Short answer: the Zealot S89. It ranks #19 of 112 boombox speakers by sound quality (rated 4.0/5) at $193.58 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 Zealot S89 is the better-sounding, tougher pick. A great value boombox with deep bass, very high volume, a 40 hour battery and water resistance for outdoor parties. It is rated IPX6, while the Diamondboxx M3 has no water resistance. It links with other speakers (PartyAdd up to 100 speakers), which the Diamondboxx M3 cannot. It has an adjustable EQ, which the Diamondboxx M3 lacks. The tradeoff: At high volume, listener reports describe the bass as loose or muddy and the overall balance as less clear than better boombox speakers.
The Diamondboxx M3 is the lighter choice. A compact, very loud boombox with a powerful amplifier and a choice of large battery packs. At 11 lbs (5 kg) it weighs noticeably less than the Zealot S89 at 16.1 lbs (7.3 kg). Watch for: Despite its output, bass does not reach as deep as the best large portables and can distort when pushed hard.
Buy the Zealot S89. It is rated higher for sound quality, and the Diamondboxx M3 is discontinued, so it is only available used.
Looking for alternatives? See the complete Portable Bluetooth rankings.
A great value boombox with deep bass, very high volume, a 40 hour battery and water resistance for outdoor parties.
A compact, very loud boombox with a powerful amplifier and a choice of large battery packs.
Prices on this page were last checked October 31, 2026 at 7:11 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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Specifications Side By Side
| Zealot S89 | Diamondboxx M3 | |
|---|---|---|
| Price | $193.58 | $700 Discontinued |
| Ranked | #19 of 112 in Boombox Size Portable Bluetooth Speakers | #76 of 112 in Boombox Size Portable Bluetooth Speakers |
| App | No | No |
| Aux Input | Yes | Yes |
| Bass Extension (-10dB) | 36Hz | - |
| Battery Life | 40 hours (Manufacturer specified) | 40 hours (Manufacturer specified) |
| EQ | Yes (multiple modes) | No |
| IP Rating | IPX6 | None |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| MicroSD Playback | Yes | - |
| Party Mode | Yes (PartyAdd up to 100 speakers) | No |
| Power Input | USB-C | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 16.1 lbs (7.3 kg) | 11 lbs (5 kg) |
| Power Bank | Yes (USB-A + USB-C) | No |
| USB Playback | Yes | No |
| Built-in Microphone | No | No |
| Amplifier Power | 250W | 200W RMS / 400W peak |
| Dimensions | 21.2” x 10.4” x 9.4” (538 x 265 x 240 mm) | 14.7” x 9” x 8” (373.4 x 228.6 x 203.2 mm) |
| Drivers | 130W subwoofer + 2x 40mm drivers + 2x tweeters | 3” woofer + tweeter array |
| Digital Aux Input | No | No |
| Bluetooth Version | 5.3 | 5.0 |
| Strap | No | - |
| FM Tuner | - | No |
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