Loudspeakers and headphones are by nature imperfect mechanical systems. Regardless of price or quality, there will always be a degree to which the physical properties of the device impact performance. Dirac HD Sound® challenges these physical constraints, bringing to life the hardware’s full potential.



“How good is it? I listened for about ten hours…compared the Apple EarPods with the Dirac app directly to the $1,100 Ultrasone Edition 8 on an iPhone 5. The optimized Apple EarPods are better”

 – Ken Rockwell, famous audio reviewer



True performance enhancement


Dirac HD Sound® enhances an audio system’s ability to faithfully reproduce sound by examining and adjusting for the problems inherent to mechanical devices. For example, by correcting an audio system’s impulse and frequency responses, the technology can transform what began as a distorted sound stage, feeble bass or poor clarity into a pristine, dynamic sound experience.


Impulse and frequency response


An audio system’s impulse response affects the clarity, tightness and all spatial aspects of sound, such as location and detail. By correcting impulse response, listeners can enjoy a more dynamic sound stage, more powerful bass and improved clarity of sound.





Frequency response reflects how balanced the entire range of sound is. An ideal frequency response curve should be flat, meaning the entire range of frequencies, from lowest to highest, accurately represent the input signal. Typical indicators of poor frequency response are harsh treble or thin bass.






“The difference between the Dirac HD Player engaged and not engaged is nothing short of amazing”

 – Tom Andry, Associate Editor, Audioholics


There is no perfect audio system


No matter how well designed, all earphones suffer from one fundamental problem: they’re mechanical devices, and all mechanical systems produce acoustic imperfections.

 Unlike sound effects and EQ solutions, which only mask these imperfections, Dirac HD Sound utilizes both impulse and frequency response correction to empower speakers and earphones to performer at their highest potential.


Custom-tailored optimization for each audio system


This is no one-size-fits-all solution to sound optimization. At Dirac, we analyze the acoustic behavior of each individual audio system, including how earphones interact with the human ear, and optimize 

each system’s performance based on careful measurements and modelling. With this holistic approach, Dirac HD Sound® optimizes the complete audio system – from smartphones to earphones and even the human ear. 

FAQ about Dirac HD Sound

1. My phone is powered by Dirac HD Sound. There are optimization solutions for several headphone models, can I have Dirac HD Sound on no matter which headphones I use?

Please always select the optimization solution that is tailored for your headphones.  We do not recommend you to have Dirac HD Sound on if there is no optimization solution for your headphone model in your device.

2. Can I use EQ when Dirac HD Sound is on? Can EQ replace Dirac HD Sound?

You may use EQ and Dirac HD Sound at the same time. Dirac HD Sound is a measurement-based earphone optimization technology, which is fundamentally different from EQ or sound effects. Dirac HD Sound enhances the performance of your earphones, while EQ can help you dial in the sound that suits you best. They serve different purposes and are not used interchangeably.

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