Harman Kardon Onyx Studio 9 vs Demerbox DB2

Last updated: September 16, 2026

Short answer: the Harman Kardon Onyx Studio 9. It ranks #14 of 75 boombox speakers by sound quality at $194.95; the Demerbox DB2 ranks #51 and costs $400, which makes this an easy call rather than a real tradeoff.

Harman Kardon Onyx Studio 9 vs Demerbox DB2

What the Harman Kardon Onyx Studio 9 offers: 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. Watch for: 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.

What the Demerbox DB2 offers: 40+ hour battery life even at higher volumes (real-world: ~14 hrs with phone charging mixed in). Built from a Pelican case - nearly indestructible and waterproof (IP67). Multi-pair up to 6 units. Doubles as power bank and waterproof container. Watch for: Bass is not as deep as better speakers. Very overpriced.

Buy the Harman Kardon Onyx Studio 9. It ranks higher for sound quality than the Demerbox DB2 and costs less, so the other one has nothing left to offer.

Battery life favors the Demerbox DB2: rated for 40 hours against 8 hours for the Harman Kardon Onyx Studio 9.

Water resistance is not close: the Demerbox DB2 is rated at IP67 (brief submersion), well ahead of the Harman Kardon Onyx Studio 9 at no water resistance.

Still deciding? The full Portable Bluetooth rankings cover every ranked option.

Buy the Harman Kardon Onyx Studio 9 at Amazon ($194.95) →Buy the Demerbox DB2 at Amazon ($400) →

Specifications Side By Side

Harman Kardon Onyx Studio 9 Demerbox DB2
Price$194.95$400
Ranked#14 of 75 in Boombox Size Portable Bluetooth Speakers#51 of 75 in Boombox Size Portable Bluetooth Speakers
Bass Extension (-10dB)41Hz-
Maximum SPL101dB (measured by Alan Ross Reviews)-
IP RatingNoneIP67
Power InputAC Power Cable (2-Prong)AC Power brick
StereoYesYes
OmnidirectionalNoNo
TWSYesYes
Weight9.3 lbs (4.2 kg)5.4 lbs (2.47 kg)
AppYes (Harman Kardon One app)No
Bluetooth CodecsSBCSBC
EQYes (App EQ)No
Party ModeYes (Auracast)No
USB PlaybackNoNo
Bluetooth Version5.3-
Battery Life8 hours (Manufacturer specified)40 hours (Manufacturer specified)
Amplifier Power50W RMS22W RMS
Dimensions11.4" x 11.3" x 5.1" (289.2 x 287.5 x 130 mm)10.6" x 9.7" x 6.9" (270 x 246 x 175 mm)
Drivers120mm woofer + 3x 20mm tweeters2x 3" (76mm) aluminum cone full-range drivers
Digital Aux InputNoNo
Aux Input-Yes
Power Bank-Yes (USB-A + USB-C)
Built-in Microphone-No
FM Tuner-No
Buy the Harman Kardon Onyx Studio 9 at Amazon ($194.95) →Buy the Demerbox DB2 at Amazon ($400) →

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

Prices on this page were last checked September 16, 2026 at 12:41 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: $194.95 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)
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 ($194.95) →Search eBay for Harman Kardon Onyx Studio 9 →

Demerbox DB2: $400 Amazon eBay

Demerbox DB2 ranking card

Pros: 40+ hour battery life even at higher volumes (real-world: ~14 hrs with phone charging mixed in). Built from a Pelican case - nearly indestructible and waterproof (IP67). Multi-pair up to 6 units. Doubles as power bank and waterproof container.

Cons: Bass is not as deep as better speakers. Very overpriced.

Full Demerbox DB2 review and specifications →

Amplifier Power22W RMS
AppNo
Aux InputYes
Battery Life40 hours (Manufacturer specified)
Bluetooth CodecsSBC
Built-in MicrophoneNo
Digital Aux InputNo
Dimensions10.6" x 9.7" x 6.9" (270 x 246 x 175 mm)
Drivers2x 3" (76mm) aluminum cone full-range drivers
EQNo
FM TunerNo
IP RatingIP67
OmnidirectionalNo
Party ModeNo
Power BankYes (USB-A + USB-C)
Power InputAC Power brick
StereoYes
TWSYes
USB PlaybackNo
Weight5.4 lbs (2.47 kg)
Check current price at Amazon ($400) →Search eBay for Demerbox DB2 →