These sit in different size classes, so this is not a straight ranking comparison. The Bose SoundLink Plus ranks #25 of 82 large speakers by sound quality at $269; the Harman Kardon Onyx Studio 9 ranks #15 of 76 boombox speakers by sound quality at $189.99.
What the Bose SoundLink Plus does well: IP67 rated, IP67 water/dustproof. The catch: Boosted thuddy bass, but not as deep as the SoundLink Flex and you should probably just buy one of those instead if you want a Bose.
The case for the Harman Kardon Onyx Studio 9: An elegant 4.2kg living-room portable with a measured 41Hz -10dB bass point, 101dB maximum level, three tweeters, app EQ, stereo pairing and Auracast multi-speaker linking. 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 Bose SoundLink Plus at $269 for a large speaker, or the Harman Kardon Onyx Studio 9 at $189.99 for a boombox speaker instead.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Bose SoundLink Plus | Harman Kardon Onyx Studio 9 | |
|---|---|---|
| Price | $269.00 | $189.99 |
| Ranked | #25 of 82 in Large Size Portable Bluetooth Speakers | #15 of 76 in Boombox Size Portable Bluetooth Speakers |
| App | Yes | Yes (Harman Kardon One app) |
| Aux Input | No | No |
| Battery Life | 20 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| Built-in Microphone | No | - |
| IP Rating | IP67 | None |
| Party Mode | Yes (Bose Party mode) | Yes (Auracast) |
| Power Bank | Yes (USB-C) | - |
| Power Input | USB-C | AC Power Cable (2-Prong) |
| TWS | Yes | Yes |
| Weight | 3.3 lbs (1.5 kg) | 9.3 lbs (4.2 kg) |
| Bluetooth Codecs | SBC | SBC |
| EQ | No | Yes (App EQ) |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| Bluetooth Version | 5.4 | 5.3 |
| Dimensions | 9.1” x 3.9” x 3.4” (231 x 99 x 86 mm) | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) |
| Drivers | 1x 2.5” (63.5mm) woofer + 1x ~0.78” (20mm) tweeter + 4x passive radiators | 120mm woofer + 3x 20mm tweeters |
| Digital Aux Input | No | No |
| Strap | Yes (built-in loop) | No |
| Bass Extension (-10dB) | - | 41Hz |
| Maximum SPL | - | 101dB (measured by Alan Ross Reviews) |
| USB Playback | - | No |
| Amplifier Power | - | 50W RMS |
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- Earfun Uboom X vs Harman Kardon Onyx Studio 9
- Harman Kardon Onyx Studio 9 vs Tribit Stormbox Blast
- Harman Kardon Go + Play 3 vs Harman Kardon Onyx Studio 9
- JBL Partybox Encore 2 vs Harman Kardon Onyx Studio 9
- Harman Kardon Onyx Studio 9 vs JBL Partybox Encore Essential 2
Prices on this page were last checked September 26, 2026 at 11:14 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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The Two Speakers In Full
Bose SoundLink Plus: $269.00 Amazon eBay
Pros: IP67 rated, IP67 water/dustproof. Close to 20 hour battery life. Vibrant sound with booming bass, clean mids. Bluetooth 5.4 with good range. Premium tactile grille, smooth silicone. Quality build at $269.
Cons: Boosted thuddy bass, but not as deep as the SoundLink Flex and you should probably just buy one of those instead if you want a Bose.
Full Bose SoundLink Plus review and specifications →
| App | Yes |
|---|---|
| Aux Input | No |
| Battery Life | 20 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.4 |
| Built-in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 9.1” x 3.9” x 3.4” (231 x 99 x 86 mm) |
| Drivers | 1x 2.5” (63.5mm) woofer + 1x ~0.78” (20mm) tweeter + 4x passive radiators |
| EQ | No |
| IP Rating | IP67 |
| Omnidirectional | No |
| Party Mode | Yes (Bose Party mode) |
| Power Bank | Yes (USB-C) |
| Power Input | USB-C |
| Stereo | Yes |
| Strap | Yes (built-in loop) |
| TWS | Yes |
| Weight | 3.3 lbs (1.5 kg) |
- Links
- Reviews, Comparisons and Sound Samples
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Harman Kardon Onyx Studio 9: $189.99 Amazon eBay
Older models: the Harman Kardon Onyx Studio 8 (rated 4.1/5), the Harman Kardon Onyx Studio 7 (rated 4.1/5), the Harman Kardon Onyx Studio 6 (rated 4.1/5), the Harman Kardon Onyx Studio 5 (rated 3.9/5) and the Harman Kardon Onyx Studio 4 (rated 3.3/5).
Pros: An elegant 4.2kg living-room portable with a measured 41Hz -10dB bass point, 101dB maximum level, three tweeters, app EQ, stereo pairing and Auracast multi-speaker linking. Reviews praise its balanced, smooth presentation and non-fatiguing treble, making it a more music-focused choice than most party speakers. Measured bass extension of 41Hz (-10dB).
Cons: It has no water resistance, aux input or USB playback, and its eight-hour claimed battery life is short for an outdoor portable. Bass is less deep than some earlier Onyx Studio models, while the slightly recessed mids and rolled-off top end mean it is not the most open or detailed option; it still charges from an AC power cable rather than USB-C.
Full Harman Kardon Onyx Studio 9 review and specifications →
| Amplifier Power | 50W RMS |
|---|---|
| App | Yes (Harman Kardon One app) |
| Aux Input | No |
| Bass Extension (-10dB) | 41Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| Digital Aux Input | No |
| Dimensions | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters |
| EQ | Yes (App EQ) |
| IP Rating | None |
| Maximum SPL | 101dB (measured by Alan Ross Reviews) |
| Omnidirectional | No |
| Party Mode | Yes (Auracast) |
| Power Input | AC Power Cable (2-Prong) |
| Stereo | Yes |
| Strap | No |
| TWS | Yes |
| USB Playback | No |
| Weight | 9.3 lbs (4.2 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Harman Kardon Onyx Studio 9 vs Harman Kardon Onyx Studio 7
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