These are not really the same size class, and that is the honest framing here. The Harman Kardon Onyx Studio 9 ranks #15 of 76 boombox speakers by sound quality at $189.99; the JBL Xtreme 4 ranks #40 of 82 large speakers by sound quality at $309.95.
Why pick the Harman Kardon Onyx Studio 9: An elegant 4.2kg living-room portable with a measured 41Hz -10dB bass point, 101dB maximum level, three tweeters, app EQ, stereo pairing and Auracast multi-speaker linking. 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.
Why pick the JBL Xtreme 4: A rugged 2.1kg portable with IP67 protection, a replaceable battery, USB-C power-bank output, Auracast, stereo pairing and a useful 5-band app EQ. The catch: 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 $189.99 for a boombox speaker, or the JBL Xtreme 4 at $309.95 for a large speaker instead.
There is a real battery-life gap here: the JBL Xtreme 4 is rated for 24 hours, the Harman Kardon Onyx Studio 9 only 8 hours.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| Harman Kardon Onyx Studio 9 | JBL Xtreme 4 | |
|---|---|---|
| Price | $189.99 | $309.95 |
| Ranked | #15 of 76 in Boombox Size Portable Bluetooth Speakers | #40 of 82 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 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) |
Related Speaker Comparisons
More top alternatives to Harman Kardon Onyx Studio 9:
- Earfun Uboom X vs Harman Kardon Onyx Studio 9
- Harman Kardon Onyx Studio 9 vs Tribit Stormbox Blast
- Harman Kardon Go + Play 3 vs Harman Kardon Onyx Studio 9
- JBL Partybox Encore 2 vs Harman Kardon Onyx Studio 9
- Harman Kardon Onyx Studio 9 vs JBL Partybox Encore Essential 2
Prices on this page were last checked September 26, 2026 at 11:14 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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The Two Speakers In Full
Harman Kardon Onyx Studio 9: $189.99 Amazon eBay
Older models: the Harman Kardon Onyx Studio 8 (rated 4.1/5), the Harman Kardon Onyx Studio 7 (rated 4.1/5), the Harman Kardon Onyx Studio 6 (rated 4.1/5), the Harman Kardon Onyx Studio 5 (rated 3.9/5) and the Harman Kardon Onyx Studio 4 (rated 3.3/5).
Pros: An elegant 4.2kg living-room portable with a measured 41Hz -10dB bass point, 101dB maximum level, three tweeters, app EQ, stereo pairing and Auracast multi-speaker linking. Reviews praise its balanced, smooth presentation and non-fatiguing treble, making it a more music-focused choice than most party speakers. Measured bass extension of 41Hz (-10dB).
Cons: It has no water resistance, aux input or USB playback, and its eight-hour claimed battery life is short for an outdoor portable. Bass is less deep than some earlier Onyx Studio models, while the slightly recessed mids and rolled-off top end mean it is not the most open or detailed option; it still charges from an AC power cable rather than USB-C.
Full Harman Kardon Onyx Studio 9 review and specifications →
| Amplifier Power | 50W RMS |
|---|---|
| App | Yes (Harman Kardon One app) |
| Aux Input | No |
| Bass Extension (-10dB) | 41Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| Digital Aux Input | No |
| Dimensions | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters |
| EQ | Yes (App EQ) |
| IP Rating | None |
| Maximum SPL | 101dB (measured by Alan Ross Reviews) |
| Omnidirectional | No |
| Party Mode | Yes (Auracast) |
| Power Input | AC Power Cable (2-Prong) |
| Stereo | Yes |
| Strap | No |
| TWS | Yes |
| USB Playback | No |
| Weight | 9.3 lbs (4.2 kg) |
- Links
- Reviews, Comparisons and Sound Samples
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JBL Xtreme 4: $309.95 Amazon B&H Photo Video eBay
Newer model: the JBL Xtreme 5, rated 4.6/5.
Pros: A rugged 2.1kg portable with IP67 protection, a replaceable battery, USB-C power-bank output, Auracast, stereo pairing and a useful 5-band app EQ. Independent reviews find the midrange detailed and the sound clear, punchy and refined for outdoor use; it also reaches a strong 106dB maximum level and has excellent real-world battery life.
Cons: It cannot produce the deep rumble of a larger speaker, and bass compression increases near maximum volume. The front-facing layout has only modest off-axis consistency, Bluetooth latency is high for video, and the default balance benefits from EQ adjustment. There is no aux input, so wired sources are not supported. Out of the box it leans bass-boosted, with a dip between the upper bass and midrange that EQ cannot fix, and it pushes the upper mids and treble at high volume. It is also expensive.
Full JBL Xtreme 4 review and specifications →
| Amplifier Power | 100W |
|---|---|
| App | Yes |
| Aux Input | No |
| Battery Life | 24 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Latency | 220ms |
| Bluetooth Version | 5.3 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 11.7” x 5.9” x 5.6” (297 x 149 x 141 mm) |
| Drivers | 2x 70mm woofers, 2x 19mm tweeters + 2x passive radiators |
| EQ | Yes (5 band) |
| Frequency Response | 44Hz - 20kHz (Manufacturer specified) |
| IP Rating | IP67 |
| Maximum SPL | 106dB (measured by Alan Ross Reviews) |
| Omnidirectional | No |
| Party Mode | Yes (Auracast) |
| Power Bank | Yes (USB-C) |
| Power Input | USB-C |
| Removable Battery | Yes |
| Stereo | Yes |
| Strap | Yes (detachable shoulder strap) |
| TWS | Yes |
| Weight | 4.6 lbs (2.1 kg) |
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