Different classes, so treat this as a step-up-or-not question rather than a head-to-head. The Harman Kardon Onyx Studio 8 ranks #12 of 113 boombox speakers by sound quality at $199; the Zealot S79 ranks #52 of 120 large speakers by sound quality at $106.97.
These are built for different jobs. The Harman Kardon Onyx Studio 8 is a premium indoor design that sits well on furniture, while the Zealot S79 is rugged, loud and made to go outdoors.
In an indoor sound test listeners heard much deeper, cleaner bass from the Onyx Studio 8, with the Zealot a little louder but rougher. The Zealot’s bass boost mode can distort past about 70 percent volume.
The Zealot has the far bigger battery, a claimed 50+ hours against about 8, plus RGB lights, a shoulder strap and a power bank output. The Onyx is not water resistant, so it is a home speaker first.
Worth knowing: the Harman Kardon Onyx Studio 8 is discontinued, though it still ranks #12 of 113 boombox speakers by sound quality, so a used unit beats most of what is still sold new. The Harman Kardon Onyx Studio 8’s replacement, the Harman Kardon Onyx Studio 9, is rated 4.1/5 at $184.99.
Buy the Harman Kardon Onyx Studio 8 ($199) for a boombox speaker; the Zealot S79 ($106.97) suits a large speaker instead.
If water resistance matters to you, the Zealot S79 at IPX6 (powerful water jets) holds up far better than the Harman Kardon Onyx Studio 8 at no water resistance.
Want more options? Browse the full Portable Bluetooth rankings.
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Specifications Side By Side
| Harman Kardon Onyx Studio 8 | Zealot S79 | |
|---|---|---|
| Price | $199.00 Discontinued | $106.97 |
| Ranked | #12 of 113 in Boombox Size Portable Bluetooth Speakers | #52 of 120 in Large Size Portable Bluetooth Speakers |
| Aux Input | Yes | - |
| Aux Latency | 42ms | - |
| Bass Extension (-10dB) | 35Hz | - |
| Battery Life | 8 hours (Manufacturer specified) | 50+ hours (Manufacturer specified) |
| Built-in Microphone | Yes | - |
| IP Rating | None | IPX6 |
| Bluetooth Latency | 175ms | - |
| Maximum SPL | 96dB (measured by Alan Ross Reviews) | - |
| Power Input | DC Barrel Connector (19V/2.1A) | - |
| Stereo | Partially (1 woofer) | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 7.3 lbs (3.3 kg) | 7.3 lbs (3.3 kg) |
| App | Yes (Harman Kardon One app) | - |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | - |
| Power Bank | No | Yes |
| EQ | Yes (App EQ) | - |
| Party Mode | No | - |
| USB Playback | No | - |
| Bluetooth Version | 5.2 | 5.3 |
| Amplifier Power | 50W RMS | 100W (150W peak) |
| Dimensions | 10.6” x 11.9” x 6.3” (268 x 302.5 x 159.5 mm) | 13.4” x 7.2” x 5.7” (340 x 184 x 146 mm) |
| Drivers | 120mm woofer + 2x 20mm tweeters | 2 woofers + 2 tweeters |
| Digital Aux Input | No | - |
| Strap | No | Yes (detachable shoulder strap) |
| Lights | - | Yes |
Watch Them Compared
Videos and reviews that test both speakers side by side.
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