Short answer: the Harman Kardon Onyx Studio 9. It ranks #15 of 113 boombox speakers by sound quality, rated 4.1/5, at $184.99; the Onn Pro X Large Boom Boombox ranks #49, rated 3.4/5, and costs $199, so there is not much of a tradeoff to weigh.
The Harman Kardon Onyx Studio 9 is the better-sounding, lighter choice. An elegant living room portable with balanced, smooth, non-fatiguing sound, app EQ, and stereo pairing for music lovers. At 9.3 lbs (4.2 kg) it weighs much less than the Onn Pro X Large Boom Boombox at 17.2 lbs (7.8 kg). The catch: It has no water resistance, aux input or USB playback, and its eight-hour claimed battery life is short for an outdoor portable.
The Onn Pro X Large Boom Boombox is the longer-running, tougher pick. A powerful, waterproof party boombox with a 20 hour battery and light modes at a low price. It is rated for 20 hours of battery against 8 for the Harman Kardon Onyx Studio 9. It is rated IP67, while the Harman Kardon Onyx Studio 9 has no water resistance. It keeps a wired aux input, which the Harman Kardon Onyx Studio 9 lacks. The tradeoff: Bass not as deep as higher ranked speakers like the JBL Boombox 3, JBL Boombox 4, or Tribit Stormbox Blast.
Buy the Harman Kardon Onyx Studio 9. It is rated higher for sound quality than the Onn Pro X Large Boom Boombox and costs less, so only choose the other one for a particular feature it does better.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
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Specifications Side By Side
| Harman Kardon Onyx Studio 9 | Onn Pro X Large Boom Boombox | |
|---|---|---|
| Price | $184.99 | $199.00 |
| Ranked | #15 of 113 in Boombox Size Portable Bluetooth Speakers | #49 of 113 in Boombox Size Portable Bluetooth Speakers |
| Bass Extension (-10dB) | 41Hz | - |
| Maximum SPL | 101dB (measured by Alan Ross Reviews) | - |
| IP Rating | None | IP67 |
| Power Input | AC Power Cable (2-Prong) | AC Power cord |
| Stereo | Yes | - |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 9.3 lbs (4.2 kg) | 17.2 lbs (7.8 kg) |
| App | Yes (Harman Kardon One app) | - |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC (inferred; additional codecs unverified) |
| EQ | Yes (App EQ) | Yes (Bass Boost) |
| Party Mode | Yes (Auracast) | Yes (Auracast) |
| USB Playback | No | - |
| Bluetooth Version | 5.3 | 5.4 (Manufacturer specified) |
| Battery Life | 8 hours (Manufacturer specified) | 20 hours (Manufacturer specified) |
| Amplifier Power | 50W RMS | 180W RMS (540W peak) |
| Dimensions | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) | 20.1” x 10.3” x 9” (510 x 261 x 228 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters | 5 speakers |
| Digital Aux Input | No | No |
| Aux Input | No | Yes |
| Strap | No | - |
| Removable Battery | - | No |
| Power Bank | - | Yes (USB-A, 5V/2A) |
| Frequency Response | - | 50Hz - 20kHz (Manufacturer specified) |
| Lights | - | Yes |
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