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 and is still sold new; the Sony XB33 ranks #77 (rated 3.4/5) and is discontinued, so it is only an option used. The Sony XB33’s replacement, the Sony ULT Field 3, is rated 3.4/5 at $208.
The Bose Soundlink Flex 2nd gen is the better-sounding, lighter option. A very portable 1.3 lbs (586 g), IP67-rated speaker with a clear, well-balanced midrange that keeps voices and instruments intelligible. At 1.3 lbs (586 g) it weighs much less than the Sony XB33 at 2.4 lbs (1.1 kg). 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 Sony XB33 is the longer-running choice. IP67 rated and lightweight (2.4 lb). It is rated for 24 hours of battery against 12 for the Bose Soundlink Flex 2nd gen. It supports LDAC Bluetooth, which the Bose Soundlink Flex 2nd gen lacks. It plays in stereo from a single unit, unlike the Bose Soundlink Flex 2nd gen. Watch for: Not very loud.
Buy the Bose Soundlink Flex 2nd gen. It is rated higher for sound quality, and the Sony XB33 is discontinued, so it is only available used.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
Specifications Side By Side
| Bose Soundlink Flex 2nd gen | Sony XB33 | |
|---|---|---|
| Price | $99.99 | $110 Discontinued |
| Ranked | #37 of 175 in Medium Size Portable Bluetooth Speakers | #77 of 175 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes (Sony Music Connect App) |
| Battery Life | 12 hours (Manufacturer specified) | 24 hours (Manufacturer specified) |
| Built-in Microphone | Yes | - |
| EQ | Yes (3 band) | Yes (3 band) |
| IP Rating | IP67 | IP67 |
| Party Mode | Yes (Bose Party mode) | Yes (Party Connect up to 100 speakers) |
| Power Input | USB-C | USB-C |
| Stereo | No | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 1.3 lbs (586 g) | 2.4 lbs (1.1 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | 5.0 |
| Dimensions | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) | 9.7” x 3.8” x 4.2” (246 x 97 x 106 mm) |
| Aux Input | No | No |
| Drivers | 60mm full-range driver with passive radiators | 2x 48x70mm X-Balanced racetrack drivers + 2x passive radiators |
| Bluetooth Codecs | SBC, AAC, aptX Adaptive | SBC, AAC, LDAC |
| Digital Aux Input | No | No |
| Strap | Yes (built-in loop) | - |
| Bass Extension (-10dB) | - | 50Hz |
| Bluetooth Latency | - | 110ms |
| Maximum SPL | - | 97dB (measured by Alan Ross Reviews) |
| Power Bank | - | Yes (USB-A) |
| Amplifier Power | - | 16W RMS |
| Lights | - | Yes |
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
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- 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
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- See all 146 comparisons
Sony XB33: $110 Discontinued eBay
Newer model: the Sony ULT Field 3, ranked higher, rated 3.4/5, released Apr 2025.
Older models: the Sony SRS-XB31 (ranked lower, rated 2.8/5) and the Sony SRS-XB30 (ranked lower, rated 2.6/5). See every Sony XB and ULT generation.
Pros: IP67 rated and lightweight (2.4 lb). App-controlled color LED lighting, Party Connect links up to 100 speakers. ~19 hour real-world battery without lights. Measured bass extension of 50Hz (-10dB).
Cons: Not very loud. Upper bass peaks, midrange dip, upper midrange peaks, not very neutral. Speaker will not remain at max volume and will turn itself down automatically. Discontinued.
Full Sony XB33 review and specifications →
| Released | May 2020 (6 years ago) |
|---|---|
| Amplifier Power | 16W RMS |
| App | Yes (Sony Music Connect App) |
| Aux Input | No |
| Bass Extension (-10dB) | 50Hz |
| Battery Life | 24 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC, AAC, LDAC |
| Bluetooth Latency | 110ms |
| Bluetooth Version | 5.0 |
| Digital Aux Input | No |
| Dimensions | 9.7” x 3.8” x 4.2” (246 x 97 x 106 mm) |
| Drivers | 2x 48x70mm X-Balanced racetrack drivers + 2x passive radiators |
| EQ | Yes (3 band) |
| IP Rating | IP67 |
| Lights | Yes |
| Maximum SPL | 97dB (measured by Alan Ross Reviews) |
| Omnidirectional | No |
| Party Mode | Yes (Party Connect up to 100 speakers) |
| Power Bank | Yes (USB-A) |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| Weight | 2.4 lbs (1.1 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Alan Ross Reviews: Sony XB33 vs XB32 vs JBL Charge 4 best £120 bluetooth speaker? More from alanrossreviews →
- Alan Ross Reviews: Sony XB23 vs XB33 - specs and measurements
- Alan Ross Reviews: Sony xb33 vs xb43 vs Soundcore Motion Plus speakers test
- Alan Ross Reviews: JBL Charge 5 vs Motion Plus and Sony XB33 - ultimate travel speaker 2021 🤗
- Alan Ross Reviews: LG Xboom Go PL7 vs JBL Charge 4 and Sony XB33 - best Bluetooth speaker?
- Alan Ross Reviews: Tribit Xsound Mega vs the world! (JBL Charge 5, Bose Flex, Sony XB33, LG PL7) 👍
- GYMCADDY: Sony XE300 Review And Compared to Sony XB33 - A Muffled Mess More from GYMCADDY →
- Head-to-Head Comparisons