Short answer: the Bose Soundlink Flex 2nd gen on measured sound quality, the Ultimate Ears Boom 3 on price. The Bose Soundlink Flex 2nd gen ranks #33 of 136 medium speakers at $159. The Ultimate Ears Boom 3 ranks #89 at $129.90, $29.10 cheaper.
What the Bose Soundlink Flex 2nd gen offers: Pretty much identical sounding to the 1st gen Watch for: Not stereo. Warm sounding with overly boosted bass which drowns out midrange detail. Self drains the battery about 10% a week.
What the Ultimate Ears Boom 3 offers: Rich and warm bass without muddying mix, crisp highs, excellent 15-hour battery life, stable Bluetooth connectivity, IP67 rated and floats, rugged fabric shell, can pair up to 150 speakers via PartyUp Watch for: Not stereo, barely any bass, recessed treble. 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 2021. Lots of mentions of failing batteries on amazon. Not technically a 360 speaker, only front and rear.
Buy the Bose Soundlink Flex 2nd gen if sound quality matters more than the price. Buy the Ultimate Ears Boom 3 if the price matters more than sound quality.
Specifications Side By Side
| Bose Soundlink Flex 2nd gen | Ultimate Ears Boom 3 | |
|---|---|---|
| Price | $159.00 | $129.90 |
| Ranked | #33 of 136 in Medium Size Portable Bluetooth Speakers | #89 of 136 in Medium Size Portable Bluetooth Speakers |
| App | Yes | - |
| Battery Life | 12 hours (Manufacturer specified) | 15 hours (Manufacturer specified) |
| Built in Microphone | Yes | No |
| EQ | Yes (3 band) | Yes (via app) |
| IP Rating | IP67 | IP67 |
| Party Mode | Yes (Bose Party mode) | Yes (PartyUp up to 50 speakers) |
| Power Input | USB-C | Micro USB |
| Stereo | No | Yes |
| Omnidirectional | No | Yes |
| TWS | Yes | Yes |
| Weight | 1.3 lbs / 586 g | 1.3 lbs / 608 g |
| Bluetooth Version | 5.3 | 4.2 |
| Dimensions | 7.9" x 3.5" x 2" (201 x 90 x 52 mm) | 7.2" x 2.9" (184 x 73 mm) |
| Aux Input | No | - |
| Drivers | 60mm full-range driver with passive radiators | 2x 2" active drivers + 2x 2" x 4" passive radiators |
| Bluetooth Codecs | SBC, AAC, aptX Adaptive | - |
| Digital Aux Input | No | No |
| Bass Extension (-10dB) | - | 91Hz |
| Max Volume | - | 87dB |
Related Speaker Comparisons
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- JBL Charge 6 vs Klipsch Groove/Heritage Groove
- Bose Soundlink Mini 2 vs Ultimate Ears Boom 4
- Klipsch Groove/Heritage Groove vs Harman Kardon Esquire 2
- Bose Soundlink Flex 2nd gen vs JBL Flip 7
- Bose Soundlink Flex 2nd gen vs Harman Kardon Citation 200
Prices on this page were last checked August 27, 2026 at 10:09 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
Pros: Pretty much identical sounding to the 1st gen
Cons: Not stereo. Warm sounding with overly boosted bass which drowns out midrange detail. Self drains the battery about 10% a week.
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 |
| 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??
- Alan Ross - The Anti Shill!: Small speaker, mighty sound, The Flex gen 2 shatters physics!
- Reddit Search for Bose Soundlink Flex 2nd gen Review
- Head-to-Head Comparisons
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- Bose Soundlink Flex 2nd gen vs Teufel Rockster XS
- Bose Soundlink Flex 2nd gen vs Soundcore Boom 3i
- Bose Soundlink Flex 2nd gen vs Soundcore Motion 100
- Bose Soundlink Flex 2nd gen vs JBL Charge 5
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Ultimate Ears Boom 3: $129.90 Amazon eBay
Pros: Rich and warm bass without muddying mix, crisp highs, excellent 15-hour battery life, stable Bluetooth connectivity, IP67 rated and floats, rugged fabric shell, can pair up to 150 speakers via PartyUp
Cons: Not stereo, barely any bass, recessed treble. 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 2021. Lots of mentions of failing batteries on amazon. Not technically a 360 speaker, only front and rear.
Full Ultimate Ears Boom 3 review and specifications →
| Bass Extension (-10dB) | 91Hz |
|---|---|
| Battery Life | 15 hours (Manufacturer specified) |
| Bluetooth Version | 4.2 |
| Built in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 7.2" x 2.9" (184 x 73 mm) |
| Drivers | 2x 2" active drivers + 2x 2" x 4" passive radiators |
| EQ | Yes (via app) |
| IP Rating | IP67 |
| Max Volume | 87dB |
| Omnidirectional | Yes |
| Party Mode | Yes (PartyUp up to 50 speakers) |
| Power Input | Micro USB |
| Stereo | Yes |
| TWS | Yes |
| Weight | 1.3 lbs / 608 g |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Ultimate Ears Boom 3 vs Ultimate Ears Boom 4
- Ultimate Ears Boom 3 vs Klipsch Groove/Heritage Groove
- Ultimate Ears Boom 3 vs Ultimate Ears Wonderboom
- Ultimate Ears Boom 3 vs Sony SRS-XE300
- Ultimate Ears Boom 3 vs Ultimate Ears Wonderboom 2
- Ultimate Ears Boom 3 vs Ultimate Ears Wonderboom 3
- Ultimate Ears Boom 3 vs Tribit Stormbox
- Ultimate Ears Boom 3 vs Sony SRS-XB20
- See all 77 comparisons