These are not really the same size class, and that is the honest framing here. The Harman Kardon Onyx Studio 9 ranks #15 of 113 boombox speakers by sound quality at $184.99; the JBL Xtreme 4 ranks #43 of 120 large speakers by sound quality at $309.95.
Why pick the Harman Kardon Onyx Studio 9: An elegant living room portable with balanced, smooth, non-fatiguing sound, app EQ, and stereo pairing for music lovers. 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 JBL Xtreme 4 is the louder, longer-running choice. A rugged, waterproof speaker with clear, punchy sound, a swappable battery, a power bank and excellent real world battery life. Alan Ross Reviews measured it at 106dB at full volume, against 101dB for the Harman Kardon Onyx Studio 9. It is rated for 24 hours of battery against 8 for the Harman Kardon Onyx Studio 9. At 4.6 lbs (2.1 kg) it weighs much less than the Harman Kardon Onyx Studio 9 at 9.3 lbs (4.2 kg). The tradeoff: It cannot produce the deep rumble of a larger speaker, and bass compression increases near maximum volume.
Buy the Harman Kardon Onyx Studio 9 at $184.99 for a boombox speaker, or the JBL Xtreme 4 at $309.95 for a large speaker instead.
Want more options? Browse the full Portable Bluetooth rankings.
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Specifications Side By Side
| Harman Kardon Onyx Studio 9 | JBL Xtreme 4 | |
|---|---|---|
| Price | $184.99 | $309.95 |
| Ranked | #15 of 113 in Boombox Size Portable Bluetooth Speakers | #43 of 120 in Large Size Portable Bluetooth Speakers |
| Bass Extension (-10dB) | 41Hz | - |
| Maximum SPL | 101dB (measured by Alan Ross Reviews) | 106dB (measured by Alan Ross Reviews) |
| IP Rating | None | IP67 |
| Power Input | AC Power Cable (2-Prong) | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 9.3 lbs (4.2 kg) | 4.6 lbs (2.1 kg) |
| App | Yes (Harman Kardon One app) | Yes |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| EQ | Yes (App EQ) | Yes (5 band) |
| Party Mode | Yes (Auracast) | Yes (Auracast) |
| USB Playback | No | - |
| Bluetooth Version | 5.3 | 5.3 |
| Battery Life | 8 hours (Manufacturer specified) | 24 hours (Manufacturer specified) |
| Amplifier Power | 50W RMS | 100W |
| Dimensions | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) | 11.7” x 5.9” x 5.6” (297 x 149 x 141 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters | 2x 70mm woofers, 2x 19mm tweeters + 2x passive radiators |
| Digital Aux Input | No | No |
| Aux Input | No | No |
| Strap | No | Yes (detachable shoulder strap) |
| Bluetooth Latency | - | 220ms |
| Power Bank | - | Yes (USB-C) |
| Removable Battery | - | Yes |
| Built-in Microphone | - | Yes |
| Frequency Response | - | 44Hz - 20kHz (Manufacturer specified) |
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