Short answer: the Harman Kardon Luna 2 if sound quality matters most, the Ultimate Ears Boom 3 if price matters most. The Harman Kardon Luna 2 ranks #22 of 138 medium speakers at $199.95. The Ultimate Ears Boom 3 ranks #91 at $129.90, $70.05 cheaper.
What the Harman Kardon Luna 2 offers: Articulate, spacious midrange with precise imaging and instrument separation. Tight, well-controlled bass from the 62mm x 82mm woofer and passive radiator despite the compact body, and it stays cleaner at volume than pricier rivals like the Sonos Play. Set against that: Treble can sound bright and edgy, and it loses more output off-axis than some rivals. Some listeners hear mid-range rattling on certain tracks, similar to sibling JBL models. 12-hour battery life trails category leaders like the JBL Charge 6, which doubles it.
On the Ultimate Ears Boom 3 side: 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 The catch: 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.
Buy the Harman Kardon Luna 2 when sound quality outweighs the price for you, and the Ultimate Ears Boom 3 when the price outweighs sound quality instead.
Specifications Side By Side
| Harman Kardon Luna 2 | Ultimate Ears Boom 3 | |
|---|---|---|
| Price | $199.95 | $129.90 |
| Ranked | #22 of 138 in Medium Size Portable Bluetooth Speakers | #91 of 138 in Medium Size Portable Bluetooth Speakers |
| App | Yes | - |
| Aux Input | No | - |
| Battery Life | 12 hours (Manufacturer specified) | 15 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC | - |
| EQ | Yes (4 presets + custom) | Yes (via app) |
| IP Rating | IP67 | IP67 |
| MicroSD Playback | No | - |
| Power Input | USB-C | Micro USB |
| Stereo | No | Yes |
| Omnidirectional | No | Yes |
| TWS | Yes | Yes |
| USB Playback | No | - |
| Weight | 1.6 lbs / 735 g | 1.3 lbs / 608 g |
| Bluetooth Version | 5.4 | 4.2 |
| Dimensions | 8.5" x 3.3" x 3.2" (216 x 84 x 81 mm) | 7.2" x 2.9" (184 x 73 mm) |
| Drivers | 62mm x 82mm woofer with passive radiator, 20mm tweeter | 2x 2" active drivers + 2x 2" x 4" passive radiators |
| Frequency Response | 58Hz - 20kHz (-6dB) (Manufacturer specified) | - |
| Output Power | 40W (25W woofer + 15W tweeter) | - |
| Digital Aux Input | No | No |
| Bass Extension (-10dB) | - | 91Hz |
| Party Mode | - | Yes (PartyUp up to 50 speakers) |
| Built in Microphone | - | No |
| Max Volume | - | 87dB |
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- Tribit Maxsound Plus V1/V2/Thunderbox Plus vs JBL Charge 5 Wifi
- JBL Charge 6 vs Ultimate Ears Boom 3
- Harman Kardon Luna 2 vs JBL Flip 7
Prices on this page were last checked September 1, 2026 at 2:15 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
Harman Kardon Luna 2: $199.95 Amazon B&H Photo Video eBay
Pros: Articulate, spacious midrange with precise imaging and instrument separation. Tight, well-controlled bass from the 62mm x 82mm woofer and passive radiator despite the compact body, and it stays cleaner at volume than pricier rivals like the Sonos Play. IP67 rated, and two units pair via AirTouch for true stereo sound.
Cons: Treble can sound bright and edgy, and it loses more output off-axis than some rivals. Some listeners hear mid-range rattling on certain tracks, similar to sibling JBL models. 12-hour battery life trails category leaders like the JBL Charge 6, which doubles it. Single unit is not stereo (1.1 driver layout).
Full Harman Kardon Luna 2 review and specifications →
| App | Yes |
|---|---|
| Aux Input | No |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.4 |
| Digital Aux Input | No |
| Dimensions | 8.5" x 3.3" x 3.2" (216 x 84 x 81 mm) |
| Drivers | 62mm x 82mm woofer with passive radiator, 20mm tweeter |
| EQ | Yes (4 presets + custom) |
| Frequency Response | 58Hz - 20kHz (-6dB) (Manufacturer specified) |
| IP Rating | IP67 |
| MicroSD Playback | No |
| Omnidirectional | No |
| Output Power | 40W (25W woofer + 15W tweeter) |
| Power Input | USB-C |
| Stereo | No |
| TWS | Yes |
| USB Playback | No |
| Weight | 1.6 lbs / 735 g |
- Links
- Reviews, Comparisons and Sound Samples
- What Hi-Fi?: Harman Kardon Luna 2 review
- Joy & Oluv’Sone: Sonos Play & Harman Kardon Luna 2 - listening test More from Oluv’Sone →
- Mateusz Cholewa: Harman Kardon Luna 2 UNBOXING vs HK Luna Short Test More from Mateusz Cholewa →
- Storytripper HD: Harman Kardon Luna vs Luna 2 More from storytripperhd →
- Head-to-Head Comparisons
- Harman Kardon Luna 2 vs JBL Charge 5
- Harman Kardon Luna 2 vs JBL Flip 7
- Harman Kardon Luna 2 vs JBL Flip 6
- Harman Kardon Luna 2 vs JBL Charge 6
- Harman Kardon Luna 2 vs Tribit Xsound Plus 2
- Harman Kardon Luna 2 vs Bose Soundlink Flex 2nd gen
- Harman Kardon Luna 2 vs Bose Soundlink Flex
- Harman Kardon Luna 2 vs Soundcore Motion 300
- See all 29 comparisons
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 78 comparisons