Short answer: the Harman Kardon Onyx Studio 9. It ranks #15 of 113 boombox speakers by sound quality, rated 4.1/5, at $184.99; the Hopestar A90 ranks #22, rated 3.9/5, and costs $351.65, which makes this an easy call rather than a real tradeoff.
Why pick the Harman Kardon Onyx Studio 9: An elegant living room portable with balanced, smooth, non-fatiguing sound, app EQ, and stereo pairing for music lovers. It has an adjustable EQ, which the Hopestar A90 lacks. 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 Hopestar A90 is the tougher option. A huge, powerful boombox with deep bass, clear highs, a removable battery and a wireless microphone for big outdoor parties. It is rated IPX6, 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 catch: The JBL Partybox Encore Essential 2 was the better, more refined listen in a direct comparison.
Buy the Harman Kardon Onyx Studio 9. It is rated higher for sound quality than the Hopestar A90 and costs less, so only choose the other one for a particular feature it does better.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
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
| Harman Kardon Onyx Studio 9 | Hopestar A90 | |
|---|---|---|
| Price | $184.99 | $351.65 |
| Ranked | #15 of 113 in Boombox Size Portable Bluetooth Speakers | #22 of 113 in Boombox Size Portable Bluetooth Speakers |
| Bass Extension (-10dB) | 41Hz | - |
| Maximum SPL | 101dB (measured by Alan Ross Reviews) | - |
| IP Rating | None | IPX6 |
| Power Input | AC Power Cable (2-Prong) | - |
| Stereo | Yes | - |
| Omnidirectional | No | No |
| TWS | Yes | - |
| Weight | 9.3 lbs (4.2 kg) | - |
| App | Yes (Harman Kardon One app) | No |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | - |
| EQ | Yes (App EQ) | No |
| Party Mode | Yes (Auracast) | Yes (Auracast) |
| USB Playback | No | Yes |
| Bluetooth Version | 5.3 | 5.4 |
| Battery Life | 8 hours (Manufacturer specified) | 6-8 hours (Manufacturer specified) |
| Amplifier Power | 50W RMS | 700W |
| Dimensions | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) | 24.6” x 9.9” x 13.4” (624.5 x 252.5 x 341.5 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters | 2x 5” woofers + 2x 3.5” midranges + 2x 2.5” tweeters + 2x 2” ceramic tweeters |
| Digital Aux Input | No | - |
| Aux Input | No | Yes |
| Strap | No | - |
| Removable Battery | - | Yes |
| Frequency Response | - | 50Hz - 20kHz (Manufacturer specified) |
| MicroSD Playback | - | Yes |
| Wireless Microphones | - | Yes 1 Included |
| Lights | - | Yes |
Where the Ratings Come From
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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