Short answer: the Onyx Studio 9 for connectivity and price, the JBL Authentics 300 for built-in voice assistants. The Authentics 300 integrates Amazon Alexa and Google Assistant simultaneously, rare for smart speakers, but it is narrow sounding with bass not as deep as others, peaky upper mids and no TWS. The Onyx Studio 9 adds Auracast and an EQ-capable app, though it has slightly recessed mids and rolled off upper treble.
The case for the Harman Kardon Onyx Studio 9: Auracast multi-speaker connection alongside classic stereo pairing. Harman Kardon One app with EQ. Watch for: Slight recessed mids, boost in the upper mids, rolled off upper treble.
Buy the Harman Kardon Onyx Studio 9. It is rated higher for sound quality than the JBL Authentics 300 and costs less, so only choose the other one for a particular feature it does better.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Harman Kardon Onyx Studio 9 | JBL Authentics 300 | |
|---|---|---|
| Price | $189.99 | $299.95 |
| Ranked | #15 of 90 in Boombox Size Portable Bluetooth Speakers | #41 of 90 in Boombox Size Portable Bluetooth Speakers |
| Bass Extension (-10dB) | 41Hz | 45Hz |
| Maximum SPL | 101dB (measured by Alan Ross Reviews) | 100dB (measured by Alan Ross Reviews) |
| IP Rating | None | None |
| Power Input | AC Power Cable (2-Prong) | AC Power cable |
| Stereo | Yes | Partially (1 woofer) |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 9.3 lbs (4.2 kg) | 10.8 lbs (4.9 kg) |
| App | Yes (Harman Kardon One app) | Yes |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| EQ | Yes (App EQ) | Yes (App EQ) |
| Party Mode | Yes (Auracast) | Yes (Wi-Fi Multi-Room) |
| USB Playback | No | Yes |
| Bluetooth Version | 5.3 | 5.3 |
| Battery Life | 8 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| Amplifier Power | 50W RMS | 100W |
| Dimensions | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) | 13.5” x 7.7” x 7.1” (342 x 195.6 x 180.3 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters | 1” tweeter + 4” woofer + passive radiators |
| Digital Aux Input | No | No |
| Aux Input | No | No |
| Strap | No | No |
| Wi-Fi | - | Yes |
| Power Bank | - | No |
| Built-in Microphone | - | Yes |
| MicroSD Playback | - | No |
| Voice Assistants | - | Amazon Alexa & Google Assistant (simultaneous) |
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Prices on this page were last checked October 3, 2026 at 10:26 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
Harman Kardon Onyx Studio 9: $189.99 Amazon eBay
Older models: the Harman Kardon Onyx Studio 8 (ranked higher, rated 4.1/5), the Harman Kardon Onyx Studio 7 (ranked higher, rated 4.1/5), the Harman Kardon Onyx Studio 6 (ranked higher, rated 4.1/5), the Harman Kardon Onyx Studio 5 (ranked lower, 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 | Yes |
| 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
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JBL Authentics 300: $299.95 Amazon eBay
Pros: Integrates both Amazon Alexa and Google Assistant simultaneously (rare for smart speakers). Retro seventies design with leather and Quadrex grille. 100-watt amp, carries well with leather-trimmed handle. Rechargeable battery rated ~8 hours. Measured bass extension of 45Hz (-10dB).
Cons: Narrow sounding, bass not as deep as others. Peaky upper mids. No TWS. No IP rating. Not as loud as others. Not much battery life.
Full JBL Authentics 300 review and specifications →
| Amplifier Power | 100W |
|---|---|
| App | Yes |
| Aux Input | No |
| Bass Extension (-10dB) | 45Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 13.5” x 7.7” x 7.1” (342 x 195.6 x 180.3 mm) |
| Drivers | 1” tweeter + 4” woofer + passive radiators |
| EQ | Yes (App EQ) |
| IP Rating | None |
| Maximum SPL | 100dB (measured by Alan Ross Reviews) |
| MicroSD Playback | No |
| Omnidirectional | No |
| Party Mode | Yes (Wi-Fi Multi-Room) |
| Power Bank | No |
| Power Input | AC Power cable |
| Stereo | Partially (1 woofer) |
| Strap | No |
| TWS | Yes |
| USB Playback | Yes |
| Voice Assistants | Amazon Alexa & Google Assistant (simultaneous) |
| Weight | 10.8 lbs (4.9 kg) |
| Wi-Fi | Yes |
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- Reviews, Comparisons and Sound Samples
- JOY‘s 🎧3D🔈Audio-Show: JBL Authentics 300 - sound quality test More from Oluv’Sone →
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- Alan Ross Reviews: Not quite! JBL Authentics 300 review and sound test vs Boombox 3, Encore and Stormbox Blast More from alanrossreviews →
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