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The Onyx also incorporates a built-in, rechargeable battery that's rated for eight hours of playback on a single charge – plenty for a backyard barbeque or working in the garage. Holding the power button for about one second indicates battery levels by lighting up a corresponding number of dots along the volume strip.
Set-up and connectivity
As with most wireless speakers, the Harman Kardon Onyx requires a bit of set up. The good news is that it's fairly intuitive for simple Bluetooth streaming. The unit quickly connected to an iPad and Samsung Galaxy phone by pressing and holding the Bluetooth key on the speaker, and then pairing via the device settings.
However, the Onyx offers a little more than the typical Bluetooth speaker in terms of connectivity by allowing users to stream audio via Wi-Fi using AirPlay (for iOS) and DNLA (for Android and others). Though, this feature definitely requires cracking open the manual.
You can pair the speaker to your home network in one of two ways. If your router is equipped with a WPS button, you can press it and then press the corresponding button on the Onyx. Or, if you have an iOS device that is connected both via Bluetooth to the speaker and to your Wi-Fi network, you can press the Wi-Fi indicator key on the top edge of the speaker until you see a notification prompting you to share settings.
Once successfully connected to the network, the speaker's Wi-Fi indicator light shines solid white. Unfortunately, while I was able to pair the Onyx with the network, getting any music to stream over Wi-Fi was another challenge, and one that isn't addressed in the manual. I ended up calling customer support, but to no avail. The representative stated that I could have a dysfunctional unit, or it could be an issue with the home network.
Harman Kardon also offers a free Remote app, which is designed for use with the whole suite of the company's products. Its usefulness with the Onyx is quite limited: you can control volume, activate the stereo widening feature and view the remaining battery life. Theoretically, you can also toggle between audio sources (AirPlay, DLNA and Bluetooth), though I didn't have any success rate with that functionality due to the aforementioned Wi-Fi issues.
Sound
While the Wi-Fi streaming experience was frustrating, the Onyx's overall performance is impressive. Provided I remained in the standard Bluetooth range, I observed no dropouts when playing music from various devices. Better still, it delivers a pleasant soundspace across a variety of genres, from rock and folk to hip-hop and electronic music.
Thanks to its two woofers, bass is incredibly thumpy – although, realistically, the precise characteristics of the low-end depend on what type of surface you place the speaker on. Wood provides the best overall sound; I could actually feel the bass in my feet when the unit was placed on a wooden table on top of a wood deck.
And then, of course, there's the volume: the Onyx gets loud. Loud enough to rock a raucous house party or, in my case, completely drown out the freeway beyond our deck. For most songs, the speaker maintains great sound quality at high volumes, though I recommend standing at least a few feet back when it's cranked up all the way.
We Liked
The Harman Kardon Onyx comes to the table with a stylish, durable design and simple, reliable Bluetooth streaming capability. Add to that thumping bass and impressive volume levels, and you have a party-friendly speaker for both indoors and out.
We Disliked
That said, $500 is a lot to spend on a speaker, especially one with questionable Wi-Fi connectivity. Also, we'd like to see Harman Kardon add some more useful features to its Remote app.
The Verdict
Do you like to rock the party? If so, and you have the cash to burn, the Harman Kardon Onyx is the speaker for you. Its simple Bluetooth connectivity, stylish design and thumping bass and volume earn it high marks for the partying type. I just wish the Wi-Fi feature wasn't so frustrating, and it wasn't so expensive.
