In Your Headĭescribing the basics of room acoustics in just a few paragraphs is possible only by lightly scratching the surface and by almost completely ignoring the field of psychoacoustics. As with the response anomalies caused by early reflection interference, Sonarworks attempts to equalise the effects of low‑frequency standing waves at the listening position. Like fingerprints, no two rooms are ever the same. As illustrated on the room mode calculator at there are multiple potential standing‑wave modes in any given room. The side walls and end walls will, of course, also potentially create standing waves.
half the wavelength), I ought to expect one series of standing waves starting at 68.6Hz. Knowing that the first standing‑wave frequency can be calculated through dividing the speed of sound (343m/s) by twice the room height (ie. My room, for example, has a ceiling‑to‑floor dimension of 2.5m. Standing waves will occur at frequencies where the dimension between boundaries equals half the wavelength (and multiples of it), and it’s not rocket science to do a quick measurement of your studio room dimensions to identify some frequencies that might cause trouble.
That’s a result of standing waves between room boundaries. We’ve all no doubt experienced the phenomenon of moving the listening chair back away from the monitors and finding that the volume level of specific low frequencies changes. It is these peaks and dips that Sonarworks aim to equalise and flatten.Īlong with boundary reflections, real‑world rooms also play host to resonant standing waves, defined generally by the distance between room boundaries, and these will result in significant peaks and troughs in volume level at different locations in the room. Sometimes the interference will be constructive, and a response peak will result, and sometimes it will be destructive, which will result in a response dip. But reflected sound, thanks to the fact that it has travelled further and is delayed, will also interfere with the direct sound.
Reflected sound that arrives within a few milliseconds of the direct sound, known as early reflections, will be integrated by the brain, and although the direct sound will still dominate, the tonal character perceived for the audio event will be a composite of the direct sound and early reflections. The way our ears and brain deal with these multiple arrivals of sound energy depends firstly on how far apart in time they are, and secondly on their relative levels. And that reflected energy will be imprinted with both the off‑axis response of the monitors and the particular absorption characteristics of the room boundaries it has reflected from. In the real world, however, we hear not just the direct sound energy that leaves the monitors, but also energy reflected from the room boundaries. If we were all lucky enough to work in studio rooms of infinite size, or in rooms with boundaries that offered perfect absorption of acoustic energy, there’d be no need for applications like Sonarworks to compensate for room acoustics because we’d always hear just the flat, direct sound from the monitors. Sam’s conclusions on Sonarworks’ ability to improve headphone monitoring were entirely positive, but there’s no denying that the technical and psychoacoustic challenges inherent in correcting the response of monitors and listening rooms is a whole order of magnitude or two greater, so it will be fascinating to see how things pan out.īefore I get to describing how Reference 4 performs, however, I think it would perhaps be useful to examine what happens when a monitor plays audio in a room, and why there might be any need for ‘correction’. My colleague Sam Inglis reviewed the headphone calibration elements of the new Sonarworks 4 package back in the February 2018 issue of the magazine, but it is also designed to analyse and correct the quirks of monitor speakers and room acoustics, and a look at this aspect of its operation has long been on our list of things to do.
Sonarworks software has been widely lauded for its ability to correct the sound of headphones. Asymmetric listening setups can be accommodated. Screen 1: The first step is to input your room and speaker‑placement dimensions.