Short answer: the JBL Partybox Encore Essential 2. It ranks #6 of 112 boombox speakers by sound quality, rated 4.3/5, at $249.95; the Yeahbox Sonic Boom Ultra ranks #11, rated 4.2/5, and costs $388, so there is not much of a tradeoff to weigh.
The JBL Partybox Encore Essential 2 is the lighter option. A compact party speaker with balanced sound, punchy bass, mic and guitar inputs, and enough volume for a backyard party. At 13.7 lbs (6.2 kg) it weighs much less than the Yeahbox Sonic Boom Ultra at 24.3 lbs (11 kg). It links with other speakers (Auracast), which the Yeahbox Sonic Boom Ultra cannot. The catch: 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.
The Yeahbox Sonic Boom Ultra is the longer-running, tougher pick. A massively loud boombox with deep bass, long battery life, and HDMI ARC so it can double as a TV soundbar. It is rated for 24 hours of battery against 15 for the JBL Partybox Encore Essential 2. It is rated IPX6 against IPX4 for the JBL Partybox Encore Essential 2. The catch: 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.
Buy the JBL Partybox Encore Essential 2. It is rated higher for sound quality than the Yeahbox Sonic Boom Ultra and costs less, which makes it the one to get unless you need something the other one does better.
Want more options? Browse the full Portable Bluetooth rankings.
A compact party speaker with balanced sound, punchy bass, mic and guitar inputs, and enough volume for a backyard party.
A massively loud boombox with deep bass, long battery life, and HDMI ARC so it can double as a TV soundbar.
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Specifications Side By Side
| JBL Partybox Encore Essential 2 | Yeahbox Sonic Boom Ultra | |
|---|---|---|
| Price | $249.95 | $388.00 |
| Ranked | #6 of 112 in Boombox Size Portable Bluetooth Speakers | #11 of 112 in Boombox Size Portable Bluetooth Speakers |
| App | Yes (JBL PartyBox app) | Yes |
| Aux Input | Yes | Yes |
| Battery Life | 15 hours (Manufacturer specified) | 24 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 | Yes | Yes |
| 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 |
| Strap | No | No |
| Bass Extension (-10dB) | 42Hz | - |
| 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 |
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