Short answer: the Harman Kardon Luna 2 for better sound, the Ultimate Ears Boom 3 for ruggedness and battery. The Boom 3 is IP67 rated, floats, pairs up to 150 speakers in PartyUp and runs 15 hours, but our notes flag barely any bass, recessed treble and micro USB on a 2021 product. The Luna 2 delivers the articulate midrange and controlled bass at $199.95 versus $134.99.
Buy the Harman Kardon Luna 2. It is rated higher for sound quality, and the $64.96 you would save on the Ultimate Ears Boom 3 does not close the gap.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Articulate, spacious midrange with precise imaging and instrument separation.
Amazon $199.95 B&H Photo Video $199.95 eBay
A rugged 608 g IP67 speaker that floats, with a 15-hour battery and a fabric shell.
Amazon $134.99 eBayPrices on this page were last checked October 15, 2026 at 5:41 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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Specifications Side By Side
| Harman Kardon Luna 2 | Ultimate Ears Boom 3 | |
|---|---|---|
| Price | $199.95 | $134.99 |
| Ranked | #25 of 172 in Medium Size Portable Bluetooth Speakers | #111 of 172 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes (Ultimate Ears BOOM & MEGABOOM app) |
| Aux Input | No | No |
| Battery Life | 12 hours (Manufacturer specified) | 15 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | 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) | - |
| Amplifier Power | 40W (25W woofer + 15W tweeter) | - |
| Digital Aux Input | No | No |
| Strap | No | Yes (built-in loop) |
| Bass Extension (-10dB) | - | 91Hz |
| Party Mode | - | Yes (PartyUp up to 50 speakers) |
| Built-in Microphone | - | No |
| Maximum SPL | - | 87dB (Manufacturer specified) |
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