Sonarworks says its True-Fi software can transform the music coming from your headphones, bringing it closer to what the recording artist heard in the studio, and improving any headphone’s performance by removing the coloration that gets between you and the music. That is an awesome promise, so the obvious question is, “does it work?”

Sonarworks sent True-Fi and some headphones for a test. The good news is that generally speaking, I found that Sonarworks largely delivered on its promise, improving to varying degrees the performance of each of the headphones I tested.

How does True-Fi work?

Sonarworks developed another software program, Reference 4, that is aimed at recording studios. The company says Reference 4 is used in more than 30,000 of these facilities worldwide. Reference 4 adjusts the frequency response of supported models of studio monitors (loudspeakers) and headphones to match the company’s studio reference sound standard.

True-Fi, by contrast, works only with headphones (287 models were supported at press time) and is designed for the average consumer. True-Fi works on both Windows and macOS, and there are Android and iOS versions in the works (these are available for “early access” in the app stores, but I did not evaluate either). Sonarworks announced at CES in January that customers who purchase a True-Fi license before those apps are released for sale will receive a free upgrade for a lifetime license to the mobile versions. A free 10-day trial of the desktop version is also available.

Sonarworks’ True-Fi functions in a similar vein to today’s top room-correction packages, such as Audyssey, Anthem ARC, Dirac, and Trinnov. If you’ve ever examined a frequency-response chart, you’ll note that it is not ruler flat. The typical curve is riddled with peaks and valleys, indicating that the drivers inside the headphone will overemphasize some frequencies and under-emphasize others, coloring the audio reproduction compared to what was recorded in the studio.

In an ongoing effort, Sonarworks measures and analyzes each supported headphones’ frequency response, looking for its shortcomings. Once this analysis is complete, the team applies the appropriate inverse curve to address those frequency peaks and dips. The goal here is to make each headphone’s final sound match their studio reference standard as closely as physically possible.

It’s tempting to think that headphones should exhibit ruler-flat frequency response, from the bottom of the frequency spectrum to the top, but I’ll point you to the pioneering work of Dr. Sean Olive and his colleagues at Harman International, which suggests otherwise.

Customized sound based on your age

True-Fi doesn’t just compensate for a headphone’s frequency response shortcomings, like an EQ package would. As we age, we lose our ability to hear high frequencies. True-Fi therefore also takes into account the listener’s perception of sound, adjusting its target curve based on your age and gender.