I Love Analogies
There is a problem out there that is all too common. It is a mindset that room acoustics can be ignored. “The sound will be wonderful because we will spend the money for good technology” is what I hear. I’ve had clients not want to talk about the room at all. They just wanted to know what sound system to buy to make it sound great in their hard round room and “invisible, wireless, and inexpensive too please”.
It seems this stems from an almost unconscious belief that there are good sounding speakers and bad sounding speakers and if they were to just put the good ones in, the sound that reaches their ears will be good. To be fair, this type of intuition serves one fairly well in a home setting where the room dimensions are small and a wealth of acoustic absorption from carpet and plush furniture negates many of the acoustical issues that exist mainly in larger rooms. It seems the effect of the room never enters most people’s thought process for larger rooms as a result.
I've been reading Synergetic Audio Concepts founders Don and Carolyn Davis’ book if bad sound were fatal, it would be the leading cause of death and Don makes his love of firearms well known. Possibly because of this, I offer the following analogy.
- Designing a room with a sound system is like designing an indoor shooting range. A good outcome is dependent on the room. At a shooting range, if a bullet isn’t trapped it could ricochet around the room and kill someone regardless of how expensive the gun used is.
- Using a gun with accurate sights, skillful aiming, and a straight barrel are all needed for you to hit the bull’s-eye. However, after the bullet goes through the target it is going to keep going. If it bounces around the room and hits you’ve had a pretty bad day at the range.
- Similarly, while having a good quality sound system is requirement for good direct sound, after the direct sound reaches you it keeps going and bounces off the walls, ceiling and floor and can kill that great sound we had going. The direct sound from the speaker(s) and the reflected sound from the room are added together in our heads and it is based on this sum that the quality of the audio will be judged.
This is an imprecise analogy of course. Thankfully bad sound isn’t fatal. A loudspeaker is also not really like a rifle at all firing a single bullet where you point it. It is closer to a shotgun or a blunderbuss spraying into an area.
For example, no loudspeaker you’re going to put up on a stick is simply 40 degrees x 90 degrees regardless of what the spec sheet may state. The pattern changes with frequency. The pattern will look nothing like a 40 degrees x90 degrees cone at the lower frequencies especially. The pattern is also affected by what speakers or surfaces are very near it. Audio can be messier than firearms rest assured. There are many more variables to optimize while it seems some building committees would rather just shoot from the hip.
Let me also be clear. Choosing the right loudspeaker, dispersion pattern, placement and aiming are all important steps to minimize unwanted interaction between the sound reinforcement system and the room. Still, the best loudspeaker in the world listened to in a terrible room still ends with a terrible result.
Garret Maki
Garret@K2Audio.com
http://K2Audio.com/
