Loudspeaker designer John Dunlavy: By the Numbers... Page 6

Atkinson: Any sort of active speaker—by "active," I mean a speaker that includes an amplifier and/or, as in the Meridian models, a digital processor—has had an uphill commercial struggle in the United States. This is, I believe, because it attempts to change the paradigm of what the owner's system should comprise. Do you see the days of having a separate amplifier, a separate D/A converter, and a separate loudspeaker, as being numbered?

Dunlavy: No. I think there will always be separate speaker/amplifier/cable components. I do think, for those leaning toward acquiring the most accurate system possible, full system integration like the Magnus is the future. It's the only way to achieve the ultimate goal of ultimate accuracy—which I hope we never achieve. I like to think that in the year 7000 people will be saying, "Well, I think this is a little bit more accurate than that." Otherwise it would take the fun out of it. That's the tweak end of the thing. But to me, there are all kinds of tweaks. There are people who tweak for the sake of tweaking, and they don't always achieve a better result by their tweaking. We try to tweak, and each time we make a meaningful tweak, that advances us closer to our ultimate goal of accuracy.

Atkinson: When will the Magnus be commercially available?

Dunlavy: That's a good question! [laughs] I hope we will have the first production units available by Christmas '96, or before. We certainly are putting every effort into doing so. Our problem is that we're totally dependent upon chip manufacturers, and the chips we need are unique.

Atkinson: The Magnus uses DSP to correct the loudspeaker's anechoic behavior. Have you thought about using digital correction of room acoustics?

Dunlavy: Yes. We're very familiar with what other companies have done and we don't want in any way to intrude upon their domain. I think that if you have a terrible room—basically a cube, say, with really reflective surfaces, so that you've got coherent reflections—digital room correction can just make a huge improvement. On the other hand, if you have a fairly good listening room, I think that the improvement is less audible.

In fact, I question, if you have a really good room, whether trying to digitally correct it is necessarily the way to go, long-term. And I'll tell you why: We become acclimated to the different temperatures or colors of a room, or whatever, over a relatively short period, sometimes no more than a few hours. Some people can correct very quickly when they enter a room, because our eyes tend, to a very large degree, to influence what we hear.

Atkinson: Let me describe an example to see if I understand what you're saying: You're sitting the other side of this large desk from me. Obviously the sound of your voice is going to have a very strong reflection from that desk. But because I am seeing the desk there and I can see you sitting there, I'm able to tune out the frequency-response changes due to that reflection? Your vision is a second channel of information that you use to modify what your ears perceive?

Dunlavy: Very much so. And you can certainly perceive that if you're in a fairly reverberant room and you're talking to someone: you're hardly aware of the reverberation, and you close your eyes, and within a minute or so you're thinking, "Golly, I'm having trouble hearing this other person."

Atkinson: I was recently talking to somebody who'd been working on room equalization up in Canada. He described the problem with digital room correction as a consumer product as this: If you put speakers in the wrong places in bad rooms, digital equalization makes a huge improvement. However, the people who put speakers into wrong places in bad rooms are not going to pay $5000 for a digital equalizer. The people who will spend $5000 are the ones who have good rooms and carefully position the loudspeakers in them. The improvement that can be introduced by digital EQ of the room is then very small.

Dunlavy: That's right. Digital equalization can make very audible improvements in some rooms. But the degree of the improvement that can be achieved with such devices becomes more and more limited the better the room is by itself.

We've worked very closely with one very excellent company in this country. I won't mention their name, but they are solely devoted to the design and manufacture of digital room-equalization equipment, and overall do a very good job. They brought their equipment to our own listening room here and allowed us to keep it for several days to play with. One of the things I found out—the one thing that we're very used to tuning out, whether we have eyesight or not—is the floor bounce, [the first reflection of the sound from the floor between the source and the listener]. It's always there, and we recognize it. I think when you try to include that within your digital-equalization time window—in other words, if you try to EQ out that floor bounce—it doesn't sound right.

Atkinson: John, you've had an amazingly variegated career. You've designed antennae for the military, you've worked in pure science, you were involved in the International Geophysical Year back in 1957, you've lectured at university, you hold patents for all kinds of things, even for cancer treatment and CD playback. You even moved to Australia for a while in the '80s. But despite all that, all you really seem to want to talk about is speakers. What is the fascination of audio?

Dunlavy: It's a labor of love. I like music and I like to hear reproduced music the way I hear the live performances. And it's a great challenge. Accurate audio reproduction is probably the most demanding challenge of any that I know of. So it's an interesting pursuit. And a very rewarding pursuit.

Atkinson: It's interesting that you say it's a great challenge, because surely it's a much more simple field than some of the others you've worked in.

Dunlavy: Yes and no. Speakers can be very daunting. About the time you think you've got an idea that, "Boy, this is really going to be the living end!" you put it together and measure it and say, "Ummm, why did I think that?" [laughs] We try a lot of new ideas out. Probably less than one out of 20 ever really goes beyond the first or second stage of development. Because it's fun to try new ideas and new things.

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