AES International President Dr. Sean Olive, also the Director Acoustic Research for Harman International, tells PS that one of his biggest pet peeves is a lack of perceptually meaningful loudspeaker and headphone specifications for consumers. Here he is explaining what he means and what should change…
With loudspeakers, it is really common to state that the speaker bandwidth is 20 Hz-20 kHz. That by itself is meaningless because there is no tolerance given. It could be 60dB down at 20 Hz, which means you’re not hearing it at all. What all the research we’ve done has shown is that you have to measure the speaker all around and that a single curve cannot convey how good it sounds because people don’t always sit on axis; they’re hearing different direct sound and, of course, most of the sound comes from off-axis as reflections.
So the single spec doesn’t convey how good it sounds; you need to have information showing the direct sound, the earlier reflection, and the sound power. One graph can predict how good the speaker sounds with about 86–90 per cent accuracy, so the science exists, but for some reason our industry just doesn’t want to be upfront with the consumer.
Perhaps the manufacturers can’t measure it. Some also might think users can’t understand what they’d be seeing with such graphs, which I think is nonsense. It could be that the emperor has no clothes. If you have completely honest and meaningful specs, the people that are making the good products are going to do better and the ones that aren’t are going to go out of business.
Marketing has to educate the consumer to explain what these graphs mean. I am hoping that it is a matter of time. If it became a standard in the AES or some other organization, I think that would accelerate the process.
With headphones, it’s probably even worse because they don’t give tolerances at all. They just say it goes from 10 Hz-40 kHz. When people go in the store, the products cost from $50-$1,000 and they all have the same specs. So why should I spend more money? There is no clear indication which one sounds better. With headphones, there is an excuse that the science hasn’t existed to really come up with the right spec, but I think we’re getting close to that point.
These specs would force manufacturers to make better products, benefitting the consumers and the companies making the quality products.
In early November, Dr. Sean Olive became the president of the Audio Engineering Society International. As the Director of Acoustic Research at Harman International, Dr. Olive has conducted extensive research on the perception and measurement of loudspeaker and headphone sound quality. He has written about this and other topics on his Audio
Musings blog at www.seanolive.blogspot.com.