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 $138.
What the Harman Kardon Luna gets right: Pretty balanced sound besides the boosted bass. The tradeoff: Not stereo.
On the Sony ULT Field 3 side: IP67 rated, dustproof and water resistant. The tradeoff: Sounds a bit hollow, a bit boosted in the treble.
Buy the Harman Kardon Luna. It is rated higher for sound quality, and the $152.99 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.
Specifications Side By Side
| Harman Kardon Luna | Sony ULT Field 3 | |
|---|---|---|
| Price | $290.99 | $138.00 |
| Ranked | #24 of 142 in Medium Size Portable Bluetooth Speakers | #60 of 142 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 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) |
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How Harman Kardon Luna compares with other leading options:
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- Soundcore Boost “upgraded” 2021 vs Harman Kardon Luna
- Harman Kardon Luna vs Minirig 4
Prices on this page were last checked September 23, 2026 at 11:24 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Speakers In Full
Harman Kardon Luna: $290.99 Amazon eBay
Pros: Harman Kardon Luna uses 48mm x 90mm woofer, 20mm tweeter. Its 1.13 kg, claimed 12 hours (Manufacturer specified) battery life, IP67 protection and mono playback make it a practical option for its intended room or portable use. Measured bass extension of 57Hz (-10dB).
Cons: Bass is limited by its 57Hz specification. There is no companion app. No EQ adjustment.
Full Harman Kardon Luna review and specifications →
| Amplifier Power | 40W |
|---|---|
| App | No |
| Aux Input | No |
| Bass Extension (-10dB) | 57Hz |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| Digital Aux Input | No |
| Dimensions | 8.3" x 3.1" x 3.1" (210 x 78 x 80 mm) |
| Drivers | 48mm x 90mm woofer, 20mm tweeter |
| EQ | No |
| Frequency Response | 60Hz - 20kHz (Manufacturer specified) |
| IP Rating | IP67 |
| MicroSD Playback | No |
| Omnidirectional | No |
| Power Input | USB-C |
| Stereo | No |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 2.5 lbs (1.13 kg) |
- Links
- Reviews, Comparisons and Sound Samples
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Sony ULT Field 3: $138.00 Amazon eBay
Pros: IP67 rated, dustproof and water resistant. 24 hour battery life. App with 10-band EQ. Party Connect with up to 100 speakers. USB-C in/out for charging your phone.
Cons: Sounds a bit hollow, a bit boosted in the treble. Custom EQ and the ULT bass-boost button can’t be used together - turning on ULT disables the EQ. Bass is very weak with ULT off. Lost to the JBL Charge 6 in a side-by-side comparison despite being the larger speaker.
Full Sony ULT Field 3 review and specifications →
| Amplifier Power | 27W |
|---|---|
| App | Yes |
| Aux Input | No |
| Battery Life | 24 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC, AAC, LDAC |
| Bluetooth Version | 5.2 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 10.1" x 4.4" x 3.1" (256 x 113 x 79 mm) |
| Drivers | 1x 20mm tweeter + 1x 86mm x 46mm woofer |
| EQ | Yes (App + ULT button) |
| IP Rating | IP67 |
| Omnidirectional | No |
| Party Mode | Yes (Party Connect up to 100 speakers) |
| Power Bank | Yes (USB-C, 5V/1.5A) |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| Weight | 2.6 lbs (1.2 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
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