Short answer: the Yeahbox Sonic Boom Ultra. It ranks #11 of 112 boombox speakers by sound quality, rated 4.2/5, at $388. The Harman Kardon Onyx Studio 7 ranks #14, rated 4.1/5, at $248.90, $139.10 cheaper, a saving that is not big enough to make up the sound-quality gap.
The Yeahbox Sonic Boom Ultra is the longer-running, tougher choice. 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 8 for the Harman Kardon Onyx Studio 7. It is rated IPX6, while the Harman Kardon Onyx Studio 7 has no water resistance. It has an adjustable EQ, which the Harman Kardon Onyx Studio 7 lacks. The tradeoff: 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 Harman Kardon Onyx Studio 7 is the lighter choice. An elegant home portable with warm, spacious sound, strong deep bass, and stereo pairing with a second unit. At 6.4 lbs (2.9 kg) it weighs much less than the Yeahbox Sonic Boom Ultra at 24.3 lbs (11 kg). It links with other speakers (Wireless Dual Sound), which the Yeahbox Sonic Boom Ultra cannot. Watch for: Consumer Reports finds the bass prominent and boomy, mids hazy, treble slightly smeared and the soundstage congested.
Buy the Yeahbox Sonic Boom Ultra. It is rated higher for sound quality, and saving $139.10 with the Harman Kardon Onyx Studio 7 does not make up for the sound-quality gap.
Looking for alternatives? See the complete Portable Bluetooth rankings.
A massively loud boombox with deep bass, long battery life, and HDMI ARC so it can double as a TV soundbar.
An elegant home portable with warm, spacious sound, strong deep bass, and stereo pairing with a second unit.
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Specifications Side By Side
| Yeahbox Sonic Boom Ultra | Harman Kardon Onyx Studio 7 | |
|---|---|---|
| Price | $388.00 | $248.90 |
| Ranked | #11 of 112 in Boombox Size Portable Bluetooth Speakers | #14 of 112 in Boombox Size Portable Bluetooth Speakers |
| App | Yes | No |
| Aux Input | Yes | Yes |
| Battery Capacity | 45000mAh (Reviewer estimated) | - |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 6.0 | 4.2 |
| Dimensions | 23.4” x 9.8” x 12.3” (595 x 248 x 313 mm) | 11.3” x 11.3” (285.8 x 285.8 mm) (round design) |
| Drivers | 6x9in racetrack woofer (200W) + 2x 4.5in midrange (40W each) + 2x tweeters (20W each), true 3-way | 120mm woofer + 2x 25mm tweeters |
| EQ | Yes (Country, Classic, and custom app EQ; custom settings don’t persist after the app closes) | No |
| Inputs | HDMI ARC (in/out, usable as a TV soundbar), AUX in/out, USB drive, microSD, optional wired mic | - |
| IP Rating | IPX6 | None |
| MicroSD Playback | Yes | - |
| Amplifier Power | 320W RMS / 500W Peak | 50W RMS |
| Party Mode | No (TWS stereo pairing of 2 units only, no Auracast) | Yes (Wireless Dual Sound) |
| Power Input | USB-C (60W fast charging) | DC Barrel Connector (19V/2.1A) |
| Stereo | Yes | Partially (1 woofer) |
| Omnidirectional | No | No |
| TWS | Yes | No |
| USB Playback | Yes | No |
| Weight | 24.3 lbs (11 kg) | 6.4 lbs (2.9 kg) |
| Digital Aux Input | No | No |
| Bluetooth Codecs | SBC (inferred; additional codecs unverified) | SBC |
| Lights | Yes | - |
| Battery Life | 24 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| Strap | No | No |
| Aux Latency | - | 0ms |
| Bass Extension (-10dB) | - | 37Hz |
| Built-in Microphone | - | Yes |
| Bluetooth Latency | - | 266ms |
| Maximum SPL | - | 96dB (measured by Alan Ross Reviews) |
| Power Bank | - | No |
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