Short answer: the Harman Kardon Luna. It ranks #26 of 175 medium speakers by sound quality, rated 4.0/5, at $290.99. The Ultimate Ears Boom 3 ranks #114, rated 2.9/5, at $134.99, $156 cheaper, not enough of a saving to outweigh the sound-quality gap.
The Harman Kardon Luna is the better-sounding, deeper-bass option. The sound is fairly balanced apart from the boosted bass. Its bass reaches about 57Hz before falling 10dB, against 91Hz for the Ultimate Ears Boom 3. It charges over USB-C rather than Micro USB. Watch for: Boosted bass, and less detailed than higher-ranked speakers.
The Ultimate Ears Boom 3 is the lighter choice. 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. At 1.3 lbs (608 g) it weighs much less than the Harman Kardon Luna at 2.5 lbs (1.13 kg). It has an adjustable EQ, which the Harman Kardon Luna lacks. It plays in stereo from a single unit, unlike the Harman Kardon Luna. The catch: Not stereo, barely any bass, recessed treble.
Buy the Harman Kardon Luna. It is rated higher for sound quality, and the $156 saving on the Ultimate Ears Boom 3 is not enough to make up the difference.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Harman Kardon Luna | Ultimate Ears Boom 3 | |
|---|---|---|
| Price | $290.99 | $134.99 |
| Ranked | #26 of 175 in Medium Size Portable Bluetooth Speakers | #114 of 175 in Medium Size Portable Bluetooth Speakers |
| App | No | Yes (Ultimate Ears BOOM & MEGABOOM app) |
| Aux Input | No | No |
| Bass Extension (-10dB) | 57Hz | 91Hz |
| Battery Life | 12 hours (Manufacturer specified) | 15 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| EQ | No | 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 | Yes | - |
| Weight | 2.5 lbs (1.13 kg) | 1.3 lbs (608 g) |
| Bluetooth Version | 5.3 | 4.2 |
| Dimensions | 8.3” x 3.1” x 3.1” (210 x 78 x 80 mm) | 7.2” x 2.9” (184 x 73 mm) |
| Drivers | 48mm x 90mm woofer, 20mm tweeter | 2x 2” active drivers + 2x 2” x 4” passive radiators |
| Frequency Response | 60Hz - 20kHz (Manufacturer specified) | - |
| Amplifier Power | 40W | - |
| Digital Aux Input | No | No |
| Party Mode | - | Yes (PartyUp up to 50 speakers) |
| Built-in Microphone | - | No |
| Maximum SPL | - | 87dB (Manufacturer specified) |
| Strap | - | Yes (built-in loop) |
Related Speaker Comparisons
More worthwhile head-to-heads for Harman Kardon Luna:
- Harman Kardon Luna vs EarFun Uboom L
- Soundcore Motion 300 vs Harman Kardon Luna
- Soundcore Motion+ vs Harman Kardon Luna
- Soundcore Boost “upgraded” 2021 vs Harman Kardon Luna
- Harman Kardon Luna 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
Harman Kardon Luna: $290.99 Amazon $290.99 eBay
Newer model: the Harman Kardon Luna 2, ranked higher, rated 4.1/5, released Mar 2026. It adds app control and adjustable EQ. See every Harman Kardon Luna generation.
Pros: Harman Kardon Luna uses 48mm x 90mm woofer, 20mm tweeter. Its 1.13 kg, claimed 12 hours (Manufacturer specified) battery life, IP67 protection and mono playback make it a practical option for its intended room or portable use. The sound is fairly balanced apart from the boosted bass. Measured bass extension of 57Hz (-10dB).
Cons: Bass is limited by its 57Hz specification. There is no companion app. No EQ adjustment. Boosted bass, and less detailed than higher-ranked speakers.
Full Harman Kardon Luna review and specifications →
| Released | Sep 2023 (3 years ago) |
|---|---|
| Amplifier Power | 40W |
| App | No |
| Aux Input | No |
| Bass Extension (-10dB) | 57Hz |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| Digital Aux Input | No |
| Dimensions | 8.3” x 3.1” x 3.1” (210 x 78 x 80 mm) |
| Drivers | 48mm x 90mm woofer, 20mm tweeter |
| EQ | No |
| Frequency Response | 60Hz - 20kHz (Manufacturer specified) |
| IP Rating | IP67 |
| MicroSD Playback | No |
| Omnidirectional | No |
| Power Input | USB-C |
| Stereo | No |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 2.5 lbs (1.13 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Oluv Patreon: Harman Kardon Luna - sound demo More from Oluv’Sone →
- Alan Ross - The Anti Shill!: Onyx Studio 9 or Go Play 3? Or even the HK Luna?? More from alanrossreviews →
- Alan Ross Reviews: Beats Pill vs Harman Luna vs Bose Flex vs Soundcore Motion Plus
- 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 →
- Storytripper HD: Klipsch Nashville vs Harman Kardon Luna vs Soundcore Motion 300
- Storytripper HD: Huawei Sound Joy 2 vs Tribit XSound Plus 2 vs Harman Kardon Luna
- Head-to-Head Comparisons
- Harman Kardon Luna vs Harman Kardon Luna 2
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- See all 136 comparisons
Ultimate Ears Boom 3: $134.99 Amazon $134.99 eBay
Newer model: the Ultimate Ears Boom 4, ranked higher, rated 2.9/5, released Jun 2024. See every Ultimate Ears Wonderboom, Boom and Megaboom generation.
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. Measured bass extension of 91Hz (-10dB).
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 →
| Released | Sep 2018 (8 years ago) |
|---|---|
| App | Yes (Ultimate Ears BOOM & MEGABOOM app) |
| Aux Input | No |
| Bass Extension (-10dB) | 91Hz |
| Battery Life | 15 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| 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 |
| Maximum SPL | 87dB (Manufacturer specified) |
| Omnidirectional | Yes |
| Party Mode | Yes (PartyUp up to 50 speakers) |
| Power Input | Micro USB |
| Stereo | Yes |
| Strap | Yes (built-in loop) |
| 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
- Ultimate Ears Boom 3 vs Ultimate Ears Wonderboom
- Ultimate Ears Boom 3 vs Ultimate Ears Wonderboom 2
- Ultimate Ears Boom 3 vs Sony SRS-XE300
- Ultimate Ears Boom 3 vs Ultimate Ears Wonderboom 3
- Ultimate Ears Boom 3 vs Tribit Stormbox
- Ultimate Ears Boom 3 vs Ultimate Ears Wonderboom 4
- See all 99 comparisons