These sit in different size classes, so this is not a straight ranking comparison. The Teufel Rockster Cross ranks #23 of 120 large speakers by sound quality at $199.99; the Harman Kardon Onyx Studio 9 ranks #15 of 113 boombox speakers by sound quality at $184.99.
The Teufel Rockster Cross is the longer-running, lighter option. A splash resistant speaker with fairly neutral, vocal focused sound and punchy, controlled bass that suits rock and jazz. It is rated for 16 hours of battery against 8 for the Harman Kardon Onyx Studio 9. At 5.3 lbs (2.4 kg) it weighs much less than the Harman Kardon Onyx Studio 9 at 9.3 lbs (4.2 kg). It is rated IPX5, while the Harman Kardon Onyx Studio 9 has no water resistance. The catch: Outdoor mode can sound somewhat harsh due to the 4kHz peak.
The Harman Kardon Onyx Studio 9 is the deeper-bass pick. An elegant living room portable with balanced, smooth, non-fatiguing sound, app EQ, and stereo pairing for music lovers. Its bass reaches about 41Hz before falling 10dB, against 51Hz for the Teufel Rockster Cross. It links with other speakers (Auracast), which the Teufel Rockster Cross cannot. It has an adjustable EQ, which the Teufel Rockster Cross lacks. The tradeoff: It has no water resistance, aux input or USB playback, and its eight-hour claimed battery life is short for an outdoor portable.
Buy the Teufel Rockster Cross ($199.99) for a large speaker; the Harman Kardon Onyx Studio 9 ($184.99) suits a boombox speaker instead.
Looking for alternatives? See the complete Portable Bluetooth rankings.
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Specifications Side By Side
| Teufel Rockster Cross | Harman Kardon Onyx Studio 9 | |
|---|---|---|
| Price | $199.99 | $184.99 |
| Ranked | #23 of 120 in Large Size Portable Bluetooth Speakers | #15 of 113 in Boombox Size Portable Bluetooth Speakers |
| Aux Input | Yes | No |
| Bass Extension (-10dB) | 51Hz | 41Hz |
| Battery Life | 16 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| IP Rating | IPX5 | None |
| Power Input | DC barrel jack | AC Power Cable (2-Prong) |
| TWS | Yes | Yes |
| Weight | 5.3 lbs (2.4 kg) | 9.3 lbs (4.2 kg) |
| App | No | Yes (Harman Kardon One app) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, aptX | SBC |
| Built-in Microphone | Yes | - |
| EQ | No | Yes (App EQ) |
| Party Mode | No | Yes (Auracast) |
| Power Bank | Yes (USB-A) | - |
| Stereo | Partially | Yes |
| Omnidirectional | No | No |
| Bluetooth Version | 5.0 | 5.3 |
| Dimensions | 15” x 6.3” x 5.1” (380 x 160 x 130 mm) | 11.4” x 11.3” x 5.1” (289.2 x 287.5 x 130 mm) |
| Drivers | 5” woofer, 2x textile dome tweeters + 2x passive radiators | 120mm woofer + 3x 20mm tweeters |
| Frequency Response | 50Hz - 20kHz (Manufacturer specified) | - |
| Amplifier Power | 30W | 50W RMS |
| Digital Aux Input | No | No |
| Strap | Yes (detachable shoulder strap) | No |
| Maximum SPL | - | 101dB (measured by Alan Ross Reviews) |
| USB Playback | - | No |
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