Short answer: the JBL Partybox Encore Essential 2. It ranks #5 of 75 boombox speakers by sound quality at $239; the Yeahbox Sonic Boom Ultra ranks #10 and costs $349.20, so there is not much of a tradeoff to weigh.
What the JBL Partybox Encore Essential 2 offers: 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. Watch for: 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.
What the Yeahbox Sonic Boom Ultra offers: By far the loudest boombox tested against it, hitting 106-107dB, roughly 3-5dB louder than the JBL Boombox 4, Zealot ZE41, Tribit Stormbox Blast 2, W-King X20, and Hopestar A90/A95. The massive 6x9in racetrack woofer reaches audible bass down to around 30Hz on the Country EQ preset, and a teardown confirmed genuinely robust internals: a thick vented voice coil and a dedicated crossover output per driver. HDMI ARC input/output lets it double as a TV soundbar, a feature none of its direct competitors offer. Watch for: The 500W peak-power rating doesn’t fully hold up: it gets noisy above roughly 80-90% volume, and the midrange isn’t fully refined, sometimes sitting a touch too forward. The custom EQ in the app noticeably reduces bass output compared to the factory presets and doesn’t persist after the speaker powers off. No Auracast, no removable battery, a plastic handle with some flex, and heavy at 11kg (24lb) for $388. Most of the sound-quality coverage comes from enthusiast listening-test comparisons rather than independent measurement.
Buy the JBL Partybox Encore Essential 2. It ranks higher for sound quality than the Yeahbox Sonic Boom Ultra and costs less, so the other one has nothing left to offer.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| JBL Partybox Encore Essential 2 | Yeahbox Sonic Boom Ultra | |
|---|---|---|
| Price | $239.00 | $349.20 |
| Ranked | #5 of 75 in Boombox Size Portable Bluetooth Speakers | #10 of 75 in Boombox Size Portable Bluetooth Speakers |
| App | Yes (JBL PartyBox app) | Yes |
| Aux Input | Yes | Yes |
| Battery Life | 15 hours (Manufacturer specified) | - |
| Built-in Microphone | No | - |
| EQ | Yes (7 band App EQ) | Yes (Country, Classic, and custom app EQ; custom settings don't persist after the app closes) |
| Guitar Input | Yes | - |
| IP Rating | IPX4 | IPX6 |
| Microphone Input | Yes (Karaoke mode with echo effect) | - |
| Party Mode | Yes (Auracast) | No (TWS stereo pairing of 2 units only, no Auracast) |
| Power Bank | Yes (USB-C) | - |
| Power Input | AC Power cord | USB-C (60W fast charging) |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| USB Playback | Yes | Yes |
| Weight | 13.7 lbs (6.2 kg) | 24.3 lbs (11 kg) |
| Wireless Microphones | No | - |
| Bluetooth Codecs | SBC | SBC (inferred; additional codecs unverified) |
| Bluetooth Version | 5.4 | 6.0 |
| Amplifier Power | 100W RMS | 320W RMS / 500W Peak |
| Dimensions | 12.6" x 13.5" x 10.3" (319.5 x 342 x 260.4 mm) | 23.4" x 9.8" x 12.3" (595 x 248 x 313 mm) |
| Drivers | 1x 135mm (5.25") woofer + 2x 20mm (0.75") dome tweeters | 6x9in racetrack woofer (200W) + 2x 4.5in midrange (40W each) + 2x tweeters (20W each), true 3-way |
| Maximum SPL | 110dB (measured by Alan Ross Reviews) | - |
| Digital Aux Input | No | No |
| Lights | Yes | Yes |
| Battery Capacity | - | 45000mAh (Reviewer estimated) |
| Inputs | - | HDMI ARC (in/out, usable as a TV soundbar), AUX in/out, USB drive, microSD, optional wired mic |
| MicroSD Playback | - | 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 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
JBL Partybox Encore Essential 2: $239.00 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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Yeahbox Sonic Boom Ultra: $349.20 Amazon eBay
Pros: By far the loudest boombox tested against it, hitting 106-107dB, roughly 3-5dB louder than the JBL Boombox 4, Zealot ZE41, Tribit Stormbox Blast 2, W-King X20, and Hopestar A90/A95. The massive 6x9in racetrack woofer reaches audible bass down to around 30Hz on the Country EQ preset, and a teardown confirmed genuinely robust internals: a thick vented voice coil and a dedicated crossover output per driver. HDMI ARC input/output lets it double as a TV soundbar, a feature none of its direct competitors offer.
Cons: The 500W peak-power rating doesn’t fully hold up: it gets noisy above roughly 80-90% volume, and the midrange isn’t fully refined, sometimes sitting a touch too forward. The custom EQ in the app noticeably reduces bass output compared to the factory presets and doesn’t persist after the speaker powers off. No Auracast, no removable battery, a plastic handle with some flex, and heavy at 11kg (24lb) for $388. Most of the sound-quality coverage comes from enthusiast listening-test comparisons rather than independent measurement.
Full Yeahbox Sonic Boom Ultra review and specifications →
| Amplifier Power | 320W RMS / 500W Peak |
|---|---|
| App | Yes |
| Aux Input | Yes |
| Battery Capacity | 45000mAh (Reviewer estimated) |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) |
| Bluetooth Version | 6.0 |
| Digital Aux Input | No |
| Dimensions | 23.4" x 9.8" x 12.3" (595 x 248 x 313 mm) |
| Drivers | 6x9in racetrack woofer (200W) + 2x 4.5in midrange (40W each) + 2x tweeters (20W each), true 3-way |
| EQ | Yes (Country, Classic, and custom app EQ; custom settings don't persist after the app closes) |
| IP Rating | IPX6 |
| Inputs | HDMI ARC (in/out, usable as a TV soundbar), AUX in/out, USB drive, microSD, optional wired mic |
| Lights | Yes |
| MicroSD Playback | Yes |
| Omnidirectional | No |
| Party Mode | No (TWS stereo pairing of 2 units only, no Auracast) |
| Power Input | USB-C (60W fast charging) |
| Stereo | Yes |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 24.3 lbs (11 kg) |
- Links
- Reviews, Comparisons and Sound Samples
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- Jagist reviews: Yeahbox Sonic Boom Ultra Bass Test!!! What A Beast!!! 😍😍😍
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