Harman Kardon Onyx Studio 7 vs Demerbox DB2

Last updated: September 16, 2026

Short answer: the Harman Kardon Onyx Studio 7. It ranks #13 of 75 boombox speakers by sound quality at $248.90; the Demerbox DB2 ranks #51 and costs $400, which makes this an easy call rather than a real tradeoff.

Harman Kardon Onyx Studio 7 vs Demerbox DB2

What the Harman Kardon Onyx Studio 7 offers: The addition of dual tweeters gives the Studio 7 a wider, more spacious presentation than older Onyx models. It delivers strong, deep bass, useful large-room volume and can pair with a second Studio 7 for stereo. Watch for: Consumer Reports finds the bass prominent and boomy, mids hazy, treble slightly smeared and the soundstage congested. Battery life remains only about eight hours, it has no water rating or advanced codecs, and it is not an especially loud outdoor speaker.

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 7. It ranks higher for sound quality than the Demerbox DB2 and costs less, so the other one has nothing left to offer.

If battery life is a priority, the Demerbox DB2 is rated for 40 hours versus 8 hours for the Harman Kardon Onyx Studio 7.

Water resistance is not close: the Demerbox DB2 is rated at IP67 (brief submersion), well ahead of the Harman Kardon Onyx Studio 7 at no water resistance.

Want more options? Browse the full Portable Bluetooth rankings.

Buy the Harman Kardon Onyx Studio 7 at Amazon ($248.90) →Buy the Demerbox DB2 at Amazon ($400) →

Specifications Side By Side

Harman Kardon Onyx Studio 7 Demerbox DB2
Price$248.90$400
Ranked#13 of 75 in Boombox Size Portable Bluetooth Speakers#51 of 75 in Boombox Size Portable Bluetooth Speakers
Aux InputYesYes
Aux Latency0ms-
Bass Extension (-10dB)37Hz-
Battery Life8 hours (Manufacturer specified)40 hours (Manufacturer specified)
Built-in MicrophoneYesNo
IP RatingNoneIP67
Bluetooth Latency266ms-
Maximum SPL96dB (measured by Alan Ross Reviews)-
Party ModeYes (Wireless Dual Sound)No
Power InputDC Barrel Connector (19V/2.1A)AC Power brick
StereoPartially (1 woofer)Yes
OmnidirectionalNoNo
TWSNoYes
Weight6.4 lbs (2.9 kg)5.4 lbs (2.47 kg)
Bluetooth CodecsSBCSBC
AppNoNo
EQNoNo
Power BankNoYes (USB-A + USB-C)
USB PlaybackNoNo
Amplifier Power50W RMS22W RMS
Dimensions11.3" x 11.3" (285.8 x 285.8 mm) (round design)10.6" x 9.7" x 6.9" (270 x 246 x 175 mm)
Drivers2x 75mm woofers + 2x 20mm tweeters2x 3" (76mm) aluminum cone full-range drivers
Digital Aux InputNoNo
FM Tuner-No
Buy the Harman Kardon Onyx Studio 7 at Amazon ($248.90) →Buy the Demerbox DB2 at Amazon ($400) →

How Harman Kardon Onyx Studio 7 compares with other leading options:

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 7: $248.90 Amazon eBay

Harman Kardon Onyx Studio 7 ranking card

Pros: The addition of dual tweeters gives the Studio 7 a wider, more spacious presentation than older Onyx models. It delivers strong, deep bass, useful large-room volume and can pair with a second Studio 7 for stereo. Measured bass extension of 37Hz (-10dB).

Cons: Consumer Reports finds the bass prominent and boomy, mids hazy, treble slightly smeared and the soundstage congested. Battery life remains only about eight hours, it has no water rating or advanced codecs, and it is not an especially loud outdoor speaker.

Full Harman Kardon Onyx Studio 7 review and specifications →

Amplifier Power50W RMS
AppNo
Aux InputYes
Aux Latency0ms
Bass Extension (-10dB)37Hz
Battery Life8 hours (Manufacturer specified)
Bluetooth CodecsSBC
Bluetooth Latency266ms
Built-in MicrophoneYes
Digital Aux InputNo
Dimensions11.3" x 11.3" (285.8 x 285.8 mm) (round design)
Drivers2x 75mm woofers + 2x 20mm tweeters
EQNo
IP RatingNone
Maximum SPL96dB (measured by Alan Ross Reviews)
OmnidirectionalNo
Party ModeYes (Wireless Dual Sound)
Power BankNo
Power InputDC Barrel Connector (19V/2.1A)
StereoPartially (1 woofer)
TWSNo
USB PlaybackNo
Weight6.4 lbs (2.9 kg)
Check current price at Amazon ($248.90) →Search eBay for Harman Kardon Onyx Studio 7 →

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 →