Bose SoundLink Flex review: Bluetooth speaker of the year?

I currently don’t have lots of Bluetooth speakers in my life, but that may be about to change.

I’m not super adventurous and am most often in spaces where wireless earbuds and headphones are most appropriate. At home, I’ve slowly built a Sonos-based audio system, with a HomePod mini in my bedroom to round everything out.

But there are times when I miss the convenience of a portable Bluetooth speaker. It’s nice to have something you can carry around with you from shower to the dresser to the kitchen in the morning. A lightweight but loudspeaker that can easily come with you to the pool is also hard to beat. This is how I’ve been enjoying my time with Bose’s latest Bluetooth speaker, the $150 Bose SoundLink Flex.

After weeks of testing against both my Sonos system and some competitors, this is the first speaker in a long time to tempt me to reintroduce at least one Bluetooth speaker to my life.

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Little tank

The SoundLink Flex is rated for IP67 water resistance which covers both water and dust. Even better, it floats if it’s dropped in a pool (though it does not sound good when it’s wet since most of the speaker stays submerged in the water). Bose also says the speaker should do fine if it takes a tumble but I did not want to put that to the test with my review unit.

I really like the boxy design of the SoundLink Flex, standing out from the cylindrical designs that Bluetooth speakers have stuck to for years. In the hand, it feels like a well-packed clutch bag. I’m not the biggest fan of the “White Smoke” color that Bose sent but the “Black” and “Stone Blue” colors are pretty appealing. The front grill takes up most of the speaker’s face while the rear has a thinner vent for both airflow and to aid the transducer’s output.

Battery life is rated at 12 hours by Bose. I did find the percentages to drop rather quickly after a few hours of use. It’s definitely the worst thing about the speaker as many competitors have longer battery ratings. However, driving components this loud is sure to cause more drainage than usual.

One thing that’s easy to take advantage of on Bluetooth speakers are buttons, and the SoundLink Flex’s buttons have me conflicted. They’re all very easy to press and quite responsive, but every button is under the speaker’s soft-touch materia on the rim. This makes you think you need to depress the buttons much deeper than you actually do. In actuality, a slight press does the trick. These buttons don’t feel the best but at least they work.

My favorite button is definitely the power button. Bose isn’t using any stupid “press and hold” functions for power. You press and the speaker is immediately on and paired to your phone. Press again and it’s off. It’s the simple things that delight when done right.

One smart feature

The killer feature of the SoundLink Flex is new tech Bose calls “PositionIQ”. Inside the speaker, Bose is highlighting a new transducer that’s responsible for the low end. From my testing, this is also where PositionIQ makes the biggest difference.

You hear it best whenever the SoundLink Flex is in motion or is put down somewhere while you’re playing music. Every time you change the speaker’s position the presence of the bass shifts ever so slightly. When the speaker is sitting upon a table, bass radiates from the front and back fairly evenly. Then, when you sit the speaker on its back, the low end starts to emit upwards out the front grill with little coming from the rear vent to avoid shaking the table.

In practical use, this means the speaker can act as both a 360-degree speaker or a proper directional speaker, depending on what you need. For a party, or when you’re walking around the room yourself you’ll want the speaker on its back to fill the room evenly. When listening by yourself in one place I find it best to have the SoundLink Flex facing upright.

PositionIQ is really the only “smart” aspect about the speaker but it’s in service of hardware that knocks it out of the park at this price point.

Knockout sound

As neat as PositionIQ is, it would be useless if the SoundLink Flex didn’t sound good, and thankfully it does. The SoundLink Flex not only shines at filling the room with music at high volumes without becoming distorted, but it manages to overcome many of the quality issues that face Bluetooth speakers compared to Wi-Fi-based speakers like my Sonos One SL. I’d still take my Sonos if I could only pick one, but a Bluetooth speaker of this size getting that close to it is impressive enough.

It also shines outside, getting plenty loud to pair with your pool parties and cookouts in the summer.

The bass is the real stunner here.

While PositionIQ does sound its worst when the speaker is actively in motion, I don’t count that as a downside. I doubt those going on hikes with a speaker actively playing music on their backs are listening for the delicate strums of a guitar as they walk. What is important is the speaker sounding great without the aid of walls to bounce sound off when you walk, and the SoundLink Flex achieves this handily.

The bass is the real stunner here and I can see why Bose highlights it in its press materials. While it does work best inside, in every place I tested the SoundLink Flex the bass felt very present without ever being overwhelming. There are lots of larger speakers out there that best the SoundLink Flex in audio performance but Bose has done one of the best jobs I’ve ever seen in this size category.

Bar raised

When I consider the performance on offer here, plus a design that I believe is prettier than the never-ending stream of cylindrical speakers out there, Bose has put together one hell of a package.

The SoundLink Flex’s price is also very competitive. It’s priced the same as Ultimate Ears’ popular Boom 3, while sounding better, and is $50 less than the Megaboom 3 with a sound profile I’d call a tossup. When you consider JBL’s speakers, the Flip 5 and Charge 5, Bose is sitting right between those price points of $130 and $180, respectively. These are all speakers I’ve had experience with in various capacities, whether at friends’ houses or from owning them myself in years past. I’d take the SoundLink Flex over all of them. It strikes the best balance of portability, durability, and sound quality. This is my new gold standard for Bluetooth speakers going forward.

This is my new gold standard for Bluetooth speakers going forward.

As a Sonos owner, however, I am having a harder time making the call between the SoundLink Flex and the Sonos Roam, which has more smart features, and always-on TruePlay which should offer similar if not better results than PositionIQ. The Roam is more expensive at $180 but the advantages of the Sonos ecosystem (plus higher quality audio over Wi-Fi) make the price premium easier to justify.

If all you want is a dedicated Bluetooth speaker, the SoundLink Flex is going to fit the most use cases the best, even as a stationary speaker. Consider it an easy buy this holiday season.