Sonarworks noted this problem and created the Reference 3 software in response. It should be noted that Reference 3 is also capable of creating speaker calibration profiles but this review will focus on the newly updated headphone calibration aspect of the software. The core of Reference 3 is an averaged frequency response profile, created using their proprietary Headphone Acoustic Power measurement system. A number of different pairs of the same model of headphone are tested, generating an average profile for each. Sonarworks analysed and created profiles for pretty much every discerning model of headphone you care to think of, and there are a couple of more niche options available, too. If you don't own a pair of headphones that's compatible with the pre-defined profiles, it's possible to buy a calibrated pair direct from Sonarworks or have your own pair sent to their HQ in Latvia for calibration. Either option results in a custom, one-off profile which is said to improve accuracy by around 5%.
Until now, the power of Reference 3 was only available when working in a DAW environment. Systemwide opens this up to cover all outgoing audio from your computer. This gives you across-the-board, flat sound from browser-based audio platforms like Soundcloud and Youtube through to standalone applications such as Spotify, iTunes or your chosen DAW. Sonarworks made what could be a confusing and complicated process exceptionally easy to navigate. After downloading and installing the software with the necessary licences, you're presented with a quick run-through of the calibration process. Three reference curve options are initially available to you: Flat, Custom and Predefined, of which Custom and Predefined offer a number of customisable presets. From there, you're asked to chose a calibration profile matching your headphones (the version I downloaded for this review came with a total of 87 different profiles). Like many others, I use the Sennheiser HD-25 II's for both DJing and production, and as an averaged profile already exists within the software, that's what I went with here.
As far as setup goes, that's pretty much it. You'll now be able to hear the corrected profile, which you can A/B by hitting the big on/off button in the bottom right corner. This corner of the software window also contains switches for mono monitoring and clipping prevention. I tended to find that the volume reduction caused by the profile was a little excessive. But by turning off the clipping prevention and sliding the software's output up to -1dB, I was able to get a decent level without noticeable clipping or distortion.
In the centre of the interface is the frequency graph, which gives you a visual representation of what Reference 3 is doing. Initially, you're presented with two curves: Before and Target. The Before curve is surrounded by a thicker, lighter line that represents the accuracy margin. With the averaged profiles, this is around +/-3dB while custom calibrated headphones manage +/-1dB depending on the model. It's possible to toggle on or off a number of additional curves, namely Correction, After, Phase Response and Limits. For me, I found the best way to visualise what Systemwide is doing without things getting too cluttered is to show the Before, Correction and After curves. What you'll generally see is that the Correction curve is pretty much a mirror inversion of the Before curve, with some disparity at the very low-end. This results in a final curve profile that is pretty much flat down to 100Hz, at which point the curve dips down to around -6dB with my set-up.
So, what does it sound like? Flat sound is generally not as pleasant to listen to as biased sound, and this is something that can take a little time to get your head round. However, with a little time and a lot of A/Bing, the benefits of system-level audio correction become clear. When streaming video on Youtube, it has the effect of simultaneously reducing a reverb-like boomy-ness from the sound while increasing the perceived stereo width. This makes speech sharper and clearer. In fact, it has a general propensity to increase stereo width across all sound sources. This is fine for higher register sounds but can occasionally have a slightly disconcerting effect with bass frequencies. Low-end sounds generally exist in the centre of the stereo field—an idea bought about in part due to the real-world difficulty of cutting low frequency stereo content to vinyl. It's also worth remembering that Systemwide only works on audio at a computational level. So once that audio passes through your soundcard of choice there is the possibility of sound colouration creeping back in.
Those issues aside, having flat sound as a constant makes a real difference in the long run. Not having to flick between flat and biased sound means your ears become accustomed to this new way of listening, allowing for more consistent and informed decisions regarding your music and how it stacks up against others. Reference 3 might not be the most exciting bit of software out there but it could end up being one of the most useful.
Ease of use: 4.7