Short answer: the Ultimate Ears Boom 4, though neither ranks well in its class. It ranks #110 of 164 medium speakers by sound quality (rated 2.9/5) at $149.99 and is still sold new; the Soundcore Flare 2 ranks #128 (rated 2.6/5) and is discontinued, so it is only an option used. Both are rated below 3.0/5 among the 164 medium speakers, so if sound quality matters, consider the Earfun Uboom L instead, ranked #2 at $49.79.
Buy the Ultimate Ears Boom 4. It is rated higher for sound quality, and the Soundcore Flare 2 is discontinued, so it is only available used.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Soundcore Flare 2 | Ultimate Ears Boom 4 | |
|---|---|---|
| Price | $80 Discontinued | $149.99 |
| Ranked | #128 of 164 in Medium Size Portable Bluetooth Speakers | #110 of 164 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Bass Extension (-10dB) | 56Hz | - |
| Battery Life | 12 hours (Manufacturer specified) | 15 hours (Manufacturer specified) |
| EQ | Yes | Yes (via app) |
| Bluetooth Latency | 80ms | - |
| Maximum SPL | 99dB (measured by Alan Ross Reviews) | 85dBC (Manufacturer specified) |
| Party Mode | Yes (PartyCast up to 100 speakers) | - |
| Weight | 1.3 lbs (600 g) | 1.4 lbs (620 g) |
| IP Rating | IPX7 | IP67 |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.0 | 5.1 |
| Bluetooth Codecs | SBC | SBC |
| Drivers | 2x full-range drivers + 2x passive radiators | 2x 1.57” (40mm) active drivers + 2x 1.81” x 2.57” (46.1 x 65.2mm) passive radiators |
| TWS | Yes | Yes |
| Built-in Microphone | Yes | No |
| Stereo | Yes | Yes |
| Omnidirectional | Pointing up | No |
| Power Input | USB-C | USB-C |
| Amplifier Power | 20W | - |
| Digital Aux Input | No | No |
| Lights | Yes | - |
| Dimensions | 3.5” x 3.5” x 6.3” (89 x 89 x 160 mm) | 7.2” x 2.9” x 2.9” (184 x 73 x 73 mm) |
| Aux Input | No | No |
| Power Bank | - | No |
| Strap | - | Yes (built-in loop) |
Related Speaker Comparisons
How Ultimate Ears Boom 4 compares with other leading options:
- Ultimate Ears Boom 4 vs Earfun Uboom L
- Soundcore Motion 300 vs Ultimate Ears Boom 4
- Soundcore Motion+ vs Ultimate Ears Boom 4
- Soundcore Boost “upgraded” 2021 vs Ultimate Ears Boom 4
- Ultimate Ears Boom 4 vs Minirig 4
Prices on this page were last checked October 4, 2026 at 9:58 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 Flare 2: $80 Discontinued eBay
Pros: Try Alan Ross’s EQ for it. Measured bass extension of 56Hz (-10dB).
Cons: Rolled off treble. Thuddy bass. Not technically a 360 speaker, only front and rear. Discontinued and no longer sold new.
Full Soundcore Flare 2 review and specifications →
| Amplifier Power | 20W |
|---|---|
| App | Yes |
| Aux Input | No |
| Bass Extension (-10dB) | 56Hz |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Latency | 80ms |
| Bluetooth Version | 5.0 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 3.5” x 3.5” x 6.3” (89 x 89 x 160 mm) |
| Drivers | 2x full-range drivers + 2x passive radiators |
| EQ | Yes |
| IP Rating | IPX7 |
| Lights | Yes |
| Maximum SPL | 99dB (measured by Alan Ross Reviews) |
| Omnidirectional | Pointing up |
| Party Mode | Yes (PartyCast up to 100 speakers) |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| Weight | 1.3 lbs (600 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Soundcore Flare 2 vs Sony SRS-XB30
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Ultimate Ears Boom 4: $149.99 Amazon eBay
Older model: the Ultimate Ears Boom 3 (ranked lower, rated 2.9/5).
Pros: IP67 rated, floats, and finally charges via USB-C instead of the older Booms’ Micro-USB. 15 hour battery. Customizable EQ and speaker-pairing via the UE app.
Cons: Not much improvement over the old ones. Weak bass extension and thuddy bass. Gets distorted above 90%
Full Ultimate Ears Boom 4 review and specifications →
| App | Yes |
|---|---|
| Aux Input | No |
| Battery Life | 15 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.1 |
| Built-in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 7.2” x 2.9” x 2.9” (184 x 73 x 73 mm) |
| Drivers | 2x 1.57” (40mm) active drivers + 2x 1.81” x 2.57” (46.1 x 65.2mm) passive radiators |
| EQ | Yes (via app) |
| IP Rating | IP67 |
| Maximum SPL | 85dBC (Manufacturer specified) |
| Omnidirectional | No |
| Power Bank | No |
| Power Input | USB-C |
| Stereo | Yes |
| Strap | Yes (built-in loop) |
| TWS | Yes |
| Weight | 1.4 lbs (620 g) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Ultimate Ears Boom 4 vs Ultimate Ears Boom 3
- Ultimate Ears Boom 4 vs Ultimate Ears Wonderboom
- Ultimate Ears Boom 4 vs Klipsch Groove
- Ultimate Ears Boom 4 vs Ultimate Ears Wonderboom 2
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- Ultimate Ears Boom 4 vs Ultimate Ears Wonderboom 4
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- Ultimate Ears Boom 4 vs Sony SRS-XE300
- See all 139 comparisons