Audio review
Bose SoundLink Flex Review: Best of Fifteen, Worst on Battery
One lab ranked it second out of fifteen speakers and scored its battery 4.6 out of 10 in the same breath. Both of those are the same product working exactly as designed.
By Paulo GerchonPublished 2 min read
Illustration, not a photo — we don’t have a licensed image of this product yet.
Bose
Bose SoundLink Flex 2nd Gen
Good · researched from 3 sources
The best-sounding speaker of this size that we have found evidence for, and one of the toughest, wrapped around a battery that no source measured anywhere near the claim. Buy it for how it sounds and how much abuse it takes, and carry a charger.
- Buy if
- Pools, showers, beaches and boats, on the IP67 rating and the fact it floats · Listening at moderate volume where sound quality matters more than loudness · Anyone who wants a small speaker that survives being dropped
- Skip if
- Parties or large outdoor spaces, on the measured 88.4 dB ceiling · Long days away from power · Anyone who needs a wired input
We don’t list prices, because Amazon’s change hourly.
Two verdicts from the same test
TechGearLab put fifteen Bluetooth speakers through the same process. This one came second overall, with sound quality 7.5 and durability 9.0.
Its battery scored 4.6 out of 10.
Both results are correct and they describe the same design decision. Bose has built something small, sealed, unusually well-tuned for its size and genuinely rugged, and the space that leaves for a cell is limited.
What the battery actually does
Bose claims 12 hours. The Product Analyst points out that figure assumes 30 to 50 percent volume, which is a detail worth reading before you plan around it.
TechGearLab measured 10 hours 46 minutes under their protocol. SoundGuys held a steady 80 dB at one metre and got 7 hours 3 minutes.
Neither is wrong. Loud playback roughly halves the number, and at this speaker's size there is no way around that.
The sound is the reason to buy it
TechGearLab's summary is the strongest claim anyone makes for it: the best sounding speaker of its size that is packable and durable for outdoor use. They found the mix cohesive and controlled, with vocals unusually clear, and no distortion at maximum.
The Product Analyst praises the dynamism and instrument separation while being honest about the limits. The bass is a touch thin out of the box, and the sound compresses as you approach maximum volume, which rules it out for parties.
TechGearLab measured that maximum at 88.4 dB. That fills a bathroom or a kitchen. It does not fill a garden.
The durability was tested, not assumed
Dropped repeatedly from several feet onto hard flooring, with only cosmetic scuffs. IP67, so dust-tight and good for a metre of water for half an hour. It floats, though SoundGuys notes Bose does not want you playing music while it is floating.
One real weakness turned up: TechGearLab found sand working in behind the grille during beach use, which is the one environment where the rating does not save you.
What changed, and what did not
Bluetooth 5.3 in place of 4.2, which brings aptX and multipoint. That is the upgrade.
SoundGuys describes the sound as identical to the original and says existing owners have no reason to move. The Product Analyst agrees there is no meaningful improvement over the 2021 model.
Both also note the EQ is shallow, a three-band affair rather than anything parametric, and SoundGuys finds the buttons mushy. PositionIQ, which adjusts the tuning depending on how the speaker is sitting, produced an audible treble change in their testing but no benefit they could identify, and it cannot be switched off.
How it scored
The overall 7.3 is the weighted average of these five criteria — we never adjust it by hand.
Sound quality
TechGearLab scored sound 7.5 and called it the best sounding speaker of its size. The Product Analyst praises the dynamism and separation while finding the bass a touch thin out of the box.
Value
The Product Analyst scored 8.2 out of 10 and SoundGuys 7.4, with both noting it is barely changed from the 2021 original and priced above similarly specified rivals.
Build quality
TechGearLab scored durability 9.0 after dropping it repeatedly onto hard flooring with only cosmetic scuffs. IP67 rated, and it floats.
Ease of use
Multipoint and a shortcut button for a voice assistant or Spotify Tap. SoundGuys calls the buttons mushy and notes PositionIQ cannot be turned off.
Battery
TechGearLab scored battery 4.6 out of 10 and measured 10 hours 46 minutes. SoundGuys measured 7 hours 3 minutes at a steady 80 dB against Bose's 12 hour claim.
Pros and cons
What we liked
- TechGearLab ranked it second of fifteen speakers and scored durability 9.0
- Survived repeated drops onto hard flooring with only cosmetic scuffs
- IP67 rated, submersible to one metre for thirty minutes, and it floats
- Bluetooth 5.3 with aptX and multipoint, up from 4.2 on the original
- TechGearLab measured Bluetooth range up to 133 feet
- A shortcut button that triggers a voice assistant or Spotify Tap
What we didn’t
- SoundGuys measured 7 hours 3 minutes at 80 dB against a 12 hour claim
- TechGearLab measured maximum volume at 88.4 dB and scored volume 6.6
- The Product Analyst says the sound compresses near maximum volume
- No aux input, which both TechGearLab and SoundGuys list as a criticism
- SoundGuys finds PositionIQ of little benefit and says it cannot be disabled
- TechGearLab reports sand working in through the grille at the beach
Specifications
| Battery | 12 hours claimed; 10 h 46 m per TechGearLab; 7 h 3 m at 80 dB per SoundGuys |
|---|---|
| Maximum volume | 88.4 dB measured by TechGearLab |
| Water resistance | IP67, submersible to 1 m for 30 minutes, and it floats |
| Weight | 589 g per SoundGuys; 1.3 lb per TechGearLab |
| Dimensions | 203 x 45 x 89 mm per SoundGuys |
| Bluetooth | 5.3 with SBC, AAC and aptX; multipoint supported |
| Range | Up to 133 feet per TechGearLab |
| Materials | Aluminium, steel, silicone and nylon per The Product Analyst |
| Missing | No aux input |
How we researched this
We have not had this unit on the bench. This review synthesises the manufacturer’s published specifications, independent measurements and owner reports listed below. Every figure on this page comes from one of those sources rather than our own measurement.
3
sources reviewed
All three sources cover the second-generation Flex specifically rather than the 2021 original, which matters because the two look identical and differ mainly in Bluetooth. SoundGuys supplies the harder battery measurement, the dimensions, the codec list and the PositionIQ assessment. TechGearLab supplies the category scores, the group ranking, the measured maximum volume, the Bluetooth range and the drop testing. The Product Analyst supplies the materials, the flotation detail and the observation about compression at high volume. The two battery measurements differ by more than three hours because the test levels differ, which the FAQ sets out rather than averaging.
What we read
Common questions
How long does the Bose SoundLink Flex battery actually last?
How loud does it go?
Is it genuinely tough?
What is PositionIQ and does it help?
Should I upgrade from the first-generation Flex?
The bottom line on the Bose SoundLink Flex 2nd Gen
The best-sounding speaker of this size that we have found evidence for, and one of the toughest, wrapped around a battery that no source measured anywhere near the claim. Buy it for how it sounds and how much abuse it takes, and carry a charger.
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