Short answer: the Bose Soundlink Flex 2nd gen on measured sound quality, the Boat Stone 350 on price. The Bose Soundlink Flex 2nd gen ranks #37 of 172 medium speakers, rated 3.8/5, at $159. The Boat Stone 350 ranks #149, rated 2.3/5, at $18, $141 cheaper.
The Bose Soundlink Flex 2nd gen is the better-sounding, longer-running option. A very portable 1.3 lbs (586 g), IP67-rated speaker with a clear, well-balanced midrange that keeps voices and instruments intelligible. It is rated for 12 hours of battery against 6 for the Boat Stone 350. Watch for: One Flex remains mono and cannot deliver genuine low-bass rumble; RTINGS also found the elevated treble can turn hi-hats and other high-frequency detail piercing.
The Boat Stone 350 is the lighter pick. 10W cylindrical stereo speaker with dual passive radiators, IPX7 water resistance, microSD card slot, and 3.5mm aux input. At 0.9 lbs (426 g) it weighs noticeably less than the Bose Soundlink Flex 2nd gen at 1.3 lbs (586 g). It keeps a wired aux input, which the Bose Soundlink Flex 2nd gen lacks. It plays in stereo from a single unit, unlike the Bose Soundlink Flex 2nd gen. The tradeoff: Midrange peaks with rolled-off treble.
Buy the Bose Soundlink Flex 2nd gen when sound quality outweighs the price for you, and the Boat Stone 350 when the price outweighs sound quality instead.
Looking for alternatives? See the complete Portable Bluetooth rankings.
A very portable 586g, IP67-rated speaker with a clear, well-balanced midrange that keeps voices and instruments intelligible.
Amazon $159.00 eBay
10W cylindrical stereo speaker with dual passive radiators, IPX7 water resistance, microSD card slot, and 3.5mm aux input.
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Specifications Side By Side
| Bose Soundlink Flex 2nd gen | Boat Stone 350 | |
|---|---|---|
| Price | $159.00 | $18 |
| Ranked | #37 of 172 in Medium Size Portable Bluetooth Speakers | #149 of 172 in Medium Size Portable Bluetooth Speakers |
| App | Yes | No |
| Battery Life | 12 hours (Manufacturer specified) | 6 hours (Manufacturer specified) |
| Built-in Microphone | Yes | Yes |
| EQ | Yes (3 band) | Yes (multiple modes) |
| IP Rating | IP67 | IPX7 |
| Party Mode | Yes (Bose Party mode) | - |
| Power Input | USB-C | USB-C |
| Stereo | No | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 1.3 lbs (586 g) | 0.9 lbs (426 g) |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | 5.0 |
| Dimensions | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) | 3.5” x 7.1” (90 x 180 mm) |
| Aux Input | No | Yes |
| Drivers | 60mm full-range driver with passive radiators | 2x 20mm tweeters + 2x 45mm drivers |
| Bluetooth Codecs | SBC, AAC, aptX Adaptive | SBC (inferred; additional codecs unverified) |
| Digital Aux Input | No | No |
| Strap | Yes (built-in loop) | No |
| Bass Extension (-10dB) | - | 87Hz |
| MicroSD Playback | - | Yes |
| Amplifier Power | - | 10W |
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