Short answer: the Harman Kardon Luna 2. It ranks #25 of 177 medium speakers by sound quality, rated 4.1/5, at $199.95; the Ultimate Ears Megaboom 4 ranks #171, rated 2.1/5, and costs $200, which makes this an easy call rather than a real tradeoff.
The Harman Kardon Luna 2 is the better-sounding, lighter option. A stylish waterproof speaker with clear, spacious mids, tight bass that stays clean at volume, and stereo pairing with a second unit. At 1.6 lbs (735 g) it weighs noticeably less than the Ultimate Ears Megaboom 4 at 2.4 lbs (1.1 kg). Watch for: Treble can sound bright and edgy, and it loses more output off-axis than some rivals.
The Ultimate Ears Megaboom 4 is the longer-running pick. A tough waterproof speaker that floats, with USB-C charging, a long battery and PartyUp linking. It is rated for 20 hours of battery against 12 for the Harman Kardon Luna 2. The catch: A lot of distortion at higher volumes.
Buy the Harman Kardon Luna 2. It is rated higher for sound quality than the Ultimate Ears Megaboom 4 and costs less, so it is the default pick unless a specific strength of the other one matters more to you.
Want more options? Browse the full Portable Bluetooth rankings.
A stylish waterproof speaker with clear, spacious mids, tight bass that stays clean at volume, and stereo pairing with a second unit.
A tough waterproof speaker that floats, with USB-C charging, a long battery and PartyUp linking.
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Specifications Side By Side
| Harman Kardon Luna 2 | Ultimate Ears Megaboom 4 | |
|---|---|---|
| Price | $199.95 | $200 |
| Ranked | #25 of 177 in Medium Size Portable Bluetooth Speakers | #171 of 177 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Aux Input | No | No |
| Battery Life | 12 hours (Manufacturer specified) | 20 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 | USB-C |
| Stereo | No | No |
| Omnidirectional | No | Yes |
| TWS | Yes | Yes |
| USB Playback | No | - |
| Weight | 1.6 lbs (735 g) | 2.4 lbs (1.1 kg) |
| Bluetooth Version | 5.4 | 5.1 |
| Dimensions | 8.5” x 3.3” x 3.2” (216 x 84 x 81 mm) | 3.4” x 3.4” x 8.9” (87 x 87 x 225 mm) |
| Drivers | 62mm x 82mm woofer with passive radiator, 20mm tweeter | 2x 50x50mm full-range + 2x 55x86mm 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) |
| Party Mode | - | Yes (PartyUp up to 50 speakers) |
| Built-in Microphone | - | No |
| Maximum SPL | - | 91dB (Manufacturer specified) |
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