Short answer: the Bose Soundlink Flex 2nd gen. It ranks #37 of 175 medium speakers by sound quality, rated 3.8/5, at $99.99. The Ultimate Ears Wonderboom 2 ranks #111, rated 2.9/5, at $80, $19.99 cheaper, a saving that is not big enough to make up the sound-quality gap.
The Bose Soundlink Flex 2nd gen is the better-sounding 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 supports aptX Adaptive Bluetooth, which the Ultimate Ears Wonderboom 2 lacks. It links with other speakers (Bose Party mode), which the Ultimate Ears Wonderboom 2 cannot. It has an adjustable EQ, which the Ultimate Ears Wonderboom 2 lacks. The tradeoff: 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 Ultimate Ears Wonderboom 2 is the lighter choice. IP67 rated and floats. At 0.9 lbs (420 g) it weighs noticeably less than the Bose Soundlink Flex 2nd gen at 1.3 lbs (586 g). Watch for: Not stereo, barely any bass, recessed treble.
Buy the Bose Soundlink Flex 2nd gen. It is rated higher for sound quality, and the $19.99 saving on the Ultimate Ears Wonderboom 2 is not enough to make up the difference.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Bose Soundlink Flex 2nd gen | Ultimate Ears Wonderboom 2 | |
|---|---|---|
| Price | $99.99 | $80 |
| Ranked | #37 of 175 in Medium Size Portable Bluetooth Speakers | #111 of 175 in Medium Size Portable Bluetooth Speakers |
| App | Yes | No |
| Battery Life | 12 hours (Manufacturer specified) | 12 hours (Manufacturer specified) |
| Built-in Microphone | Yes | No |
| EQ | Yes (3 band) | No |
| IP Rating | IP67 | IP67 |
| Party Mode | Yes (Bose Party mode) | No |
| Power Input | USB-C | Micro USB |
| Stereo | No | No |
| Omnidirectional | No | Yes |
| TWS | Yes | Yes |
| Weight | 1.3 lbs (586 g) | 0.9 lbs (420 g) |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | 5.1 |
| Dimensions | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) | 4.1” x 3.8” (104 x 95.3 mm) |
| Aux Input | No | No |
| Drivers | 60mm full-range driver with passive radiators | 2x 40mm active drivers + 2x passive radiators |
| Bluetooth Codecs | SBC, AAC, aptX Adaptive | SBC |
| Digital Aux Input | No | No |
| Strap | Yes (built-in loop) | Yes (built-in loop) |
| Bass Extension (-10dB) | - | 82Hz |
| Maximum SPL | - | 88dB (measured by Alan Ross Reviews) |
Related Speaker Comparisons
More worthwhile head-to-heads for Bose Soundlink Flex 2nd gen:
- Bose Soundlink Flex 2nd gen vs EarFun Uboom L
- Bose Soundlink Flex 2nd gen vs Soundcore Motion 300
- Bose Soundlink Flex 2nd gen vs Soundcore Motion+
- Bose Soundlink Flex 2nd gen vs Soundcore Boost “upgraded” 2021
- Bose Soundlink Flex 2nd gen vs Minirig 4
Prices on this page were last checked October 12, 2026 at 4:13 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: $99.99 Amazon $99.99 eBay
Older model: the Bose Soundlink Flex (ranked lower, rated 3.8/5). See every Bose SoundLink Flex, Micro, Max and Plus generation.
Same family: the Bose SoundLink Max (larger model, rated 4.3/5), the Bose Soundlink Micro 2 (larger model, rated 3.6/5) and the Bose SoundLink Plus (larger model, rated 4.2/5).
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 →
| Released | Sep 2024 (2 years ago) |
|---|---|
| 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 →
- Joy & Oluv’Sone: Bose Soundlink Flex 2nd gen & Soundcore Motion 300 sound test
- Oluv Patreon: Bose Soundlink Flex 2nd gen - sound demo
- Alan Ross: Hall of Fame classic vs latest Bose tech! More from alanrossreviews →
- Alan Ross - The Anti Shill!: Small speaker, mighty sound, The Flex gen 2 shatters physics!
- Alan Ross - The Anti Shill!: DBSONO X-Blast F37 vs Bose Soundlink Flex 2 - They all want to be me 😊
- Mateusz Cholewa: JBL Charge Essential 3 SE vs BOSE SoundLink FLEX 2 More from Mateusz Cholewa →
- CEONTHEMAKING: Bose Soundlink Flex 2nd Gen VS Marshall Emberton III - What’s NEW?? More from CEONTHEMAKING →
- Tô Thái Trí Hùng: Unbox & Sound Test - Bose Soundlink Flex 2
- Musou1: JBL flip 7 vs KEF muo vs Bose flex 2
- Head-to-Head Comparisons
- Bose Soundlink Flex 2nd gen vs Bose Soundlink Flex
- Bose Soundlink Flex 2nd gen vs Tribit Xsound Plus 2
- Bose Soundlink Flex 2nd gen vs JBL Charge Essential 2
- Bose Soundlink Flex 2nd gen vs Teufel Rockster XS
- Bose Soundlink Flex 2nd gen vs Huawei Sound Joy
- Bose Soundlink Flex 2nd gen vs Cleer Audio Scene
- Bose Soundlink Flex 2nd gen vs Soundcore Boom 3i
- Bose Soundlink Flex 2nd gen vs JBL Charge Essential 3 SE
- See all 146 comparisons
Ultimate Ears Wonderboom 2: $80 Amazon $80 eBay
Newer model: the Ultimate Ears Wonderboom 4, ranked higher, rated 2.9/5, released Jun 2024.
Older model: the Ultimate Ears Wonderboom (ranked lower, rated 2.9/5). See every Ultimate Ears Wonderboom, Boom and Megaboom generation.
Pros: IP67 rated and floats. Compact and light enough to toss in a bag. Measured bass extension of 82Hz (-10dB).
Cons: Not stereo, barely any bass, recessed treble. Slightly boosted 93Hz upper bass Dip at 9kHz. You can tell from the micro USB that they are just feeding you the same crap hardware over and over, this is inexcusable for a product released in 2019. Not technically a 360 speaker, only front and rear.
Full Ultimate Ears Wonderboom 2 review and specifications →
| Released | Jun 2019 (7 years ago) |
|---|---|
| App | No |
| Aux Input | No |
| Bass Extension (-10dB) | 82Hz |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.1 |
| Built-in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 4.1” x 3.8” (104 x 95.3 mm) |
| Drivers | 2x 40mm active drivers + 2x passive radiators |
| EQ | No |
| IP Rating | IP67 |
| Maximum SPL | 88dB (measured by Alan Ross Reviews) |
| Omnidirectional | Yes |
| Party Mode | No |
| Power Input | Micro USB |
| Stereo | No |
| Strap | Yes (built-in loop) |
| TWS | Yes |
| Weight | 0.9 lbs (420 g) |
- Reviews, Comparisons and Sound Samples
- Alan Ross Reviews: The biggest upgrade since time began! 💪 More from alanrossreviews →
- Alan Ross Reviews: UE Wonderboom 2 review and sound test - vs Flip 5 - Flip 4
- Alan Ross Reviews: Soundcore Flare 2 - mega 360 degree speaker shootout!
- Danny Pops: MICRO SPEAKERS - my take on JBL Clip 4 VS Wonderboom 2 VS Bose Micro More from DannyPops →
- Head-to-Head Comparisons
- Ultimate Ears Wonderboom 2 vs Ultimate Ears Wonderboom 3
- Ultimate Ears Wonderboom 2 vs Ultimate Ears Wonderboom
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- Ultimate Ears Wonderboom 2 vs Ultimate Ears Wonderboom 4
- Ultimate Ears Wonderboom 2 vs Ultimate Ears Boom 3
- Ultimate Ears Wonderboom 2 vs Ultimate Ears Megaboom 3
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- See all 89 comparisons