Short answer: the W-King D9, if you are buying new. The Harman Kardon Onyx Studio 4 ranks higher than it (#67 vs #91 of 105 large speakers, 3.3/5 vs 2.5/5) but is discontinued, so only consider it used; the W-King D9 is still sold new at $71.24. The Harman Kardon Onyx Studio 4’s replacement, the Harman Kardon Onyx Studio 9, is still sold new.
The Harman Kardon Onyx Studio 4 is the better-sounding pick. Balanced sound quality with deep resonant bass and crisp treble, large dynamic range. It links with other speakers (Connect+ up to 100 speakers), which the W-King D9 cannot. The tradeoff: 8 hour battery at medium volume.
The W-King D9 is the longer-running, tougher pick. A compact 4.4 lbs (2 kg) boombox with 60W RMS output, a claimed 106dB maximum level, a measured 47Hz -10dB bass point, IPX6 protection, power-bank output, USB-C charging, aux and microSD playback. It is rated for 40 hours of battery against 8 for the Harman Kardon Onyx Studio 4. It is rated IPX6, while the Harman Kardon Onyx Studio 4 has no water resistance. The catch: Treble rolls off early, limiting air and fine detail, while owner reports note Bluetooth interference and some noise at maximum speaker volume.
Buy the W-King D9 if you want one new; the Harman Kardon Onyx Studio 4 is discontinued, so only look for it used.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Harman Kardon Onyx Studio 4 | W-King D9 | |
|---|---|---|
| Price | $100 Discontinued | $71.24 |
| Ranked | #67 of 105 in Large Size Portable Bluetooth Speakers | #91 of 105 in Large Size Portable Bluetooth Speakers |
| App | Yes (HK Connect) | No |
| Aux Input | Yes | Yes |
| Battery Life | 8 hours (Manufacturer specified) | 40 hours (Manufacturer specified) |
| EQ | No | No |
| IP Rating | None | IPX6 |
| Party Mode | Yes (Connect+ up to 100 speakers) | No |
| Power Bank | No | Yes (USB-A) |
| TWS | Yes | No |
| Weight | 4.5 lbs (2.06 kg) | 4.4 lbs (2.0 kg) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| Built-in Microphone | Yes | Yes |
| Power Input | DC Barrel Connector (19V/2.1A) | USB-C |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| Bluetooth Version | 4.2 | 5.3 |
| Drivers | 2x 75mm woofers + 2x 20mm tweeters + 1x passive radiator | 2x 40mm drivers + passive radiators |
| Dimensions | 11.4” x 11.4” x 5.1” (290 x 290 x 130 mm) | 4.7” x 12.4” x 4.7” (120 x 315 x 120 mm) |
| Frequency Response | 50Hz - 20kHz (Manufacturer specified) | 80Hz - 16kHz (Manufacturer specified) |
| Amplifier Power | 60W | 60W RMS |
| Digital Aux Input | No | No |
| Strap | No | No |
| Bass Extension (-10dB) | - | 47Hz |
| Maximum SPL | - | 106dB (measured by Alan Ross Reviews) |
| MicroSD Playback | - | Yes |
Related Speaker Comparisons
More worthwhile head-to-heads for Harman Kardon Onyx Studio 4:
- JBL Xtreme 5 vs Harman Kardon Onyx Studio 4
- Tribit Stormbox Lava vs Harman Kardon Onyx Studio 4
- Soundcore Boom 2 vs Harman Kardon Onyx Studio 4
- Marshall Stockwell II vs Harman Kardon Onyx Studio 4
- Harman Kardon Citation 200 vs Harman Kardon Onyx Studio 4
Prices on this page were last checked October 12, 2026 at 4:13 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Speakers In Full
Harman Kardon Onyx Studio 4: $100 Discontinued eBay
Newer model: the Harman Kardon Onyx Studio 9, rated 4.1/5, released Dec 2024. See every Harman Kardon Onyx Studio generation.
Pros: Balanced sound quality with deep resonant bass and crisp treble, large dynamic range. Multi-host Bluetooth connectivity for 2 phones, daisy chaining up to 100 speakers. Elegant modern design with smooth curves and premium materials.
Cons: 8 hour battery at medium volume. Not at loud as others. Not as deep of bass as the newer Onyx. External AC power brick for charging. Discontinued.
Full Harman Kardon Onyx Studio 4 review and specifications →
| Released | Aug 2017 (9 years ago) |
|---|---|
| Amplifier Power | 60W |
| App | Yes (HK Connect) |
| Aux Input | Yes |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 4.2 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 11.4” x 11.4” x 5.1” (290 x 290 x 130 mm) |
| Drivers | 2x 75mm woofers + 2x 20mm tweeters + 1x passive radiator |
| EQ | No |
| Frequency Response | 50Hz - 20kHz (Manufacturer specified) |
| IP Rating | None |
| Omnidirectional | No |
| Party Mode | Yes (Connect+ up to 100 speakers) |
| Power Bank | No |
| Power Input | DC Barrel Connector (19V/2.1A) |
| Stereo | Yes |
| Strap | No |
| TWS | Yes |
| Weight | 4.5 lbs (2.06 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Harman Kardon Onyx Studio 4 vs Tronsmart Halo 100
- Harman Kardon Onyx Studio 4 vs Zealot S97
- Harman Kardon Onyx Studio 4 vs JBL Xtreme
- Harman Kardon Onyx Studio 4 vs JBL Xtreme 2
- Harman Kardon Onyx Studio 4 vs DOSS Soundbox XL
- Harman Kardon Onyx Studio 4 vs Klipsch Detroit
- Harman Kardon Onyx Studio 4 vs Sony SRS-XG300
- Harman Kardon Onyx Studio 4 vs W-King D8
- See all 47 comparisons
W-King D9: $71.24 Amazon $71.24 eBay
Pros: A compact 2kg boombox with 60W RMS output, a claimed 106dB maximum level, a measured 47Hz -10dB bass point, IPX6 protection, power-bank output, USB-C charging, aux and microSD playback. Long-term owners praise its loud, punchy character and useful indoor/outdoor voicing for casual outdoor listening. Measured bass extension of 47Hz (-10dB).
Cons: Treble rolls off early, limiting air and fine detail, while owner reports note Bluetooth interference and some noise at maximum speaker volume. There is no app or adjustable EQ, and its bass does not reach as deep as larger rivals, so it is better suited to energetic background music than neutral listening.
Full W-King D9 review and specifications →
| Released | Dec 2020 (5 years ago) |
|---|---|
| Amplifier Power | 60W RMS |
| App | No |
| Aux Input | Yes |
| Bass Extension (-10dB) | 47Hz |
| Battery Life | 40 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 4.7” x 12.4” x 4.7” (120 x 315 x 120 mm) |
| Drivers | 2x 40mm drivers + passive radiators |
| EQ | No |
| Frequency Response | 80Hz - 16kHz (Manufacturer specified) |
| IP Rating | IPX6 |
| Maximum SPL | 106dB (measured by Alan Ross Reviews) |
| MicroSD Playback | Yes |
| Omnidirectional | No |
| Party Mode | No |
| Power Bank | Yes (USB-A) |
| Power Input | USB-C |
| Stereo | Yes |
| Strap | No |
| TWS | No |
| Weight | 4.4 lbs (2.0 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons