These sit in different size classes, so this is not a straight ranking comparison. The Harman Kardon Luna 2 ranks #25 of 179 medium speakers by sound quality at $199.95; the Marshall Stockwell III ranks #84 of 120 large speakers by sound quality at $249.99.
The Harman Kardon Luna 2 is the lighter, tougher choice. 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 much less than the Marshall Stockwell III at 2.9 lbs (1.3 kg). It is rated IP67 against IP55 for the Marshall Stockwell III. The catch: Treble can sound bright and edgy, and it loses more output off-axis than some rivals.
The Marshall Stockwell III is the longer-running option. A stylish, rugged speaker with a very long battery you can swap yourself, a detailed app EQ, and power bank charging. It is rated for 40 hours of battery against 12 for the Harman Kardon Luna 2. It supports AAC Bluetooth, which the Harman Kardon Luna 2 lacks. It keeps a wired aux input, which the Harman Kardon Luna 2 lacks. The tradeoff: Highs are recessed by default and need the treble control maxed to compensate, still lacking detail even then.
Buy the Harman Kardon Luna 2 ($199.95) for a medium speaker; the Marshall Stockwell III ($249.99) suits a large speaker instead.
Looking for alternatives? See the complete Portable Bluetooth rankings.
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Specifications Side By Side
| Harman Kardon Luna 2 | Marshall Stockwell III | |
|---|---|---|
| Price | $199.95 | $249.99 |
| Ranked | #25 of 179 in Medium Size Portable Bluetooth Speakers | #84 of 120 in Large Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Aux Input | No | Yes |
| Battery Life | 12 hours (Manufacturer specified) | 40+ hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC, AAC, LE Audio with LC3 |
| EQ | Yes (4 presets + custom) | Yes (parametric, via app) |
| IP Rating | IP67 | IP55 |
| MicroSD Playback | No | - |
| Power Input | USB-C | USB-C |
| Stereo | No | Partially |
| Omnidirectional | No | Yes |
| TWS | Yes | No |
| USB Playback | No | - |
| Weight | 1.6 lbs (735 g) | 2.9 lbs (1.3 kg) |
| Bluetooth Version | 5.4 | 5.3 |
| Dimensions | 8.5” x 3.3” x 3.2” (216 x 84 x 81 mm) | 7.1” x 6.4” x 2.9” (180 x 162 x 74 mm) |
| Drivers | 62mm x 82mm woofer with passive radiator, 20mm tweeter | 1x 3” woofer, 2x 1.75” wide-band drivers |
| Frequency Response | 58Hz - 20kHz (-6dB) (Manufacturer specified) | 54Hz - 20kHz (Manufacturer specified) |
| Amplifier Power | 40W (25W woofer + 15W tweeter) | 44W |
| Digital Aux Input | No | No |
| Strap | No | Yes (detachable strap) |
| Power Bank | - | Yes |
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