Harman Kardon Onyx Studio 9 vs W-King D20

Last updated: September 20, 2026

Short answer: the Onyx Studio 9 for balanced sound, the W-King D20 for karaoke. The D20 comes with 2 wireless microphones, but it has a rising frequency response with upper treble rolled off and 700Hz and 1.2kHz peaks. The Onyx Studio 9 adds Auracast multi-speaker connection alongside classic stereo pairing, though it has slightly recessed mids, a boost in the upper mids and rolled off upper treble.

Harman Kardon Onyx Studio 9 vs W-King D20

What the Harman Kardon Onyx Studio 9 gets right: Auracast multi-speaker connection alongside classic stereo pairing. The catch: Slight recessed mids, boost in the upper mids, rolled off upper treble.

On the W-King D20 side: Comes with 2 wireless microphones. The catch: Rising frequency response but upper treble rolled off, 700Hz and 1.2kHz peaks.

Buy the Harman Kardon Onyx Studio 9. It ranks higher for sound quality than the W-King D20 and costs less, so the other one has nothing left to offer.

There is a real battery-life gap here: the W-King D20 is rated for 24 hours, the Harman Kardon Onyx Studio 9 only 8 hours.

There is a real gap in water resistance: the W-King D20 at IPX6 (powerful water jets) against the Harman Kardon Onyx Studio 9, which has no water resistance.

Want more options? Browse the full Portable Bluetooth rankings.

Buy the Harman Kardon Onyx Studio 9 at Amazon ($189.99) →Buy the W-King D20 at Aliexpress ($193) →

Specifications Side By Side

Harman Kardon Onyx Studio 9 W-King D20
Price$189.99$193
Ranked#14 of 75 in Boombox Size Portable Bluetooth Speakers#29 of 75 in Boombox Size Portable Bluetooth Speakers
Bass Extension (-10dB)41Hz~42Hz
Maximum SPL101dB (measured by Alan Ross Reviews)112dB (measured by Alan Ross Reviews)
IP RatingNoneIPX6
Power InputAC Power Cable (2-Prong)USB-C
StereoYesYes
OmnidirectionalNoNo
TWSYesYes
Weight9.3 lbs (4.2 kg)14.3 lbs (6500 g)
AppYes (Harman Kardon One app)Yes (W-King app)
Bluetooth CodecsSBCSBC
EQYes (App EQ)Yes (App + button modes)
Party ModeYes (Auracast)No
USB PlaybackNoYes
Bluetooth Version5.35.3
Battery Life8 hours (Manufacturer specified)24 hours (Manufacturer specified)
Amplifier Power50W RMS200W
Dimensions11.4" x 11.3" x 5.1" (289.2 x 287.5 x 130 mm)19.9" x 8.5" x 10.6" (506 x 217 x 270 mm)
Drivers120mm woofer + 3x 20mm tweeters4.5" + 3.5" drivers + 1.2" tweeters
Digital Aux InputNoNo
Aux InputNoYes
MicroSD Playback-Yes
Wireless Microphones-Yes
Power Bank-Yes
Built-in Microphone-No
Buy the Harman Kardon Onyx Studio 9 at Amazon ($189.99) →Buy the W-King D20 at Aliexpress ($193) →

More worthwhile head-to-heads for Harman Kardon Onyx Studio 9:

Prices on this page were last checked September 22, 2026 at 5:11 AM 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 9: $189.99 Amazon eBay

Harman Kardon Onyx Studio 9 ranking card

Pros: An elegant 4.2kg living-room portable with a measured 41Hz -10dB bass point, 101dB maximum level, three tweeters, app EQ, stereo pairing and Auracast multi-speaker linking. Reviews praise its balanced, smooth presentation and non-fatiguing treble, making it a more music-focused choice than most party speakers. Measured bass extension of 41Hz (-10dB).

Cons: It has no water resistance, aux input or USB playback, and its eight-hour claimed battery life is short for an outdoor portable. Bass is less deep than some earlier Onyx Studio models, while the slightly recessed mids and rolled-off top end mean it is not the most open or detailed option; it still charges from an AC power cable rather than USB-C.

Full Harman Kardon Onyx Studio 9 review and specifications →

Amplifier Power50W RMS
AppYes (Harman Kardon One app)
Aux InputNo
Bass Extension (-10dB)41Hz
Battery Life8 hours (Manufacturer specified)
Bluetooth CodecsSBC
Bluetooth Version5.3
Digital Aux InputNo
Dimensions11.4" x 11.3" x 5.1" (289.2 x 287.5 x 130 mm)
Drivers120mm woofer + 3x 20mm tweeters
EQYes (App EQ)
IP RatingNone
Maximum SPL101dB (measured by Alan Ross Reviews)
OmnidirectionalNo
Party ModeYes (Auracast)
Power InputAC Power Cable (2-Prong)
StereoYes
TWSYes
USB PlaybackNo
Weight9.3 lbs (4.2 kg)
Check current price at Amazon ($189.99) →Search eBay for Harman Kardon Onyx Studio 9 →

W-King D20: $193 Aliexpress eBay

W-King D20 ranking card

Pros: Comes with 2 wireless microphones. Measured bass extension of ~42Hz (-10dB).

Cons: Rising frequency response but upper treble rolled off, 700Hz and 1.2kHz peaks

Full W-King D20 review and specifications →

Amplifier Power200W
AppYes (W-King app)
Aux InputYes
Bass Extension (-10dB)~42Hz
Battery Life24 hours (Manufacturer specified)
Bluetooth CodecsSBC
Bluetooth Version5.3
Built-in MicrophoneNo
Digital Aux InputNo
Dimensions19.9" x 8.5" x 10.6" (506 x 217 x 270 mm)
Drivers4.5" + 3.5" drivers + 1.2" tweeters
EQYes (App + button modes)
IP RatingIPX6
Maximum SPL112dB (measured by Alan Ross Reviews)
MicroSD PlaybackYes
OmnidirectionalNo
Party ModeNo
Power BankYes
Power InputUSB-C
StereoYes
TWSYes
USB PlaybackYes
Weight14.3 lbs (6500 g)
Wireless MicrophonesYes
Check current price at Aliexpress ($193) →Search eBay for W-King D20 →