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 Onn Large Party gen 2 ranks #17 of 53 party speakers by sound quality at $129.
Different sizes. The Onyx Studio 9 is a 9.3 lbs (4.2 kg) boombox size speaker. The Onn Large Party gen 2 is a 20.9 lbs (9.5 kg) party speaker on wheels. Each is rated within its own class.
The Onyx Studio 9 is balanced and smooth with bass to about 41Hz and non-fatiguing treble. It has no water rating and a claimed 8 hours.
The Onn Large Party gen 2 has real bass impact and enough output for a large room, plus FM radio, mic and guitar inputs and wheels. Its mids are hazy and its treble smeared, and it has no EQ.
Buy the Harman Kardon Onyx Studio 9 at $184.99 for a boombox speaker, or the Onn Large Party gen 2 at $129 for a party speaker instead.
There is a real gap in water resistance: the Onn Large Party gen 2 at IPX4 (splashing) against the Harman Kardon Onyx Studio 9, which has no water resistance.
Want more options? Browse the full Portable Bluetooth rankings.
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Specifications Side By Side
| Harman Kardon Onyx Studio 9 | Onn Large Party gen 2 | |
|---|---|---|
| Price | $184.99 | $129 |
| Ranked | #15 of 113 in Boombox Size Portable Bluetooth Speakers | #17 of 53 in Party Size Portable Bluetooth Speakers |
| Bass Extension (-10dB) | 41Hz | - |
| Maximum SPL | 101dB (measured by Alan Ross Reviews) | - |
| IP Rating | None | IPX4 |
| Power Input | AC Power Cable (2-Prong) | AC Power cord |
| Stereo | Yes | Partially |
| Omnidirectional | No | No |
| TWS | Yes | No |
| Weight | 9.3 lbs (4.2 kg) | 20.9 lbs (9.5 kg) |
| App | Yes (Harman Kardon One app) | No |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| EQ | Yes (App EQ) | No |
| Party Mode | Yes (Auracast) | Yes (Party Sync Mode) |
| USB Playback | No | No |
| Bluetooth Version | 5.3 | - |
| Battery Life | 8 hours (Manufacturer specified) | 12 hours (Manufacturer specified) |
| Amplifier Power | 50W RMS | 160W RMS (640W peak) |
| Dimensions | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) | 22.5”H x 11.6”W x 11.8”D (571 x 295 x 300 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters | Dual 8” (203mm) woofers + dual tweeters |
| Digital Aux Input | No | No |
| Aux Input | No | Yes |
| Strap | No | No |
| FM Tuner | - | Yes |
| Guitar Input | - | Yes |
| Microphone Input | - | Yes (Karaoke mode with echo effect) |
| Power Bank | - | Yes (USB-A, 5V/2.1A) |
| Lights | - | Yes |
| Wheels | - | Yes |
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