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 Sony ULT Field 3 ranks #71, rated 3.4/5, and costs $208, so there is not much of a tradeoff to weigh.
The Sony ULT Field 3 is the longer-running pick. A rugged waterproof stereo speaker with long battery life, a detailed app EQ, a shoulder strap and a phone charging port. It is rated for 24 hours of battery against 12 for the Harman Kardon Luna 2. It supports LDAC Bluetooth, which the Harman Kardon Luna 2 lacks. It plays in stereo from a single unit, unlike the Harman Kardon Luna 2. Watch for: Sounds a bit hollow, a bit boosted in the treble.
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 much less than the Sony ULT Field 3 at 2.6 lbs (1.2 kg). Watch for: Treble can sound bright and edgy, and it loses more output off-axis than some rivals.
Buy the Harman Kardon Luna 2. It is rated higher for sound quality than the Sony ULT Field 3 and costs less, which makes it the one to get unless you need something the other one does better.
Want more options? Browse the full Portable Bluetooth rankings.
A rugged waterproof stereo speaker with long battery life, a detailed app EQ, a shoulder strap and a phone charging port.
A stylish waterproof speaker with clear, spacious mids, tight bass that stays clean at volume, and stereo pairing with a second unit.
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Specifications Side By Side
| Sony ULT Field 3 | Harman Kardon Luna 2 | |
|---|---|---|
| Price | $208.00 | $199.95 |
| Ranked | #71 of 177 in Medium Size Portable Bluetooth Speakers | #25 of 177 in Medium Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Aux Input | No | No |
| Battery Life | 24 hours (Manufacturer specified) | 12 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, AAC, LDAC | SBC |
| Bluetooth Version | 5.2 | 5.4 |
| Built-in Microphone | Yes | - |
| Dimensions | 10.1” x 4.4” x 3.1” (256 x 113 x 79 mm) | 8.5” x 3.3” x 3.2” (216 x 84 x 81 mm) |
| Drivers | 1x 20mm tweeter + 1x 86mm x 46mm woofer | 62mm x 82mm woofer with passive radiator, 20mm tweeter |
| EQ | Yes (App + ULT button) | Yes (4 presets + custom) |
| IP Rating | IP67 | IP67 |
| Party Mode | Yes (Party Connect up to 100 speakers) | - |
| Power Bank | Yes (USB-C, 5V/1.5A) | - |
| Power Input | USB-C | USB-C |
| Stereo | Yes | No |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 2.6 lbs (1.2 kg) | 1.6 lbs (735 g) |
| Amplifier Power | 27W | 40W (25W woofer + 15W tweeter) |
| Digital Aux Input | No | No |
| Strap | Yes (detachable shoulder strap) | No |
| MicroSD Playback | - | No |
| USB Playback | - | No |
| Frequency Response | - | 58Hz - 20kHz (-6dB) (Manufacturer specified) |
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