iPhone Screenshots


The HK Connect app works with Harman Kardon Onyx Studio 4. Use the HK Connect app for speaker configuration and software upgrade.

What’s New

Version 1.2

Fixed UI bugs.

Ratings and Reviews

1.5 out of 5
90 Ratings
90 Ratings
Rcbamm ,

Worked the first time. Second time..

Worked the first time connecting to TWO Onyx 4’s, yet when paired watching movies there was a latency problem. Voices in videos were half a second behind what was being displayed in videos. Second time after a few days the app won’t recognize the speakers even when BOTH are connected to Bluetooth.. Keeps telling me to turn my Bluetooth on and won’t go past that page. However, I still can link both Onyx 4 speakers without the app, which is nice. I noticed with one speaker connected to Apple TV 4 there was no latency. I have yet to further test both speakers. But speakers are great. I’m believing these issues will be addressed with updates. That’s why I’m leaving a review hoping Harmon Kardon will fix these issues.

harvey2268 ,

Great speakers but terrible app!

As others have said, the speakers sound amazing, and when the app works and puts them into “stereo” mode, it’s a beautiful thing. The problem is that it won’t stay in stereo mode for long and reverts back to “party” mode for no reason. Once it automatically dumps them back into party mode, it takes an act of Congress to get it back into stereo mode with the app stating that it cannot connect to the speakers, only shows one speaker, tells me to turn off my other HK app (there is no other app running), etc. At that point, I have to turn off the app, both speakers and start the process over of syncing it all again. Super frustrating!!!!!! HK app developers - please fix this app...pretty please!!

ZIs Finest ,

Welp...y’all were right.

I expected the very worse and got it quickly. Connected. Launched Stereo. Sounds great! Left Channel! Right Channel! Yea!!! I’m thinking...”What are they talking about?!?!”...and then BOOM...bye-bye Stereo. Hello pop-up messages.

Since that initial 5 minutes:
1. I’ve changed the sight-lines between my iPhone and the main speaker. (It’s Bluetooth and shouldn’t matter...
2. I also have kept the HK app open on my phone while playing music. (Plugged into my charging stand)
3. I turned off my notifications (have no idea if it matters)

But...not one interruption. Not one. I realize that’s not sustainable, but I know what I’m working with....and I’m very very happy.

Played an album from start to finish...clean.
And now the big test...March Madness. Connected to my smart TV now...Awesome!

Good luck.


Harman International Industries
62.1 MB
Requires iOS 8.0 or later. Compatible with iPhone, iPad, and iPod touch.
English, Dutch, French, German, Italian, Japanese, Korean, Portuguese, Russian, Simplified Chinese, Spanish
Age Rating
Rated 4+
© Harman International Industries, Incorporated.


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