These sit in different size classes, so this is not a straight ranking comparison. The JBL Partybox Stage 320 ranks #3 of 53 party speakers by sound quality at $569.95; the Yeahbox Sonic Boom Ultra ranks #11 of 113 boombox speakers by sound quality at $388.
Different sizes. The Stage 320 is a 36.4 lbs (16.5 kg) party speaker on wheels. The Sonic Boom Ultra is an 24.3 lbs (11 kg) boombox. Each is rated within its own class.
The Sonic Boom Ultra was the loudest boombox in comparison tests and reaches audible bass near 30Hz on its Country preset. HDMI ARC lets it double as a TV soundbar. It gets noisy above about 80 to 90% volume, its custom EQ reduces bass, and it lacks Auracast and a removable battery.
The Stage 320 keeps more bass at high volume than the PartyBox 310, has wheels, a removable battery with a claimed 18 hours, mic and guitar inputs, Auracast and a light show. It can get a little sibilant at full blast.
Weather: the Yeahbox is IPX6 against the Stage 320’s IPX4.
Buy the JBL Partybox Stage 320 at $569.95 for a party speaker, or the Yeahbox Sonic Boom Ultra at $388 for a boombox speaker instead.
Want more options? Browse the full Portable Bluetooth rankings.
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Specifications Side By Side
| JBL Partybox Stage 320 | Yeahbox Sonic Boom Ultra | |
|---|---|---|
| Price | $569.95 | $388.00 |
| Ranked | #3 of 53 in Party Size Portable Bluetooth Speakers | #11 of 113 in Boombox Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Aux Input | Yes | Yes |
| Battery Life | 18 hours (Manufacturer specified) | 24 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC (inferred; additional codecs unverified) |
| Bluetooth Version | 5.4 | 6.0 |
| Drivers | 2x 6.5” woofers, 2x 25mm tweeters | 6x9in racetrack woofer (200W) + 2x 4.5in midrange (40W each) + 2x tweeters (20W each), true 3-way |
| EQ | Yes (5 band) | 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-A, 5V/2.1A) | - |
| Power Input | AC Power cord | USB-C (60W fast charging) |
| Removable Battery | Yes | - |
| Stereo | Partially | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| USB Playback | Yes | Yes |
| Weight | 36.4 lbs (16.5 kg) | 24.3 lbs (11 kg) |
| Amplifier Power | 240W | 320W RMS / 500W Peak |
| Digital Aux Input | No | No |
| Lights | Yes | Yes |
| Wheels | Yes | - |
| Dimensions | 26.3”H x 13.2”W x 15.2”D (669 x 335 x 385 mm) | 23.4” x 9.8” x 12.3” (595 x 248 x 313 mm) |
| Strap | No | No |
| 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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