Short answer: the Zealot ZE51. It ranks #16 of 112 boombox speakers by sound quality, rated 4.1/5, at $235.33. The Onn Medium Party Speaker Gen 2 ranks #65, rated 3.1/5, at $90, $145.33 cheaper, not enough of a saving to outweigh the sound-quality gap.
The Zealot ZE51 is the better-sounding option. A big stereo boombox with clean, wide sound and low distortion at high volume for outdoor parties. It has an adjustable EQ, which the Onn Medium Party Speaker Gen 2 lacks. It plays in stereo from a single unit, unlike the Onn Medium Party Speaker Gen 2. The catch: The Zealot ZE41 still wins on raw bass depth and price.
The Onn Medium Party Speaker Gen 2 is the longer-running, lighter pick. An affordable waterproof party speaker with a big woofer, lights, a karaoke mic input and FM radio. It is rated for 20 hours of battery against 4 for the Zealot ZE51. At 11 lbs (5 kg) it weighs much less than the Zealot ZE51 at 26 lbs (11.81 kg). It is rated IPX7 against IPX5 for the Zealot ZE51. The tradeoff: Lacking detail compared to the Onn Large Party gen 2 and not as deep of bass.
Buy the Zealot ZE51. It is rated higher for sound quality, and saving $145.33 with the Onn Medium Party Speaker Gen 2 does not make up for the sound-quality gap.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
A big stereo boombox with clean, wide sound and low distortion at high volume for outdoor parties.
An affordable waterproof party speaker with a big woofer, lights, a karaoke mic input and FM radio.
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 ZE51 | Onn Medium Party Speaker Gen 2 | |
|---|---|---|
| Price | $235.33 after coupon | $90 |
| Ranked | #16 of 112 in Boombox Size Portable Bluetooth Speakers | #65 of 112 in Boombox Size Portable Bluetooth Speakers |
| App | Yes | No |
| Aux Input | Yes | Yes |
| Battery Capacity | 48000mAh (12x4000mAh) | - |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 5.3 | - |
| Dimensions | 22.1” x 9.4” x 13” (562 x 238 x 331 mm) | 9.6” x 10.9” x 15.1” (244.1 x 277.9 x 383 mm) |
| EQ | Yes (Hi-Res, 3D Surround, Extra Bass, Vocal and other sound modes) | No |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) | - |
| IP Rating | IPX5 | IPX7 |
| Microphone Input | Yes (Karaoke mode) | Yes (Karaoke mode with echo effect) |
| MicroSD Playback | Yes | - |
| Amplifier Power | 250W | 50W RMS / 200W peak |
| Power Bank | Yes (USB-A + USB-C) | Yes (USB-A, 5V/2.1A) |
| Power Input | Type-C | AC Power cord |
| Stereo | Yes | No |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| USB Playback | Yes | No |
| Weight | 26 lbs (11.81 kg) | 11 lbs (5 kg) |
| Digital Aux Input | No | No |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) | SBC |
| Drivers | 1x 133mm + 2x 93mm + 2x 45mm | 8” (203mm) woofer + tweeters |
| Battery Life | 4 hours (Manufacturer specified) | 20 hours (Manufacturer specified) |
| Strap | Yes (strap) | - |
| FM Tuner | - | Yes (16 presets) |
| Party Mode | - | Yes (Party Sync Mode) |
| Built-in Microphone | - | No |
| Lights | - | Yes |
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