These sit in different size classes, so this is not a straight ranking comparison. The Bose Soundlink Flex 2nd gen ranks #35 of 144 medium speakers by sound quality at $159; the Marshall Stockwell III ranks #59 of 82 large speakers by sound quality at $249.99.
What the Bose Soundlink Flex 2nd gen does well: A very portable 586g, IP67-rated speaker with a clear, well-balanced midrange that keeps voices and instruments intelligible. The catch: 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.
Why pick the Marshall Stockwell III: 40+ hour battery life with a user-replaceable battery, strap, sleeve and grilles. Watch for: Highs are recessed by default and need the treble control maxed to compensate, still lacking detail even then.
Buy the Bose Soundlink Flex 2nd gen at $159 for a medium speaker, or the Marshall Stockwell III at $249.99 for a large speaker instead.
If battery life is a priority, the Marshall Stockwell III is rated for 40 hours versus 12 hours for the Bose Soundlink Flex 2nd gen.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
Specifications Side By Side
| Bose Soundlink Flex 2nd gen | Marshall Stockwell III | |
|---|---|---|
| Price | $159.00 | $249.99 |
| Ranked | #35 of 144 in Medium Size Portable Bluetooth Speakers | #59 of 82 in Large Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Battery Life | 12 hours (Manufacturer specified) | 40+ hours (Manufacturer specified) |
| Built-in Microphone | Yes | - |
| EQ | Yes (3 band) | Yes (parametric, via app) |
| IP Rating | IP67 | IP55 |
| Party Mode | Yes (Bose Party mode) | - |
| Power Input | USB-C | USB-C |
| Stereo | No | Partially |
| Omnidirectional | No | Yes |
| TWS | Yes | No |
| Weight | 1.3 lbs (586 g) | 2.9 lbs (1.3 kg) |
| Bluetooth Version | 5.3 | 5.3 |
| Dimensions | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) | 7.1” x 6.4” x 2.9” (180 x 162 x 74 mm) |
| Aux Input | No | Yes |
| Drivers | 60mm full-range driver with passive radiators | 1x 3” woofer, 2x 1.75” wide-band drivers |
| Bluetooth Codecs | SBC, AAC, aptX Adaptive | SBC, AAC, LE Audio with LC3 |
| Digital Aux Input | No | No |
| Strap | Yes (built-in loop) | Yes (detachable strap) |
| Frequency Response | - | 54Hz - 20kHz (Manufacturer specified) |
| Amplifier Power | - | 44W |
| Power Bank | - | Yes |
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Prices on this page were last checked September 26, 2026 at 11:14 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 (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 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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Marshall Stockwell III: $249.99 Marshall eBay
Older model: the Marshall Stockwell II (rated 4.5/5).
Pros: 40+ hour battery life with a user-replaceable battery, strap, sleeve and grilles. Doubles as a USB-C power bank. IP55 dust/water resistance. App includes parametric EQ, a Soundstage widening control, and wall/corner placement compensation. Endless-rotation control knobs.
Cons: Highs are recessed by default and need the treble control maxed to compensate, still lacking detail even then. Bass tends to sound resonant and boomy, with reported frequency cancellation and phase issues on complex material that EQ doesn’t fully resolve. Oluv’s A/B testing against the outgoing Stockwell II finds the default tuning muffled and muddy enough to prefer the seven-year-old original out of the box, and output loses dynamics and bass while turning harsh well below maximum volume. No aptX support.
Full Marshall Stockwell III review and specifications →
| Amplifier Power | 44W |
|---|---|
| App | Yes |
| Aux Input | Yes |
| Battery Life | 40+ hours (Manufacturer specified) |
| Bluetooth Codecs | SBC, AAC, LE Audio with LC3 |
| Bluetooth Version | 5.3 |
| Digital Aux Input | No |
| Dimensions | 7.1” x 6.4” x 2.9” (180 x 162 x 74 mm) |
| Drivers | 1x 3” woofer, 2x 1.75” wide-band drivers |
| EQ | Yes (parametric, via app) |
| Frequency Response | 54Hz - 20kHz (Manufacturer specified) |
| IP Rating | IP55 |
| Omnidirectional | Yes |
| Power Bank | Yes |
| Power Input | USB-C |
| Stereo | Partially |
| Strap | Yes (detachable strap) |
| TWS | No |
| Weight | 2.9 lbs (1.3 kg) |
- Links
- Reviews, Comparisons and Sound Samples
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