Short answer: the JBL Boombox 3. It ranks #27 of 112 boombox speakers by sound quality (rated 3.8/5) at $349.95 and is still sold new; the Diamondboxx M3 ranks #76 (rated 2.8/5) and is discontinued, so it is only an option used.
The JBL Boombox 3 is the better-sounding, tougher option. A loud, fully waterproof boombox with a dedicated subwoofer, a 24 hour battery and power bank charging. It is rated IP67, while the Diamondboxx M3 has no water resistance. It links with other speakers (PartyBoost up to 100 speakers), which the Diamondboxx M3 cannot. The tradeoff: Dips in mid bass range which makes the bass sound undefined, bass boosted, peaky at 700Hz, not quite as good mids and treble as the Blast.
The Diamondboxx M3 is the longer-running, lighter choice. A compact, very loud boombox with a powerful amplifier and a choice of large battery packs. It is rated for 40 hours of battery against 24 for the JBL Boombox 3. At 11 lbs (5 kg) it weighs noticeably less than the JBL Boombox 3 at 14.8 lbs (6.7 kg). The catch: Despite its output, bass does not reach as deep as the best large portables and can distort when pushed hard.
Buy the JBL Boombox 3. It is rated higher for sound quality; the Diamondboxx M3 is no longer sold new.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
A loud, fully waterproof boombox with a dedicated subwoofer, a 24 hour battery and power bank charging.
A compact, very loud boombox with a powerful amplifier and a choice of large battery packs.
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Specifications Side By Side
| JBL Boombox 3 | Diamondboxx M3 | |
|---|---|---|
| Price | $349.95 | $700 Discontinued |
| Ranked | #27 of 112 in Boombox Size Portable Bluetooth Speakers | #76 of 112 in Boombox Size Portable Bluetooth Speakers |
| Aux Input | Yes | Yes |
| Aux Latency | 25ms | - |
| Bass Extension (-10dB) | 43Hz | - |
| Battery Life | 24 hours (Manufacturer specified) | 40 hours (Manufacturer specified) |
| IP Rating | IP67 | None |
| Bluetooth Latency | 100ms | - |
| Maximum SPL | 110dB (measured by Alan Ross Reviews) | - |
| Party Mode | Yes (PartyBoost up to 100 speakers) | No |
| Power Input | AC Power cable | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 14.8 lbs (6.7 kg) | 11 lbs (5 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| App | No | No |
| EQ | No | No |
| Power Bank | Yes (USB-A) | No |
| USB Playback | No | No |
| Built-in Microphone | No | No |
| FM Tuner | No | No |
| Microphone Input | No | - |
| MicroSD Playback | No | - |
| Amplifier Power | 180W AC / 136W battery | 200W RMS / 400W peak |
| Dimensions | 19” x 10.1” x 7.9” (482 x 257 x 200 mm) | 14.7” x 9” x 8” (373.4 x 228.6 x 203.2 mm) |
| Drivers | 1x 189mm subwoofer + 2x 81mm woofers + 2x 20mm tweeters | 3” woofer + tweeter array |
| Digital Aux Input | No | No |
| Bluetooth Version | 5.3 | 5.0 |
| Strap | No | - |
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