Short answer: the Harman Kardon Luna 2. It ranks #25 of 179 medium speakers by sound quality, rated 4.1/5, at $199.95. The Tribit Stormbox Flow ranks #58, rated 3.5/5, at $79.99, $119.96 cheaper, which does not close the gap in sound quality.
The Harman Kardon Luna 2 is the better-sounding option. A stylish waterproof speaker with clear, spacious mids, tight bass that stays clean at volume, and stereo pairing with a second unit. The catch: Treble can sound bright and edgy, and it loses more output off-axis than some rivals.
The Tribit Stormbox Flow is the longer-running option. A waterproof speaker with very long battery life, a carry handle, stereo pairing and a port that charges your phone. It is rated for 30 hours of battery against 12 for the Harman Kardon Luna 2. It supports AAC Bluetooth, which the Harman Kardon Luna 2 lacks. The tradeoff: Midrange and bass are weirdly recessed about 4db below 700Hz.
Buy the Harman Kardon Luna 2. It is rated higher for sound quality, and the $119.96 you would save on the Tribit Stormbox Flow does not close the gap.
Looking for alternatives? See the complete Portable Bluetooth rankings.
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Specifications Side By Side
| Harman Kardon Luna 2 | Tribit Stormbox Flow | |
|---|---|---|
| Price | $199.95 | $79.99 |
| Ranked | #25 of 179 in Medium Size Portable Bluetooth Speakers | #58 of 179 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Aux Input | No | No |
| Battery Life | 12 hours (Manufacturer specified) | 30 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC, AAC |
| EQ | Yes (4 presets + custom) | Yes |
| IP Rating | IP67 | IPX7 |
| MicroSD Playback | No | - |
| Power Input | USB-C | USB-C |
| Stereo | No | No |
| Omnidirectional | No | Pointing up |
| TWS | Yes | Yes |
| USB Playback | No | - |
| Weight | 1.6 lbs (735 g) | 1.4 lbs (657 g) |
| Bluetooth Version | 5.4 | 5.3 |
| Dimensions | 8.5” x 3.3” x 3.2” (216 x 84 x 81 mm) | 7.9” x 3.6” x 2.1” (200 x 91 x 53 mm) |
| Drivers | 62mm x 82mm woofer with passive radiator, 20mm tweeter | 60W: 2x 30mm drivers + passive radiators |
| Frequency Response | 58Hz - 20kHz (-6dB) (Manufacturer specified) | 50Hz - 20kHz (Manufacturer specified) |
| Amplifier Power | 40W (25W woofer + 15W tweeter) | 25W |
| Digital Aux Input | No | No |
| Strap | No | - |
| Bass Extension (-10dB) | - | 47Hz |
| Bluetooth Latency | - | 400ms aac, 200ms sbc |
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