Reference vs. Preference
Here is a trick question: “What if I correct the acoustical problems in my room, but I don’t like the resulting sound?” If you find yourself asking this question you have stumbled on the line between Reference and Preference.
Let’s look at what room correction aims to do. You start with a good (or not so good) set of speakers, you place them in a room and what you have is problems: acoustical problems. Sound from the speakers comes to you from many different directions. Some of it directly, but most of it after interacting with the floor, ceiling, walls, and furniture. Because each of these elements is at different distances from where you sit, the combined sounds arrive at slightly different times and what you hear is a form of distortion. Voices can sound unnatural, the low frequencies are muddy or boomy, and the high frequencies lack air and sparkle (yes, these are all technical terms).
A well-designed room correction system captures information throughout the listening area and analyzes it in the time domain. It then creates an equalization solution for each speaker and applies it so that the response matches a certain target sound. And here is where we first catch a glimpse of the Reference vs Preference line: What should this target sound be?
The answer lies earlier in the chain, where the content is made. The film industry adheres to a set of strict standards that are used in the creation of the content and in the reproduction of the content in movie theaters. These standards define the location, level, and frequency response (target sound) of the speakers in the audio system. They are in place so that content created in one location can translate perfectly to thousands of movie theaters. The same translation should apply when the content is played back in a home theater.
So, calibrating your home theater system “to reference” means that: (i) the levels of each speaker and subwoofer are matched to each other; (ii) the playback level of the system reaches a certain sound pressure level when the volume control on your AVR is set to “0”; (iii) the time delays for each speaker and subwoofer are adjusted so that sound from all of them arrives at the same time to the central point of the listening area; and (iv) the frequency response of each speaker and subwoofer is such that the perceived octave-to-octave balance is the same at home as it is in the dubbing stage or the movie theater.
Reference is a good thing because it gives us a way to reproduce the art the way it was made. But, you might say: “I like more (or less) bass.” OK, I’ve never heard anyone ask for “less bass,” but I suppose it’s possible. As soon as the word “like” is uttered we have crossed into the uncharted waters of the Preference abyss. It can be a fun place to be and there is nothing wrong with applying personal touches to your sound, especially if you are the one enjoying it. But know this: It’s not the job of a room correction system to determine your preference. That is entirely up to you. What room correction gives you when it delivers reference is a known baseline and the ability to apply preference consistently. Without it, boosting the bass for some content would not sound the way you want it for other content because you are not starting from a known condition. If you want to apply your preference, I have some words of advice: “Start with reference.”
