Short answer: the Harman Kardon Luna for a more balanced sound, the Sony ULT Field 3 for its IP67 rating. The Sony is dustproof and water resistant but sounds a bit hollow with boosted treble, while the Luna is described as pretty balanced apart from its own boosted bass, and it is not stereo. The Luna costs $290.99 against $208.
Buy the Harman Kardon Luna. It is rated higher for sound quality, and the $82.99 you would save on the Sony ULT Field 3 does not close the gap.
If battery life is a priority, the Sony ULT Field 3 is rated for 24 hours versus 12 hours for the Harman Kardon Luna.
Looking for alternatives? See the complete Portable Bluetooth rankings.
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Specifications Side By Side
| Harman Kardon Luna | Sony ULT Field 3 | |
|---|---|---|
| Price | $290.99 | $208.00 |
| Ranked | #26 of 179 in Medium Size Portable Bluetooth Speakers | #71 of 179 in Medium Size Portable Bluetooth Speakers |
| App | No | Yes |
| Aux Input | No | No |
| Bass Extension (-10dB) | 57Hz | - |
| Battery Life | 12 hours (Manufacturer specified) | 24 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC, AAC, LDAC |
| EQ | No | Yes (App + ULT button) |
| IP Rating | IP67 | IP67 |
| MicroSD Playback | No | - |
| Power Input | USB-C | USB-C |
| Stereo | No | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| USB Playback | Yes | - |
| Weight | 2.5 lbs (1.13 kg) | 2.6 lbs (1.2 kg) |
| Bluetooth Version | 5.3 | 5.2 |
| Dimensions | 8.3” x 3.1” x 3.1” (210 x 78 x 80 mm) | 10.1” x 4.4” x 3.1” (256 x 113 x 79 mm) |
| Drivers | 48mm x 90mm woofer, 20mm tweeter | 1x 20mm tweeter + 1x 86mm x 46mm woofer |
| Frequency Response | 60Hz - 20kHz (Manufacturer specified) | - |
| Amplifier Power | 40W | 27W |
| Digital Aux Input | No | No |
| Built-in Microphone | - | Yes |
| Party Mode | - | Yes (Party Connect up to 100 speakers) |
| Power Bank | - | Yes (USB-C, 5V/1.5A) |
| Strap | - | Yes (detachable shoulder strap) |
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