Ok, I think it is time to talk about imaging audio.

Everyone likes to discuss the performance of a loud speaker on multiple fronts but, do we ever really think about how an audience perceives the image itself? Not enough apparently. In the past few years I have been rethinking how we design performance audio systems for better imaging and clarity.

Let’s consider how we as humans hear things in real life. When we are walking down the street, we hear many things, especially on busy sidewalks. When you hear something stand out, your head turns laterally to that direction. Left or right, you will naturally turn in that direction. Looking up is considerably more effort, although the head will tilt up so the ears can be in a more natural position to hear the source of the sound. Your ears want to be on axis especially when it comes to high frequencies. You will always turn your head to hear something.

All in the Head?

So, why do we insist on putting audio over peoples' heads and still expect a good, full broadband image? Is it that we are all tied to what an architect might be giving us for space or is it that we have always done it this way? My real pet peeve is thinking an LCR system might actually work. Did we really think this was a good idea? Do you think a center source 35 feet above the audience’s heads will bring you a center image to the stage where you need it most? It is probably not a great idea and we do it all the time. Well, not me. I don’t buy into the promise of LCRs and haven’t for a very long time.

How about trying something for fun? Set up a good on-axis stereo source for a few students, play some good dynamic material and ask them to find the hole in the center. That would be a trick question.

Unexpected Discovery

Recently I have had the chance to put in a system that is left-right on a platform and almost completely on axis to the audience with a single sub in the center underneath the stage area. What hit me right away when I was commissioning this system was how natural it sounded and how all the voices seem to be coming from where they should be coming from: the platform. I also noticed that because this is a left-right system and the majority of the audience was now between the speakers, I could actually start panning the images. The result was magic. It was like mixing in a controlled studio environment. Then it hit me. The speakers are in the proper position for the brain to actually interpret what it sees: “Full frontal and on axis.” There were no speakers in the air for the brain to have to compensate for as well as acoustics to hear through. Not only was the image correct, the amount of acoustic 2^nd and 3^rd order reflections confusing the brain was down to almost an irrelevant level.

State of the art. What does it mean when we say that? I know we throw that term around a lot, even when some audio system designs are clearly anything but. The phrase itself connotes something very expensive and unreachable for many. Well, here is the truth. It may be far cheaper to look for someone on the cutting edge to design something in a purposeful way to solve your problems, rather than relying on traditional point source designs. You just cannot look at the price of a product and determine its real cost until you determine what it will save.

Here are two examples.

A very interesting thing happened to me on my way to everywhere.

After meeting with countless consultants and integrators all over the country, one particular repetitive statement began to reverberate in my head: “We don’t get much call for fiber, but we use it when we have to.” This was a shocking statement to me at first, especially considering it was coming from the technical leaders of the AV industry. But then I realized that this is just human nature clouding the progressive thought process. For all the greatness of mankind, one of the natural responses to change is “fear of the unknown” and this, I realized, is what drives that statement.