I often get asked if digital room correction or room EQ is necessary for a given studio or listening room. My answer is that a professional tool, like Sonarworks Reference 4, will almost certainly improve your listening experience. The next questions that come up involve speaker choice, room treatment, and the fundamental fact that “you can’t fix acoustic problems with electronics.” Let me address these issues the way I would discuss this with a client. Don’t worry, this explanation involves no math and will explain why room equalization is effective at improving your listening environment.
First, allow me to present an analogy that everyone can relate to. We can assume that every new automobile can drive safely, comfortably and efficiently on a reasonable road in decent weather conditions. When we drive on bumpy or slippery roads the comfort and even the safety of our ride will be compromised. A simple improvement would be to upgrade our tires or shock absorbers. While stock windshield wipers are useable, for severe rain or sleet better windshield wipers will provide a much safer ride than basic or worn-out wipers. Compared to the entire car, the windshield wipers represent perhaps one-thousandth of the cost of the car but provide a measurable difference in the experience we have driving the car.
When we are purchasing a studio monitor system, we shop like we do for a car. We want something that is well made at our desired price-point. We want styling that suits our personal taste and we want confidence in the ability of speakers to produce accurate, enjoyable audio. Like modern autos, most modern modestly-priced speakers perform extremely well, with low distortion and excellent frequency response. Also like cars, speakers interact with the environment in which they are used, and small improvements, like upgrading your auto’s windshield wipers, will yield a noticeable improvement in your experience.
Professional monitors are designed and measured to perform exceptionally well in a perfect environment, like a free field or anechoic room. A set of monitors placed in your office, garage, or spare bedroom will no longer sound like the ideal speakers you purchased. The monitors produce the sound they claim to produce, but the room affects what we actually hear. You have created a new system that includes the speakers, the room’s acoustics and the electronics of your entire monitor chain.
Physical Room Correction
Every room and physical setup presents a unique sonic environment and we need to deal with certain acoustic problems to get even a reasonable sound out of our monitor system. For instance, the interaction of the speaker with the front wall of your studio will always create a dip in frequency response at some relatively low frequency. This particular problem will always exist to some extent in every room and with every set of monitors. It can only be improved by moving the speakers relative to the front wall and by proper application of bass trapping. No amount of EQ will fix this “bass suckout” problem because no matter how much energy you add at the problem frequency, the room dimensions will still provide the same amount of cancellation.
Other acoustic issues, like first reflections, proper listening position, and speaker-listener geometry also need to be taken care of in the physical realm. Move your chair, angle the speakers properly, and place absorbers and diffusers in the necessary positions. Too little bass trapping can also allow low frequencies to ring, or last longer than they should, which will smear the clarity of the low-end of your mixes. Proper setup and acoustic treatment minimizes the effect that the room has on the sound of our monitors.
Once the speakers and room are set up properly and optimized as much as is practical, there may still be some problems that we haven’t fixed. The remaining acoustic problems relate to our limited amount of space, money or simply the original construction of our building. These problems will be a fact of life no matter what speakers or corrections we can realistically apply, so we’ve done the best we can—returning to our analogy we have the best car we can afford.
Digital Room Correction
Digital room correction now comes into play to add the finishing touches that really polish the sound of the system. Like upgraded windshield wipers and better tires, several small changes in the performance of your system add up to a much-improved listening experience. Below are some of the improvements that you can expect from room correction software.
Sonarworks Reference 4 measures the frequency response of your system at thousands of frequencies—not like your grandfather’s ⅓ octave analyzer—and can create thousands of tiny adjustments that correct the frequency response variations of speaker drivers, crossover designs, and even small variations in room shape and treatments.
Every electronic component in your audio gear has a specific operating tolerance and if we have ten components, each with a 5% tolerance, the variation from the ideal can be quite noticeable. Sonarworks Reference 4 will measure and adjust for the real-world performance of your entire monitor chain.
Reference 4 will improve the stereo image by correcting the timing and volume differences between your listening position and the left and right speakers down to the hundredth of a millisecond and a tenth of a dB for each channel. Beyond the accuracy of a tape measure and a volume knob, this alignment will really solidify your center image and highlight the stereo placement of panned sounds.
As we mentioned earlier, the position of your speakers relative to the front wall will create a dip in certain low frequencies of our bass. Interestingly, while room EQ can’t solve this bass suckout, Sonarwork’s minimum or linear phase EQ can effectively tame peaks in the room response. Lowering these peaks, especially in the low frequencies, can really help flatten out the bass response.
Keep in mind, also, that our studio spaces are constantly changing environments. We might get a new sofa or new window treatments. We might add an extra chair or a new equipment rack. You might finally set up that modular analog synth that is the size of a grade-school whiteboard. Besides these obvious physical changes, you may change your monitor controller, interface or even the audio cables to your monitors. All these tiny changes add up to real differences in what we hear.
Wear and tear on your monitors can be expected, especially if you play your music loud at times. Speakers break in and break down and even electronic components in amplifiers and crossovers will age and start coloring your sound. Our brain gets used to changes that happen gradually and we may not notice small changes in our system’s performance. Be aware that while fresh measurements may look very close to the old measurements several one percent changes add up to noticeable difference!
Ultimately, I recommend that you measure your room every three or four months and measure again whenever you make changes to your room’s layout or furnishings.
Keep It In Perspective
Ultimately the most important thing about our room is what the audio sounds like. Room correction, like Sonarworks Reference 4, provides more than enough polish and improvement to a monitor system to easily justify the time and cost. Clean your windows to the sonic world and help your monitors sound their best!