The Onyx Studio 4 is a black disc that measures 11 inches in diameter and is shaped like a convex lens approximately five inches thick at its widest point. It stands on two metal legs built into its body that let it sit at a slight angle. It features a black cloth grille bearing the Harman Kardon logo on the front and a rubber passive radiator with a metal disc (also with the Harman Kardon logo) on the back. Above the radiator, a large grip makes the 4.6-pound speaker easy to carry when moving it around. The speaker ships with a transparent plastic cover on the metal plate covering the bass radiator. It’s easy to miss, but must be removed for the speaker to work (and not produce a very strange-sounding low end).
The controls on the Onyx Studio are minimalist to a fault. Around the edge of the speaker sit Power, Volume Up/Down, and Bluetooth pairing buttons, and that’s it. The inputs are even more scant; besides a power port and a micro USB port, the Onyx Studio offers no physical connections. The power port is proprietary, and connects to a laptop charger-like power brick with a separate power cable for plugging into the wall. The micro USB port is just for firmware upgrades, so the speaker has no options for wired auido playback. This is surprising, since nearly every other Bluetooth speaker across all ranges of sizes, prices, and feature sets offers at least one auxiliary input.
The Onyx Studio is technically portable, but it’s not a speaker you can casually take anywhere. It’s bulkier and feels less rugged than other, smaller Bluetooth speakers like the Bose SoundLink III, and Harman Kardon rates its battery at a scant five hours compared to the Bose’s 14. The battery and handle make it easy to move between rooms and take out to your backyard, but it’s not a speaker you can just toss in your bag and take anywhere.Karman Kardon Onyx Studio
Performance – Onyx Studio 4
For a one-piece Bluetooth speaker, the Onyx Studio puts out some impressive sound. It sports two 3-inch woofers, two 3/4-inch tweeters, and two passive radiators, with 15 watts going to each active driver for a total power level of 60 watts. Harman Kardon claims the speaker boasts a frequency response of 60Hz to 20kHz, and the bass response seems to confirm that. The speaker reaches deep enough into the low end to offer an appreciable sense of rumble, and handled the sub-bass synth hits in The Knife’s “Silent Shout” at full volume with plenty of force and no distortion.
The Onyx Studio emphasizes the low end slightly, and some audiophiles might be disappointed with that focus. Lows and low-mids get plenty of presence and warmth, as I heard from the robust-sounding upright bass in Miles Davis’ “So What.” The piano and horns were still the highlight of the presentation, but the higher notes lacked some of the brightness other speakers offer with brass that allow it to cut through the mix. It’s still a very satisfying sound that doesn’t boost the bass too much, but it won’t appeal to purists who want the most accurate, flat response.
The Rolling Stones’ “Gimme Shelter” benefits from the focus on low end and the slight softening of treble. The opening plinky guitar notes, which often sound quite bright on most speakers, sat back slightly to share the stage with the bass in the intro. It wasn’t the most energetic reproduction of the song I’ve heard, but the strong bass and rounded lead gave it a pleasant sense of sculpted balance.
Monster Magnet’s “Negasonic Teenage Wasteland” also benefited from this effect. Dave Wyndorf’s vocals are usually just deep enough for the higher, sharper guitar riffs to overwhelm them with a flat-response speaker, but the boosted lows and pulled-back high end kept them anchored in the center of the track.
The Onyx Studio 4 was the worst scorer in our portability testing. It earned a 2 out of 10, far off from the top score of 10. At 4.5 pounds the Onyx Studio 4 is almost three times heavier than the next heaviest speaker in our review. It is also quite large (it is essentially a flying saucer with an 11-inch diameter) and either won’t fit in or will hog all the space in any backpack or bag. We’d be hard-pressed to think of a time we would bring this speaker further afield than the backyard patio. It might make it on a car camping trip, but with just 4.5 hours of battery life, it won’t make it through very many campfires.
The Studio 4 has a carrying handle which is convenient for moving it around the house but you probably won’t want to carry it much further than that.
The Onyx Studio 4 was one of the loudest speakers in our testing, sharing the top score of 9 out of 10 with the JBL Charge 3, putting it well ahead of the low score of 4. It is able to retain sound quality at high volumes and would be able to fill most of an average sized house with sound. This is definitely the speaker we’d choose if we wanted to throw a big party. However, that party would have to be at our house, because we wouldn’t want to have to lug the speaker around.
The Onyx Studio 4 lasted 10.5 hours in our battery life testing, well longer than the manufacturer’s claim of 8 hours, earning it an average score of 5 out of 10. Considering this is a speaker that one would most likely use in or around their home, that feels like more than enough battery life. It is also, conveniently, a good bit longer than the average backyard barbeque.
The Onyx Studio 4 earned a high score of 8 in our sound quality testing. With its large size it was able to produce, deep, resonant bass, which wasn’t quite as deep but was much clearer than the bass of the JBL Charge 3. It combines this bass with crisp treble and a large dynamic range to create a full sound with a good amount of depth. Occasionally the Onyx Studio 4 would lose some clarity when playing high pitched notes, something at which the Bose SoundLink Revolve was more adept.