Short answer: the JBL PartyBox On-The-Go 2 Plus. It ranks #5 of 89 boombox speakers by sound quality, rated 4.4/5, at $349.95. The Harman Kardon Onyx Studio 9 ranks #15, rated 4.1/5, at $189.99, $159.96 cheaper, not enough of a saving to outweigh the sound-quality gap.
What the JBL PartyBox On-The-Go 2 Plus does well: Well balanced with strong vocals, and its front-firing bass ports give it cleaner, smoother bass than other PartyBoxes, so even the Punchy bass boost setting never overpowers the vocals. The catch: The bass has less kick and physical impact than the Encore 2 or PartyBox Club 120, and the Club 120 gets noticeably louder.
What the Harman Kardon Onyx Studio 9 does well: 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 catch: 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 JBL PartyBox On-The-Go 2 Plus. It is rated higher for sound quality, and the $159.96 you would save on the Harman Kardon Onyx Studio 9 does not close the gap.
Water resistance is not close: the JBL PartyBox On-The-Go 2 Plus is rated at IPX4 (splashing), well ahead of the Harman Kardon Onyx Studio 9 at no water resistance.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| JBL PartyBox On-The-Go 2 Plus | Harman Kardon Onyx Studio 9 | |
|---|---|---|
| Price | $349.95 | $189.99 |
| Ranked | #5 of 89 in Boombox Size Portable Bluetooth Speakers | #15 of 89 in Boombox Size Portable Bluetooth Speakers |
| App | Yes (JBL One app) | Yes (Harman Kardon One app) |
| Aux Input | Yes | No |
| Battery Life | 15 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| Built-in Microphone | No | - |
| EQ | Yes (app EQ, Deep and Punchy bass boost) | Yes (App EQ) |
| IP Rating | IPX4 | None |
| Party Mode | Yes (Auracast) | Yes (Auracast) |
| Power Bank | Yes (USB-C, 11V/2A) | - |
| Power Input | AC Power cord | AC Power Cable (2-Prong) |
| Removable Battery | Yes | - |
| Stereo | Partially | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| USB Playback | Yes | No |
| Weight | 14.2 lbs (6.45 kg) | 9.3 lbs (4.2 kg) |
| Wireless Microphones | Yes 1 Included | - |
| Microphone Input | No (wireless only) | - |
| Guitar Input | No | - |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, LC3 | SBC |
| Bluetooth Version | 5.4 | 5.3 |
| Amplifier Power | 100W RMS | 50W RMS |
| Dimensions | 19.7” x 10.2” x 8.7” (501 x 258 x 221 mm) | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) |
| Drivers | 1x 135mm (5.25”) woofer + 2x 20mm (0.75”) dome tweeters | 120mm woofer + 3x 20mm tweeters |
| Frequency Response | 40Hz - 20kHz (-6dB, Manufacturer specified) | - |
| Digital Aux Input | Yes (USB-C) | No |
| Lights | Yes | - |
| Strap | Yes (detachable shoulder strap) | No |
| Bass Extension (-10dB) | - | 41Hz |
| Maximum SPL | - | 101dB (measured by Alan Ross Reviews) |
Related Speaker Comparisons
More worthwhile head-to-heads for JBL PartyBox On-The-Go 2 Plus:
- Tribit Stormbox Blast vs JBL PartyBox On-The-Go 2 Plus
- JBL Partybox Encore 2 vs JBL PartyBox On-The-Go 2 Plus
- JBL PartyBox On-The-Go 2 Plus vs JBL Partybox Encore Essential 2
- JBL PartyBox On-The-Go 2 Plus vs JBL Partybox Encore Essential
- JBL PartyBox On-The-Go 2 Plus vs Harman Kardon Onyx Studio 8
Prices on this page were last checked September 30, 2026 at 2:57 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
JBL PartyBox On-The-Go 2 Plus: $349.95 Amazon eBay
Older model: the JBL Partybox On the Go (ranked lower, rated 3/5).
Pros: Well balanced with strong vocals, and its front-firing bass ports give it cleaner, smoother bass than other PartyBoxes, so even the Punchy bass boost setting never overpowers the vocals. It gets a touch louder than the PartyBox Encore 2. EasySing AI vocal removal strips vocals from any song on the speaker itself, with 25%, 50% or 100% removal, and the included rechargeable wireless mic has a tight pickup pattern that rejects handling noise. A removable 34Wh battery shared with the Encore 2 and PartyBox 120, a claimed 15 hours, a padded shoulder strap, USB-C playback and charging, a 3.5mm aux input, Auracast and a light show.
Cons: The bass has less kick and physical impact than the Encore 2 or PartyBox Club 120, and the Club 120 gets noticeably louder. There is no wired microphone or guitar input, so more mics means buying JBL’s EasySing mics separately, and AI vocal removal is disabled while the speaker is linked to other speakers over Auracast. Real world battery life is closer to 7 hours at 80% volume with lights and bass boost on. IPX4 only covers splashes, the grille dents easily, and the battery must be installed for it to run even when plugged in.
Full JBL PartyBox On-The-Go 2 Plus review and specifications →
| Amplifier Power | 100W RMS |
|---|---|
| App | Yes (JBL One app) |
| Aux Input | Yes |
| Battery Life | 15 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC, LC3 |
| Bluetooth Version | 5.4 |
| Built-in Microphone | No |
| Digital Aux Input | Yes (USB-C) |
| Dimensions | 19.7” x 10.2” x 8.7” (501 x 258 x 221 mm) |
| Drivers | 1x 135mm (5.25”) woofer + 2x 20mm (0.75”) dome tweeters |
| EQ | Yes (app EQ, Deep and Punchy bass boost) |
| Frequency Response | 40Hz - 20kHz (-6dB, Manufacturer specified) |
| Guitar Input | No |
| IP Rating | IPX4 |
| Lights | Yes |
| Microphone Input | No (wireless only) |
| Omnidirectional | No |
| Party Mode | Yes (Auracast) |
| Power Bank | Yes (USB-C, 11V/2A) |
| Power Input | AC Power cord |
| Removable Battery | Yes |
| Stereo | Partially |
| Strap | Yes (detachable shoulder strap) |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 14.2 lbs (6.45 kg) |
| Wireless Microphones | Yes 1 Included |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- JBL PartyBox On-The-Go 2 Plus vs JBL Partybox Encore 2
- JBL PartyBox On-The-Go 2 Plus vs JBL Partybox Encore Essential 2
- JBL PartyBox On-The-Go 2 Plus vs JBL Partybox Encore Essential
- JBL PartyBox On-The-Go 2 Plus vs Tribit Stormbox Blast
- JBL PartyBox On-The-Go 2 Plus vs Harman Kardon Onyx Studio 8
- JBL PartyBox On-The-Go 2 Plus vs Zealot ZE51
- JBL PartyBox On-The-Go 2 Plus vs Zealot ZE41
- JBL PartyBox On-The-Go 2 Plus vs Zealot ZE21
- See all 25 comparisons
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
- Head-to-Head Comparisons
- Harman Kardon Onyx Studio 9 vs Harman Kardon Onyx Studio 7
- Harman Kardon Onyx Studio 9 vs Zealot ZE51
- Harman Kardon Onyx Studio 9 vs Zealot ZE41
- Harman Kardon Onyx Studio 9 vs Harman Kardon Onyx Studio 6
- Harman Kardon Onyx Studio 9 vs Zealot ZE21
- Harman Kardon Onyx Studio 9 vs Harman Kardon Onyx Studio 8
- Harman Kardon Onyx Studio 9 vs Zealot S89
- Harman Kardon Onyx Studio 9 vs Yeahbox Sonic Boom Ultra
- See all 93 comparisons