Short answer: the Bose Soundlink Flex 2nd gen. It ranks #36 of 157 medium speakers by sound quality (rated 3.8/5); the Boat Stone 350 ranks #135 (rated 2.3/5).
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. It is rated higher for sound quality than the Boat Stone 350.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Bose Soundlink Flex 2nd gen | Boat Stone 350 | |
|---|---|---|
| Price | $159.00 | - |
| Ranked | #36 of 157 in Medium Size Portable Bluetooth Speakers | #135 of 157 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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Prices on this page were last checked October 2, 2026 at 10:18 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Speakers In Full
Bose Soundlink Flex 2nd gen: $159.00 Amazon eBay
Older model: the Bose Soundlink Flex (ranked lower, rated 3.8/5).
Pros: A very portable 586g, IP67-rated speaker with a clear, well-balanced midrange that keeps voices and instruments intelligible. The second generation adds a Bose app with 3-band EQ, better-placed controls and stereo pairing with another Bose Soundlink Flex 2nd gen. It supports AAC and aptX Adaptive in addition to SBC, making it a stronger wireless option than most small rivals.
Cons: 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 claimed battery life is only 12 hours, and some owners report accelerated standby drain after firmware updates. It is expensive for its size, so the added app and codec support, not a transformational sound upgrade over the original, are the main reasons to choose it.
Full Bose Soundlink Flex 2nd gen review and specifications →
| App | Yes |
|---|---|
| Aux Input | No |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC, AAC, aptX Adaptive |
| Bluetooth Version | 5.3 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) |
| Drivers | 60mm full-range driver with passive radiators |
| EQ | Yes (3 band) |
| IP Rating | IP67 |
| Omnidirectional | No |
| Party Mode | Yes (Bose Party mode) |
| Power Input | USB-C |
| Stereo | No |
| Strap | Yes (built-in loop) |
| TWS | Yes |
| Weight | 1.3 lbs (586 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Joy & Oluv’Sone: Bose Soundlink Flex 2nd gen vs Flex More from Oluv’Sone →
- Oluv Patreon: Bose Soundlink Flex 2nd gen - sound demo
- Tô Thái Trí Hùng: Unbox & Sound Test - Bose Soundlink Flex 2
- Joy & Oluv’Sone: Bose Soundlink Flex 2nd gen & Soundcore Motion 300 sound test
- Alan Ross: Hall of Fame classic vs latest Bose tech! More from alanrossreviews →
- CEONTHEMAKING: Bose Soundlink Flex 2nd Gen VS Marshall Emberton III - What’s NEW?? More from CEONTHEMAKING →
- Alan Ross - The Anti Shill!: Small speaker, mighty sound, The Flex gen 2 shatters physics!
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Boat Stone 350 eBay
Pros: 10W cylindrical stereo speaker with dual passive radiators, IPX7 water resistance, microSD card slot, and 3.5mm aux input. Measured bass extension of 87Hz (-10dB).
Cons: Midrange peaks with rolled-off treble. Bass extension limited below 87Hz.
Full Boat Stone 350 review and specifications →
| Amplifier Power | 10W |
|---|---|
| App | No |
| Aux Input | Yes |
| Bass Extension (-10dB) | 87Hz |
| Battery Life | 6 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) |
| Bluetooth Version | 5.0 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 3.5” x 7.1” (90 x 180 mm) |
| Drivers | 2x 20mm tweeters + 2x 45mm drivers |
| EQ | Yes (multiple modes) |
| IP Rating | IPX7 |
| MicroSD Playback | Yes |
| Omnidirectional | No |
| Power Input | USB-C |
| Stereo | Yes |
| Strap | No |
| TWS | Yes |
| Weight | 0.9 lbs (426 g) |
- Links
- Reviews, Comparisons and Sound Samples
- No independent measurement review is linked for this model; it is ranked from hands-on listening and comparison against similarly priced speakers.
- Head-to-Head Comparisons
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