough to fill a typical living room with sound, but there is a fair bit of compression in the bass region when you push it to its max volume. It won't get loud enough to fill up larger or more open spaces.
This speaker has a fair battery performance. It's advertised to last around 12 hours from a single four-hour charge. However, in practice, you'll get closer to seven hours of consistent playback. On the upside, charging is faster than advertised: it took us just under three hours to reach a full charge. That said, battery performance can vary depending on your usage, so your experience may differ. There's also an 'Auto-Off Timer' power-saving feature you can program to shut the speaker off automatically following 5, 20, 40, 60, or 180 minutes of inactivity.
The Bose SoundLink Flex doesn't have any built-in voice assistants. If you want to control it with your voice, pair a smartphone with Google Assistant or Siri to the device. It doesn't struggle to hear your commands, even if you're in the middle of a noisy party or if you're further away from the speaker itself. Importantly, this feature isn't available if you purchase the SE variant of this speaker since it comes without a microphone.
The Bose Connect app is okay. It's compatible with both iOS and Android devices, and you can use it to pair the Bose SoundLink Flex to another Bose speaker to create a stereo pair. You can even link up multiple other compatible Bose speakers and soundbars when you want your audio to fill a large room. Unfortunately, unlike the Bose SoundLink Flex (2nd Gen), it lacks sound customization features like a graphic EQ and presets, so you can't tweak its sound to better suit your preferences. The Anker Soundcore Motion 300 is another similar speaker with more sound customization tools.
This speaker doesn't have any inputs. There's only a USB-C port to charge it. If you're looking for a Bose speaker with an AUX input, it's worth checking out the Bose SoundLink Mini II Special Edition. Or you can check out the Beats Pill, which can playback lossless content via a USB-C connection.
This speaker has great Bluetooth connectivity. You can pair it with up to two devices simultaneously, meaning you can switch between using your phone and laptop as an audio source in no time. Latency with iOS and Android devices is slightly high, though, so it's not ideal for streaming videos and movies as you may notice some lip-synching issues. That said, different devices and apps compensate for latency differently.