Short answer: the Sony ULT Field 7. It ranks #61 of 112 boombox speakers by sound quality (rated 3.2/5) at $448 and is still sold new; the Demerbox DB2 ranks #74 (rated 2.8/5) and is discontinued, so it is only an option used.
The Sony ULT Field 7 is the better-sounding choice. A waterproof stereo party speaker with a 30 hour battery and karaoke mic and guitar inputs. It supports LDAC Bluetooth, which the Demerbox DB2 lacks. It links with other speakers (Party Connect up to 100 speakers), which the Demerbox DB2 cannot. It has an adjustable EQ, which the Demerbox DB2 lacks. The tradeoff: A peak around 8kHz, and bass does not reach as deep as the top-ranked speakers.
The Demerbox DB2 is the longer-running, lighter option. A nearly indestructible waterproof speaker built from a Pelican case, with a 40 hour battery and dry storage. It is rated for 40 hours of battery against 30 for the Sony ULT Field 7. At 5.4 lbs (2.47 kg) it weighs much less than the Sony ULT Field 7 at 13.9 lbs (6.3 kg). The catch: Bass is not as deep as better speakers.
Buy the Sony ULT Field 7. It is rated higher for sound quality, and the Demerbox DB2 is discontinued, so it is only available used.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
A waterproof stereo party speaker with a 30 hour battery and karaoke mic and guitar inputs.
A nearly indestructible waterproof speaker built from a Pelican case, with a 40 hour battery and dry storage.
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Specifications Side By Side
| Sony ULT Field 7 | Demerbox DB2 | |
|---|---|---|
| Price | $448.00 | $400 Discontinued |
| Ranked | #61 of 112 in Boombox Size Portable Bluetooth Speakers | #74 of 112 in Boombox Size Portable Bluetooth Speakers |
| Aux Input | Yes | Yes |
| Bass Extension (-10dB) | ~52Hz | - |
| Battery Life | 30 hours (Manufacturer specified) | 40 hours (Manufacturer specified) |
| Guitar Input | Yes | - |
| IP Rating | IP67 | IP67 |
| Microphone Input | Yes (Karaoke mode with echo effect) | - |
| Party Mode | Yes (Party Connect up to 100 speakers) | No |
| Power Bank | Yes (USB-A, 5V/1.5A) | Yes (USB-A + USB-C) |
| Power Input | AC Power cord | AC Power brick |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| USB Playback | Yes | No |
| Weight | 13.9 lbs (6.3 kg) | 5.4 lbs (2.47 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, AAC, LDAC | SBC |
| App | No | No |
| EQ | Yes (App + ULT button) | No |
| TWS | Yes | Yes |
| Built-in Microphone | Yes | No |
| Bluetooth Version | 5.2 | - |
| Dimensions | 20.2” x 8.8” x 8.7” (512 x 224 x 222 mm) | 10.6” x 9.7” x 6.9” (270 x 246 x 175 mm) |
| Amplifier Power | 100W | 22W RMS |
| Drivers | 2x 114mm x 114mm X-Balanced woofers + 2x 46mm (1.9”) tweeters | 2x 3” (76mm) aluminum cone full-range drivers |
| Digital Aux Input | No | No |
| Strap | No | - |
| FM Tuner | - | No |
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