Short answer: the Harman Kardon Onyx Studio 9. It ranks #14 of 75 boombox speakers by sound quality at $194.95; the Bumpboxx Flare 6 ranks #58 and costs $300, so there is not much of a tradeoff to weigh.
What the Harman Kardon Onyx Studio 9 offers: 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. Watch for: 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.
What the Bumpboxx Flare 6 offers: At 5.9 kg, Bumpboxx Flare 6 combines 6” woofer + tweeters with Bluetooth. Claimed 12 hours (manufacturer specified) battery life, ipx6 protection, up to 115db and stereo playback make its feature set practical for its intended room or portable use. Watch for: There is no companion app. No EQ adjustment.
Buy the Harman Kardon Onyx Studio 9. It ranks higher for sound quality than the Bumpboxx Flare 6 and costs less, so there is no real case for the other one.
Skip the Bumpboxx Flare 6 if sound quality matters to you. It ranks near the bottom of the 75 boombox speakers.
If water resistance matters to you, the Bumpboxx Flare 6 at IPX6 (powerful water jets) holds up far better than the Harman Kardon Onyx Studio 9 at no water resistance.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| Harman Kardon Onyx Studio 9 | Bumpboxx Flare 6 | |
|---|---|---|
| Price | $194.95 | $300 |
| Ranked | #14 of 75 in Boombox Size Portable Bluetooth Speakers | #58 of 75 in Boombox Size Portable Bluetooth Speakers |
| Bass Extension (-10dB) | 41Hz | - |
| Maximum SPL | 101dB (measured by Alan Ross Reviews) | 115dB (Manufacturer specified) |
| IP Rating | None | IPX6 |
| Power Input | AC Power Cable (2-Prong) | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 9.3 lbs (4.2 kg) | 13 lbs (5.9 kg) |
| App | Yes (Harman Kardon One app) | No |
| Bluetooth Codecs | SBC | SBC |
| EQ | Yes (App EQ) | No |
| Party Mode | Yes (Auracast) | No |
| USB Playback | No | No |
| Bluetooth Version | 5.3 | - |
| Battery Life | 8 hours (Manufacturer specified) | 12 hours (Manufacturer specified) |
| Amplifier Power | 50W RMS | 150W |
| Dimensions | 11.4" x 11.3" x 5.1" (289.2 x 287.5 x 130 mm) | 24" x 6" x 14" (609.6 x 152.4 x 355.6 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters | 6" woofer + tweeters |
| Digital Aux Input | No | No |
| Power Bank | - | No |
| Built-in Microphone | - | No |
| FM Tuner | - | Yes |
| Lights | - | Yes |
Related Speaker Comparisons
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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 16, 2026 at 12:41 AM 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
Harman Kardon Onyx Studio 9: $194.95 Amazon eBay
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) |
| 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 |
| TWS | Yes |
| USB Playback | No |
| Weight | 9.3 lbs (4.2 kg) |
- Links
- Reviews, Comparisons and Sound Samples
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Bumpboxx Flare 6: $300 eBay
Pros: At 5.9 kg, Bumpboxx Flare 6 combines 6” woofer + tweeters with Bluetooth. Claimed 12 hours (manufacturer specified) battery life, ipx6 protection, up to 115db and stereo playback make its feature set practical for its intended room or portable use.
Cons: There is no companion app. No EQ adjustment.
Full Bumpboxx Flare 6 review and specifications →
| Amplifier Power | 150W |
|---|---|
| App | No |
| Battery Life | 12 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Built-in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 24" x 6" x 14" (609.6 x 152.4 x 355.6 mm) |
| Drivers | 6" woofer + tweeters |
| EQ | No |
| FM Tuner | Yes |
| IP Rating | IPX6 |
| Lights | Yes |
| Maximum SPL | 115dB (Manufacturer specified) |
| Omnidirectional | No |
| Party Mode | No |
| Power Bank | No |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| USB Playback | No |
| Weight | 13 lbs (5.9 kg) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons