Short answer: the Zealot ZE21, because the Yeahbox’s specs are manufacturer claims. The Sonic Boom Max 3 advertises 200W RMS and 300W peak from a true 3-way, 5-driver array, but independent testing of the budget import brand is limited. The ZE21 is great value for bass, play time and max volume in the boombox class, though its top end is a little rolled off and it is not balanced.
Buy the Zealot ZE21. It is rated higher for sound quality than the Yeahbox Sonic Boom Max 3 and costs less, so only choose the other one for a particular feature it does better.
Looking for alternatives? See the complete Portable Bluetooth rankings.
A large party speaker with powerful bass, a big fast charging battery and app EQ for outdoor parties.
A rugged battery boombox with unusually deep bass, very long battery life, and stereo pairing for party scale sound.
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Specifications Side By Side
| Yeahbox Sonic Boom Max 3 | Zealot ZE21 | |
|---|---|---|
| Price | $228.99 | $187.15 |
| Ranked | #59 of 113 in Boombox Size Portable Bluetooth Speakers | #18 of 113 in Boombox Size Portable Bluetooth Speakers |
| App | Yes | No |
| Aux Input | Yes | Yes |
| Battery Life | 111Wh (14.8V/7,500mAh) (Manufacturer specified) | 40 hours (Manufacturer specified) |
| EQ | Yes | Yes (multiple modes) |
| IP Rating | IPX6 | IPX6 |
| MicroSD Playback | Yes | Yes |
| Power Input | USB-C | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 16.8 lbs (7.64 kg) | 20.4 lbs (9.27 kg) |
| USB Playback | Yes | Yes |
| Amplifier Power | 200W RMS / 300W Peak | 250W |
| Dimensions | 20.7” x 8.3” x 10.6” (525 x 210 x 268 mm) | 16.7” x 10.3” x 14.3” (424 x 262 x 363 mm) |
| Drivers | 189x114mm woofer, 2x 89mm midrange, 2x 38mm tweeters | 130W subwoofer + 2x 50mm woofers + passive radiators |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | 5.3 |
| Digital Aux Input | No | No |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) | SBC |
| Lights | Yes | - |
| Strap | No | - |
| Bass Extension (-10dB) | - | 36Hz |
| Party Mode | - | Yes (PartyAdd up to 100 speakers) |
| Power Bank | - | Yes (USB-A + USB-C) |
| Built-in Microphone | - | No |
| Maximum SPL | - | 116dB (Manufacturer specified) |
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