Short answer: the Onyx Studio 9 for features and battery, the JBL Partybox Encore Essential for party sound. The Encore Essential is a great-sounding, somewhat bass-boosted party speaker, but it runs only 6 hours of battery at medium volume and has a poor water rating. The Onyx Studio 9 adds Auracast multi-speaker connection, USB-C charging and an EQ-capable app for less money, though it has slightly recessed mids and rolled-off upper treble.
Buy the JBL Partybox Encore Essential. It is rated higher for sound quality, and the $114.96 saving on the Harman Kardon Onyx Studio 9 is not enough to make up the difference.
Water resistance is not close: the JBL Partybox Encore Essential is rated at IPX4 (splashing), well ahead of the Harman Kardon Onyx Studio 9 at no water resistance.
Looking for alternatives? See the complete Portable Bluetooth rankings.
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Specifications Side By Side
| Harman Kardon Onyx Studio 9 | JBL Partybox Encore Essential | |
|---|---|---|
| Price | $184.99 | $299.95 |
| Ranked | #15 of 113 in Boombox Size Portable Bluetooth Speakers | #8 of 113 in Boombox Size Portable Bluetooth Speakers |
| Bass Extension (-10dB) | 41Hz | 38Hz |
| 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 lbs (5.9 kg) |
| App | Yes (Harman Kardon One app) | Yes (JBL PartyBox app) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| EQ | Yes (App EQ) | Yes (3 band App EQ) |
| Party Mode | Yes (Auracast) | Yes (PartyBoost up to 100 speakers) |
| USB Playback | No | Yes |
| Bluetooth Version | 5.3 | 5.1 |
| Battery Life | 8 hours (Manufacturer specified) | 6 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) | 10.9” x 12.9” x 11.5” (276 x 327 x 293 mm) |
| Drivers | 120mm woofer + 3x 20mm tweeters | 135mm woofer + 2x 44mm tweeters |
| Digital Aux Input | No | No |
| Aux Input | No | Yes |
| Strap | No | No |
| Aux Latency | - | 17ms |
| Built-in Microphone | - | No |
| Bluetooth Latency | - | 100ms |
| Power Bank | - | Yes (USB-A, 5V/0.5A) |
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