How Dirac Enhances the Sound Quality of OnePlus, Xiaomi, OPPO, and Huawei devices

How Dirac Enhances the Sound Quality of OnePlus, Xiaomi, OPPO, and Huawei devices

You might not have ever heard of Dirac, but if you’ve used a Xiaomi, OPPO, Huawei, or OnePlus phone in recent years, chances are you’ve heard their software in action. The Swedish audio firm works with an increasing number of device makers to optimize the sound quality of smartphone loudspeakers and headphone outputs.

Dirac’s smartphone suite, Power Sound, boosts the bass and enhances the clarity of speakers by correcting impulse, phase, and magnitude frequency response. Unlike off-the-shelf equalizer solutions, Power Sound is built into device firmware and it applies tweaks at the system level.


I had a chance to experience it firsthand at last year’s Mobile World Congress, and the difference was striking. The loudspeakers on a Google Nexus 6P with Panorama Sound enabled (one of Power Sound’s filter effects) produced crisp, clear headphone-quality audio with an ultra-wide soundstage. During a music video, strings on an acoustic guitar sounded as though they were being plucked inches away from my ears, not coming from a smartphone speaker several feet in front of me.

To learn more about the technology, I had an opportunity to speak over the phone with Erik Rudolphi, Dirac’s General Manager of Mobile. We spoke about the company’s current partnerships, the applicability of its solutions to streaming music apps, and future plans.

Erik Rudolphi, General Manager of Mobile at Dirac.

Kyle Wiggers: First, let’s talk about the current incarnation of your smartphone solutions, Dirac Power Sound and Dirac HD Sound, and how devices benefit from them.

Erik Rudolphi: So, we have basic technology that we use to track the impulse response and the frequency response of headphones or speakers. What we add to that for smartphone speakers is to make them play as loud as possible and enhance the bass—that’s not needed for headphones normally, but it’s necessary for speakers. So, there’s a set of […] different technologies to enhance the base, and there’s something we do called called Virtual Bass which is basically tricking your ears. What we do is we play the overtones of the bass, and if you play the overtones at the right level, your ear fills in with the fundamental tone and believes that there is base.

We made a lot of noise about our Xiaomi partnership at CES [Consumer Electronics Show], and also, at MWC [Mobile World Congress], we announced a partnership with AAC Technology. AAC Technologies happens to be the world’s largest manufacturer of the micro speakers that go into the phones that we’re supplying to—at least all the big OEMs that I know of. So, that has been a strategic partnership, and we develop software that controls the speakers and they develop speakers that are designed to be controlled by our products. That’s something we’ve been working on for two years and we’re starting to see the fruits of that.

K: For me as a smartphone buyer, I know the audio on one of the smartphones enhanced by Dirac’s technology is probably going to sound superior compared to the average phone. With the AAC partnership, how can the average person expect to benefit? Maybe you can explain.

E: So for instance, we have been showing up to MWC with a few mockups for stereo speakers solutions and smartphones. One of the challenges with stereo speakers is real estate. Last year at MWC, we demoed our technologies on [Huawei Nexus 6P]. The benefit of the Nexus phone is that it has two large speakers, so it’s relatively easy to do an impressive demo. Now, most of our customers want to also have a large display. There comes a fight between the audio and the display, so there’s no room for speakers. So actually, in one of the demos we have just a very tiny speaker on top of the phone for the receiver. That is the earpiece, but that receiver can also produce pretty high output, so it can be pretty loud.

Then you have the speaker, the down-firing speaker the bottom, and the trick we do here is that we can balance them, even though the sound is very different from the two—the speaker on the top and the speaker on the bottom. We can balance the two and we can make great surround sound from those two speakers.

And then there’s a smart speaker mock up we’ve created that is producing sound with micro speakers. We can produce pretty loud Hi-Fi sound from a very small compact package, like an Echo Dot, but it’ll sound much louder and much better than the original Amazon Echo Dot.

K: Quick question about the smart speaker implementation. Would that be from all directions? I mean, it wouldn’t matter where you’re standing in the room—it would sound loud and clear, right?

E: Yes.

So, we also have a new demo that is an AR [Augmented Reality] headset mock up. What we do there is we have two speakers, because in AR you don’t want to cover your ears and you want to hear the natural sound from the surroundings, but on top of that you want to add the AR sound. What we do is when we have two speakers on top of ears, not in front of you but on top, and we beam the sound to your ears. So that means it can play pretty loud but you won’t be able to hear much of your neighbors.

K: That’s really innovative. Nobody’s really tackled that problem.

E: Right. So this is something where were we—I mean, AR is really not on the market in terms of development platforms, but it is coming. And also, we are demoing a new version of VR [Virtual Reality] where we have a true [virtual] surround sound system  […] that’s like a sphere of speakers around your ears. You can hear sounds coming from anywhere.

K: Like true directional audio.

E: Right.

K: Oh great, awesome. So, you mentioned how consumers want phones with larger edge-to-edge displays that don’t really have room for stereo speakers. And you mentioned your solution is, basically, you can shrink it down right and maybe stick [the speakers] elsewhere. But Google recently bought [UK audio startup] Redux, and that’s a completely different approach—using the screen to produce audio. So I was wondering, what do you think about that approach and how does yours differ, and what are the advantages and disadvantages there?

E: Yes, audio displays have been a hot topic in the industry for five to seven years or so. We still haven’t seen anything convincing on the market. We are working on solutions for that, also, but I think it’s a bit too early to say. I know there will be launches—I’m not sure whether they’ll be with Dirac. But this is an application where you’ll need algorithms to control the display. So it’s a clear opportunity for us and we are working on solutions together with partners.

I think that’s as much as I can say. But I think the problem can be that if you want good stereo sound to really control the display, to control the direction of the sound, that will be a challenge.

K: Right. So it kind, for lack of a better term, [the sound] sort of radiates outward from the screen. Is that what you’re saying? It’s not like you’d get the stereo experience with two discrete channels?

E: I think that’s a big challenge and I haven’t seen any solution yet.

K: Gotcha. So staying on the smartphone topic for a second, you’ve integrated your technology into a few Xiaomi devices. I’m sure a lot of smartphone users would probably pay good money to have their speakers enhanced in that way. Do you think it will ever be possible to sell this solution as an app, or is there a specific reason you’ve gone the OEM route? Does it require hardware optimization in addition to software?

E: To have a hardware agnostic solution as an app?

K: Yeah.

E: Of course you can have any EQ, but what you could do is an intelligent system that would listen to the output and then do some kind of self-correction. It would take some time—that’s as much as I can say.

The problem would be that the microphones you have in your phone are too close to the speaker to make a true representation of the sound that you experienced. It’s conceivable, but it’s not going to happen soon. It’s pretty complicated to do that kind of thing.

Another option is, if you think of headphones and the digital headphones you use with USB Type-C and Bluetooth, you could identify the headphones, and if you know these headphones have a beat pattern and you have a library of profiles, you could automatically download the profile for the headphones. So that’s of course an option. The problem with it, though, is that you can’t enhance system-level audio streams—it requires a deeper integration into the phone. There has to be some kind of pre-integration. You can make an MP3 player or something, for example, but nobody plays MP3 files anymore. We want our technologies to work on the system level and support YouTube and Spotify and all of these different audio streams.

K: That makes sense. Otherwise, popular applications that people would want to use wouldn’t really work. It would be kind of jarring experience, too, if some apps were enhanced and others weren’t. I can understand how that would be subpar.

E: Yes. So, it of course would be possible to offer YouTube subscribers or Spotify subscribers a premium solution. It’s something we’ve been thinking about but haven’t actively pursued, but it would be possible.

K: So it would be bundled, then? Just to be clear, you would pay a little bit more per month as a subscriber for example, and then benefit from this enhanced audio? Would it be built into the app?

E: Yes, that’s right. Any audio that is streamed through the content provider can benefit from this kind of enhancement.

K: I would be really interested to see where that goes, because we’ve seen some audio streaming services try to differentiate themselves with higher-quality streams, like Tidal for example, and that hasn’t really taken off in the way that maybe some of them expected. That would really set some of them apart.

So, to get back to your initial question. I was going to ask about focus. Do you want to introduce your technology to manufacturers [other than OnePlus] that sell phones in the U.S.? Is that a specific goal for you?

E: Of course we would like to, it’d be very helpful for our brand and brand recognition in the Western world. The U.S. market is dominated by Apple and Samsung, so of course we’re talking to them, but it’s not been an easy sell. They have their own technologies.

But a company that we’re glad to work with is OnePlus. Also, Xiaomi has started selling [its phones] in Spain and Poland, I believe—not just Asia. And of course they are extremely successful in India now. Xiaomi has over 25 percent of the market in India, I think, and they basically […] killed the domestic brands there. So that’s also an interesting development. Huawei of course is taking over market share. So I think [those companies] will probably change the [smartphone] market in the coming years.

Thanks for sticking to the end of this interview! We would love to hear your thoughts on Dirac and/or smartphone audio quality in general. Let us know your opinion in the comments below!

About author

Kyle Wiggers
Kyle Wiggers

Kyle Wiggers is a writer, Web designer, and podcaster with an acute interest in all things tech. When not reviewing gadgets or apps, he enjoys reading the New Yorker, tinkering with computers, and playing the occasional game of Rock Me Archimedes.

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