When you hear the words Harman Kardon (HK) you mostly think about car audio, or you never heard of them. But HK manufacturers a lot of high-end audio products, including portable Bluetooth speakers. And HK Onyx Studio 4 is their flagship coming to portable speakers. This is why we figured out it was an excellent product to test and review for you, to widen your perspective of speakers.

The speaker is the fourth edition in this line, as the name says it and with it comes a lot of improvements over the previous speaker. Onyx Studio 4 is an excellent speaker with great audio quality and from my point of view is a close competition to the Bose Soundlink Revolve+ (which is my all-time favorite Bluetooth speaker) and UE Megaboom, and Bose Soundlink III


  • Decent sound for its price
  • IP66 water-resistant
  • Priced correctly
  • Great price at the moment


  • Confusing controls
  • Battery life is bit lower than average

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Harman Kardon Onyx Studio 4 Wireless Bluetooth Speaker Black (LATEST...

For anyone who is familiar with those previously, three mentioned speakers will know that HK has to fill big shoes to compete with those speakers. And I like to think that HK is capable to fill those shoes in audio quality because previously tested HK speakers had great audio quality.

First of all, you might think that Onyx Studio 4 is not capable of directing sound equally because of its “flat” design, but the speakers itself are a bit curved that allows the speaker to address the sound at a wider angle which of course makes the sound project equally.

The low end is rich and powerful with excellent thump added to it. While the bass is powerful and deep, HK managed to get thru bass-heavy songs without any real distortion or drop in bass even at higher volume.

The Mids has accuracy and character to them making a lot of instruments sound fantastic, but highs have clarity and character which even more improves its sound. Overall the speaker is very well balanced, and it is capable of playing almost any track without any real distortion at high volume. We had some moments when it seemed to distort a bit, but we figured out that it may be because of the tracks audio quality as those were some newer test songs for us.

Battery and Mic

Onyx Studio 4 has improved battery compared to its previous version Onyx 3 which was capable only up to 5 hours of playback. But Onyx 4 has capable to 8 hours of playback, which is still very weak and low compared to other speakers at the similar price range. On tests, we managed to get 8 hours playing at medium to low volume, and when playing at max capacity, it dropped to 6/7 hours of playtime.

Onyx Studio 4 has an inbuilt microphone with noise, and echo cancellation which while tested worked flawlessly and people we spoke too did not realize that we were talking thru a portable speaker.

Design and features

Harman Kardon Onyx Studio 4 Wireless Bluetooth Speaker Black (LATEST...
  • Amplify your listening experience by wirelessly connecting more than 100 HK Connect+ enabled speakers
  • The rechargeable battery supports up to 8 hours of playtime
  • Stream music wirelessly via Bluetooth to enjoy room-filling sound Connect up to 2 smart devices at the same time and...

Design for Harman Kardon Onyx Studio 4 follows its previous speakers in design with the roundish shaped speaker. The plan is kept as simple as possible without crazy colors, flashing lights and simple colors. Such a simple design is very pleasing to the eye and can fit in almost any room design, and the speaker feels very sturdy and well built.

Well, HK has never been really about a lot of features because we believe that they like to make their audio quality speak for themselves and that they sell speakers focusing on sound quality, not features that are packed into it. They have features, but only the most necessary ones.


Onyx Studio 4 has Smart Bluetooth which allows connecting two devices at the same time so you can swap who the DJ is, but to sync more speaker, you will need HK Connect+ app which allows up to 100 speakers to be connected if they support HK Connect+ feature. Built-in mic let for speakerphone calls and has great quality plus added features like Siri/Google voice controls allows for the even more comfortable use of the speaker.

Another upgrade is that Onyx Studio 4 now has not only Bluetooth capabilities, but Aux port too which allows connecting your phone or other media player system to be connected, and we tested it with Chromecast audio, and it worked great with it also.


Harman Kardon Onyx Studio 4 is an impressive sounding speaker with good balance at the mid and high end, but the bass could do some more adjustments and improvements, overall it is an amazing sounding speaker. While its battery life is average at 8 hours, HK is more as an indoor portable speaker, and it won`t be an easy item to take on a trip due to its size.

At the moment of this review Onyx Studio 4 is at a great price and even at its full starting retail price it is an easy speaker to recommend for people who are searching for one that has an excellent audio quality and features/ battery is not so important to them.

Last update on 2020-08-20 at 15:37 / Affiliate links / Images from Amazon Product Advertising API


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