Short answer: the JBL Partybox Encore Essential 2 for off-axis performance, the Onyx Studio 9 for connectivity. The Encore Essential 2 appears to have better off axis performance due to the move to dome tweeters over cone, though it is missing a little bit of upper bass. The Onyx Studio 9 adds Auracast multi-speaker connection alongside classic stereo pairing, but has slightly recessed mids, a boost in the upper mids and rolled off upper treble.
What the Harman Kardon Onyx Studio 9 gets right: Auracast multi-speaker connection alongside classic stereo pairing. The tradeoff: Slight recessed mids, boost in the upper mids, rolled off upper treble.
On the JBL Partybox Encore Essential 2 side: Appears to have better off axis performance due to the move to dome tweeters over cone. The tradeoff: Missing a little bit of upper bass.
Buy the JBL Partybox Encore Essential 2. It is rated higher for sound quality, and saving $64.13 with the Harman Kardon Onyx Studio 9 does not make up for the sound-quality gap.
If battery life is a priority, the JBL Partybox Encore Essential 2 is rated for 15 hours versus 8 hours for the Harman Kardon Onyx Studio 9.
There is a real gap in water resistance: the JBL Partybox Encore Essential 2 at IPX4 (splashing) against the Harman Kardon Onyx Studio 9, which has no water resistance.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| Harman Kardon Onyx Studio 9 | JBL Partybox Encore Essential 2 | |
|---|---|---|
| Price | $189.99 | $254.12 |
| Ranked | #14 of 75 in Boombox Size Portable Bluetooth Speakers | #5 of 75 in Boombox Size Portable Bluetooth Speakers |
| Bass Extension (-10dB) | 41Hz | - |
| Maximum SPL | 101dB (measured by Alan Ross Reviews) | 110dB (measured by Alan Ross Reviews) |
| IP Rating | None | IPX4 |
| Power Input | AC Power Cable (2-Prong) | AC Power cord |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 9.3 lbs (4.2 kg) | 13.7 lbs (6.2 kg) |
| App | Yes (Harman Kardon One app) | Yes (JBL PartyBox app) |
| Bluetooth Codecs | SBC | SBC |
| EQ | Yes (App EQ) | Yes (7 band App EQ) |
| Party Mode | Yes (Auracast) | Yes (Auracast) |
| USB Playback | No | Yes |
| Bluetooth Version | 5.3 | 5.4 |
| Battery Life | 8 hours (Manufacturer specified) | 15 hours (Manufacturer specified) |
| Amplifier Power | 50W RMS | 100W RMS |
| Dimensions | 11.4" x 11.3" x 5.1" (289.2 x 287.5 x 130 mm) | 12.6" x 13.5" x 10.3" (319.5 x 342 x 260.4 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters | 1x 135mm (5.25") woofer + 2x 20mm (0.75") dome tweeters |
| Digital Aux Input | No | No |
| Aux Input | No | Yes |
| Built-in Microphone | - | No |
| Guitar Input | - | Yes |
| Microphone Input | - | Yes (Karaoke mode with echo effect) |
| Power Bank | - | Yes (USB-C) |
| Wireless Microphones | - | No |
| Lights | - | Yes |
Related Speaker Comparisons
How JBL Partybox Encore Essential 2 compares with other leading options:
- Earfun Uboom X vs JBL Partybox Encore Essential 2
- JBL Partybox Encore Essential 2 vs Tribit Stormbox Blast
- Harman Kardon Go + Play 3 vs JBL Partybox Encore Essential 2
- JBL Partybox Encore 2 vs JBL Partybox Encore Essential 2
- JBL Partybox Encore vs JBL Partybox Encore Essential 2
Prices on this page were last checked September 23, 2026 at 11:24 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
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 |
| TWS | Yes |
| USB Playback | No |
| Weight | 9.3 lbs (4.2 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
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JBL Partybox Encore Essential 2: $254.12 Amazon B&H Photo Video eBay
Pros: A compact 6.2kg party speaker with 100W output, 110dB maximum level, a 15-hour claimed battery, app-based 7-band EQ, dynamic lighting, USB playback, guitar and mic inputs, and Auracast linking. Independent testing finds a balanced midrange, genuinely punchy low bass and enough output for a backyard gathering; its dome tweeters also improve the earlier Encore’s high-frequency behavior.
Cons: It is front-facing, so the sound changes noticeably to the sides and behind it, and bass compression reduces kick-drum impact at maximum volume. Bluetooth latency can cause lip-sync issues, its IPX4 rating only covers splashes, and it omits the wireless microphones bundled with the non-Essential Encore 2.
Full JBL Partybox Encore Essential 2 review and specifications →
| Amplifier Power | 100W RMS |
|---|---|
| App | Yes (JBL PartyBox app) |
| Aux Input | Yes |
| Battery Life | 15 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.4 |
| Built-in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 12.6" x 13.5" x 10.3" (319.5 x 342 x 260.4 mm) |
| Drivers | 1x 135mm (5.25") woofer + 2x 20mm (0.75") dome tweeters |
| EQ | Yes (7 band App EQ) |
| Guitar Input | Yes |
| IP Rating | IPX4 |
| Lights | Yes |
| Maximum SPL | 110dB (measured by Alan Ross Reviews) |
| Microphone Input | Yes (Karaoke mode with echo effect) |
| Omnidirectional | No |
| Party Mode | Yes (Auracast) |
| Power Bank | Yes (USB-C) |
| Power Input | AC Power cord |
| Stereo | Yes |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 13.7 lbs (6.2 kg) |
| Wireless Microphones | No |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- JBL Partybox Encore Essential 2 vs JBL Partybox Encore
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- JBL Partybox Encore Essential 2 vs Tribit Stormbox Blast
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