Different classes, so treat this as a step-up-or-not question rather than a head-to-head. The Harman Kardon Onyx Studio 9 ranks #15 of 113 boombox speakers by sound quality at $184.99; the Soundboks Rider ranks #31 of 53 party speakers by sound quality at $599.
The Harman Kardon Onyx Studio 9 is the 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 noticeably less than the Soundboks Rider at 14.3 lbs (6.5 kg). It links with other speakers (Auracast), which the Soundboks Rider cannot. It plays in stereo from a single unit, unlike the Soundboks Rider. 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 Soundboks Rider is the longer-running, tougher pick. A light, rugged party speaker with a swappable battery that lasts all day at mid volume and an app with a six band EQ. It is rated for 35 hours of battery against 8 for the Harman Kardon Onyx Studio 9. It is rated IP66, 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: Its sealed 8in woofer runs out of real bass at high volume: Xander measured the -6 dB point rising to roughly 75 to 85 Hz at maximum, with 40 Hz some 20 dB down, and M1M heard the bass pulled back toward the upper bass above mid volume.
Buy the Harman Kardon Onyx Studio 9 ($184.99) for a boombox speaker; the Soundboks Rider ($599) suits a party speaker instead.
Looking for alternatives? See the complete Portable Bluetooth rankings.
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Specifications Side By Side
| Harman Kardon Onyx Studio 9 | Soundboks Rider | |
|---|---|---|
| Price | $184.99 | $599.00 |
| Ranked | #15 of 113 in Boombox Size Portable Bluetooth Speakers | #31 of 53 in Party Size Portable Bluetooth Speakers |
| Bass Extension (-10dB) | 41Hz | - |
| Maximum SPL | 101dB (measured by Alan Ross Reviews) | 113.2dB(C) (measured by M1M Tech Channel) |
| IP Rating | None | IP66 |
| Power Input | AC Power Cable (2-Prong) | USB-C (65W fast charging) |
| Stereo | Yes | No |
| Omnidirectional | No | No |
| TWS | Yes | No |
| Weight | 9.3 lbs (4.2 kg) | 14.3 lbs (6.5 kg) |
| App | Yes (Harman Kardon One app) | Yes (Soundboks) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | - |
| EQ | Yes (App EQ) | Yes (6-band EQ + Bass+, Indoor and Outdoor profiles) |
| Party Mode | Yes (Auracast) | No (no TeamUp) |
| USB Playback | No | - |
| Bluetooth Version | 5.3 | - |
| Battery Life | 8 hours (Manufacturer specified) | 35 hours (Manufacturer specified) |
| Amplifier Power | 50W RMS | 92W RMS (72W woofer + 20W tweeter) |
| Dimensions | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) | - |
| Drivers | 120mm woofer + 3x 20mm tweeters | 8” woofer (sealed), 1.2” dome tweeter in horn |
| Digital Aux Input | No | No |
| Aux Input | No | Yes |
| Strap | No | No |
| Frequency Response | - | 40Hz - 20kHz (Manufacturer specified) |
| Removable Battery | - | Yes |
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