Short answer: the Soundcore Boom 3i. It ranks #31 of 164 medium portable speakers against the Flex’s #38, and it costs $39 less on top of that.
Both speakers land on a similar warm, bass-forward sound, but for different reasons. The Boom 3i’s notes say it looks designed as a direct competitor to the JBL Charge 5, with a very similar sound profile that offers better value for the money, though it doesn’t quite match the Charge 5 for loudness or balance. An earlier firmware version had some bass distortion, addressed in a Soundcore App update. The Flex’s notes describe it as warm sounding with overly boosted bass that drowns out midrange detail, and it is not stereo.
The Flex counters with ruggedness. Its notes call it IP67 rated and tough enough to survive drops from several feet, and it floats, which the Boom 3i’s IP68 rating doesn’t specifically claim in its own notes. The Flex also supports Bose Party mode for multi-speaker pairing, where the Boom 3i has none.
Everything else favors the Boom 3i on paper: a longer 16 hour battery estimate against 12 hours, AAC codec support where the Flex is SBC only, and 50W of output from its 94mm woofer and tweeter.
Buy the Soundcore Boom 3i for the higher rank, lower price, and longer battery life.
Buy the Bose Soundlink Flex if you specifically want its rugged, floatable build or multi-speaker Party mode pairing.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| Soundcore Boom 3i | Bose Soundlink Flex | |
|---|---|---|
| Price | $118.99 | $79.99 |
| Ranked | #31 of 164 in Medium Size Portable Bluetooth Speakers | #38 of 164 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Aux Input | No | No |
| Bass Extension (-10dB) | 56Hz | 56Hz |
| Battery Life | 16 hours (Manufacturer specified) | 12 hours (Manufacturer specified) |
| EQ | Yes | No |
| IP Rating | IP68 | IP67 |
| Party Mode | No | Yes (Bose Party mode) |
| Power Input | USB-C | USB-C |
| Stereo | No | No |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | 4.2 |
| Dimensions | 8.3” x 3.3” x 3.1” (210 x 85 x 78.5 mm) | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) |
| Drivers | 94mm woofer + tweeter | 1x 60mm full-range driver + 2x passive radiators |
| Weight | 1.7 lbs (783 g) | 1.3 lbs (589 g) |
| Amplifier Power | 50W | - |
| Bluetooth Codecs | SBC, AAC | SBC |
| Built-in Microphone | Yes | Yes |
| Digital Aux Input | No | No |
| Lights | Yes | - |
| Strap | Yes (detachable strap) | Yes (built-in loop) |
| Bluetooth Latency | - | 33ms |
| Maximum SPL | - | 96dB (measured by Alan Ross Reviews) |
Related Speaker Comparisons
How Soundcore Boom 3i compares with other leading options:
- Soundcore Boom 3i vs Earfun Uboom L
- Soundcore Motion 300 vs Soundcore Boom 3i
- Soundcore Motion+ vs Soundcore Boom 3i
- Soundcore Boost “upgraded” 2021 vs Soundcore Boom 3i
- Soundcore Boom 3i vs Minirig 4
Prices on this page were last checked October 3, 2026 at 10:26 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
Soundcore Boom 3i: $118.99 Amazon B&H Photo Video eBay
Pros: Looks to be designed as a direct competitor to the Charge 5 with a very similar sound profile, warm tuned with boosted bass. Better value for the money than the Charge 5. Measured bass extension of 56Hz (-10dB).
Cons: Not quite as good as a Charge 5, doesn’t go quite as loud or sound quite as balanced, but very very close. An earlier firmware version had some bass distortion, update your firmware in the Soundcore App
Full Soundcore Boom 3i review and specifications →
| Amplifier Power | 50W |
|---|---|
| App | Yes |
| Aux Input | No |
| Bass Extension (-10dB) | 56Hz |
| Battery Life | 16 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC, AAC |
| Bluetooth Version | 5.3 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 8.3” x 3.3” x 3.1” (210 x 85 x 78.5 mm) |
| Drivers | 94mm woofer + tweeter |
| EQ | Yes |
| IP Rating | IP68 |
| Lights | Yes |
| Omnidirectional | No |
| Party Mode | No |
| Power Input | USB-C |
| Stereo | No |
| Strap | Yes (detachable strap) |
| TWS | Yes |
| Weight | 1.7 lbs (783 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
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Bose Soundlink Flex: $79.99 Amazon eBay
Newer model: the Bose Soundlink Flex 2nd gen, ranked higher, rated 3.8/5.
Pros: IP67 rated; rugged enough to survive drops from several feet and floats. Around 12 hours of battery at moderate volume. Measured bass extension of 56Hz (-10dB).
Cons: Not stereo. Warm sounding with overly boosted bass which drowns out midrange detail
Full Bose Soundlink Flex review and specifications →
| App | Yes |
|---|---|
| Aux Input | No |
| Bass Extension (-10dB) | 56Hz |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Latency | 33ms |
| Bluetooth Version | 4.2 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 7.9” x 3.5” x 2” (201 x 90 x 52 mm) |
| Drivers | 1x 60mm full-range driver + 2x passive radiators |
| EQ | No |
| IP Rating | IP67 |
| Maximum SPL | 96dB (measured by Alan Ross Reviews) |
| 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 (589 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Joy & Oluv’Sone: Bose Soundlink Flex 2nd gen vs Flex More from Oluv’Sone →
- Alan Ross Reviews: Bose Soundlink Flex Review! vs JBL Flip 6 and JBL Charge 5. Travel heaven?? 🤞 More from alanrossreviews →
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- Alan Ross Reviews: Tribit Xsound Mega vs the world! (JBL Charge 5, Bose Flex, Sony XB33, LG PL7) 👍
- Alan Ross Reviews: Bose Soundlink Flex vs Soundcore Boost vs Bogasing M4 - cheap or Bose?
- Alan Ross Reviews: Tribit Stormbox Flow has deeper bass than the Bose Flex but………..
- Jay’s Straight Up Reviews & More: Tribit Stormbox Flow vs Soundcore Motion 300 (LDAC) 😵 Budget Bose Soundlink Flex "Inspired" Speakers More from JaysStraightUpReviews →
- Oluv Patreon: Soundcore Motion 300 = Bose Soundlink Flex = Earfun UBoom L?
- Alan Ross Reviews: Bose Soundlink Flex or JBL Flip 6 (eq adjusted) or Denon Envaya - best speaker for travel!
- Alan Ross Reviews: Bose Soundlink Flex or Beosound A1 (1st gen) - ultimate compact speaker 😇
- Alan Ross Reviews: Bose Soundlink Flex or JBL Flip 6 (eq adjusted) or Denon Envaya - best speaker for travel!
- Jay’s Straight Up Reviews & More: Tribit Stormbox Flow vs Soundcore Motion 300 (LDAC) 😵 Budget Bose Soundlink Flex "Inspired" Speakers
- Patricio Benadon: Bose SoundLink Flex vs. Mini 2 SE. Music audio quality sound test. Listen 4 different genres!
- Patricio Benadon: Bose SoundLink Flex vs. Mini 2 SE. Music audio quality sound test. Listen 4 different genres!
- Danny Pops: BEST Bose Speaker?? Bose Soundlink Flex vs micro, Color II, and revolve + More from DannyPops →
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- Joy & Oluv’Sone: JBL, Bose, B&O, Sonos, Earfun, SoundCore… which portable speaker sounds best?
- Alan Ross - The Anti Shill!: Small speaker, mighty sound, The Flex gen 2 shatters physics!
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