Short answer: the JBL PartyBox On-The-Go 2 Plus. It ranks #5 of 113 boombox speakers by sound quality, rated 4.4/5, at $349.95. The Harman Kardon Onyx Studio 9 ranks #15, rated 4.1/5, at $184.99, $164.96 cheaper, not enough of a saving to outweigh the sound-quality gap.
The JBL PartyBox On-The-Go 2 Plus is the better-sounding, longer-running option. A well balanced karaoke party speaker with clean bass, clear vocals, on-board vocal removal, an included wireless mic and a removable battery. It is rated for 15 hours of battery against 8 for the Harman Kardon Onyx Studio 9. It is rated IPX4, 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: The bass has less kick and physical impact than the JBL Partybox Encore 2 or JBL Partybox Club 120, and the JBL Partybox Club 120 gets noticeably louder.
The Harman Kardon Onyx Studio 9 is the lighter option. 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 JBL PartyBox On-The-Go 2 Plus at 14.2 lbs (6.45 kg). The tradeoff: It has no water resistance, aux input or USB playback, and its eight-hour claimed battery life is short for an outdoor portable.
Buy the JBL PartyBox On-The-Go 2 Plus. It is rated higher for sound quality, and the $164.96 you would save on the Harman Kardon Onyx Studio 9 does not close the gap.
Want more options? Browse the full Portable Bluetooth rankings.
Prices on this page were last checked November 14, 2026 at 6:17 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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Specifications Side By Side
| JBL PartyBox On-The-Go 2 Plus | Harman Kardon Onyx Studio 9 | |
|---|---|---|
| Price | $349.95 | $184.99 |
| Ranked | #5 of 113 in Boombox Size Portable Bluetooth Speakers | #15 of 113 in Boombox Size Portable Bluetooth Speakers |
| App | Yes (JBL One app) | Yes (Harman Kardon One app) |
| Aux Input | Yes | No |
| Battery Life | 15 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| Built-in Microphone | No | - |
| EQ | Yes (app EQ, Deep and Punchy bass boost) | Yes (App EQ) |
| IP Rating | IPX4 | None |
| Party Mode | Yes (Auracast) | Yes (Auracast) |
| Power Bank | Yes (USB-C, 11V/2A) | - |
| Power Input | AC Power cord | AC Power Cable (2-Prong) |
| Removable Battery | Yes | - |
| Stereo | Partially | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| USB Playback | Yes | No |
| Weight | 14.2 lbs (6.45 kg) | 9.3 lbs (4.2 kg) |
| Wireless Microphones | Yes 1 Included | - |
| Microphone Input | No (wireless only) | - |
| Guitar Input | No | - |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, LC3 | SBC |
| Bluetooth Version | 5.4 | 5.3 |
| Amplifier Power | 100W RMS | 50W RMS |
| Dimensions | 19.7” x 10.2” x 8.7” (501 x 258 x 221 mm) | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) |
| Drivers | 1x 135mm (5.25”) woofer + 2x 20mm (0.75”) dome tweeters | 120mm woofer + 3x 20mm tweeters |
| Frequency Response | 40Hz - 20kHz (-6dB, Manufacturer specified) | - |
| Digital Aux Input | Yes (USB-C) | No |
| Lights | Yes | - |
| Strap | Yes (detachable shoulder strap) | No |
| Bass Extension (-10dB) | - | 41Hz |
| Maximum SPL | - | 101dB (measured by Alan Ross Reviews) |
Where the Ratings Come From
- JBL PartyBox On-The-Go 2 Plus: reviews by GYMCADDY and Peter Tyson Audio & Visual.
- Harman Kardon Onyx Studio 9: reviews by Alan Ross.
This comparison is generated from the ratings, specifications and measurements on each product’s own page, and it updates when that data changes. How we rank explains how each rating is decided.
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