Short answer: the Harman Kardon Onyx Studio 9. It ranks #15 of 112 boombox speakers by sound quality, rated 4.1/5, at $184.99; the EcoXGear Defender ranks #84, rated 2.5/5, and costs $299.99, which makes this an easy call rather than a real tradeoff.
The Harman Kardon Onyx Studio 9 is the better-sounding choice. An elegant living room portable with balanced, smooth, non-fatiguing sound, app EQ, and stereo pairing for music lovers. It links with other speakers (Auracast), which the EcoXGear Defender cannot. It plays in stereo from a single unit, unlike the EcoXGear Defender. 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 EcoXGear Defender is the longer-running, tougher option. A rugged, floating waterproof speaker that gets very loud for its size, with a flashlight, bottle opener and power bank. It is rated for 25 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. Watch for: Its single front-facing driver layout has narrow dispersion: clarity and detail drop noticeably when you move off-axis, and the soundstage is limited.
Buy the Harman Kardon Onyx Studio 9. It is rated higher for sound quality than the EcoXGear Defender and costs less, so it is the default pick unless a specific strength of the other one matters more to you.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
An elegant living room portable with balanced, smooth, non-fatiguing sound, app EQ, and stereo pairing for music lovers.
A rugged, floating waterproof speaker that gets very loud for its size, with a flashlight, bottle opener and power bank.
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Specifications Side By Side
| Harman Kardon Onyx Studio 9 | EcoXGear Defender | |
|---|---|---|
| Price | $184.99 | $299.99 |
| Ranked | #15 of 112 in Boombox Size Portable Bluetooth Speakers | #84 of 112 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) | USB-C |
| Stereo | Yes | No |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 9.3 lbs (4.2 kg) | 10 lbs (4.54 kg) |
| App | Yes (Harman Kardon One app) | No |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| EQ | Yes (App EQ) | Yes |
| Party Mode | Yes (Auracast) | No |
| USB Playback | No | No |
| Bluetooth Version | 5.3 | 5.1 |
| Battery Life | 8 hours (Manufacturer specified) | 25 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) | 6.7” x 15.4” x 9.6” (170.2 x 391.2 x 243.8 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters | 52mm full-range driver |
| Digital Aux Input | No | No |
| Aux Input | No | Yes |
| Strap | No | No |
| Power Bank | - | Yes (USB-C, 5V/2.1A) |
| Built-in Microphone | - | Yes |
| FM Tuner | - | No |
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