Paul Hales: A Passion for Speakers Page 7

Deutsch: How much do you rely on measurements?

Hales: I rely on measurements a lot. I probably use subjective and objective evaluation almost equally; in both the lab and the listening room, I know what I'm shooting for. And now I'm even starting to understand what the sound I'm shooting for looks like in the lab. So I can get even closer to the sound in the lab than I used to get.

Deutsch: You were telling me that there's an expensive tweeter you're very fond of, but it doesn't measure as well as some of the less expensive tweeters.

Hales: Absolutely. Some really cheap soft-dome tweeters—$7 or $8 soft-dome tweeters—have a more linear amplitude response.

Deutsch: So how do you justify putting this expensive tweeter into your top-of-the-line system when you know that it doesn't measure as well as the tweeter in your lower-priced line?

Hales: Well, in a general sense, there are still things we can hear that we can't measure. I can certainly correlate measurements with what we hear a lot better than I could even just a couple of years ago, but there are things that our ears detect that happen 30, 40, 50, 60 or more dB into the noise floor that we simply don't have the signal/noise ratio in our equipment to capture. As I mentioned, a tweeter that we considered for the Revelation Three that performed exceptionally well in the lab had a flaw that I could hear but the MLSSA system couldn't detect. I didn't do elaborate distortion measurements on the driver; perhaps that would have revealed it. I think harmonic distortion and spectral decay actually can give you a lot of information on the driver. For example, those magnesium-cone drivers that we're going to use in the larger models of the new Transcendence Series have the most accurate reproduction of instrumental timbre that I've come across, and they also have absolutely the cleanest waterfall I've ever seen. So they correlate. They all have very low distortion. The lowest-distortion speakers I've heard always tend to sound very at ease and very relaxed. And if second-order distortion comes up, they tend to sound more forced or...

Deutsch: ...congested?

Hales: Yeah, congested, and just not relaxed. They sound tense. So I'm starting to develop a correlation between the measurements and the sound quality.

Deutsch: Where else do you see the Hales Design Group going in the next five or ten years?

Hales: There have been some thoughts about taking the Revelation philosophy one step further, and designing speakers that are even more affordable and maintain a certain price/performance ratio. We want to make the best speakers possible at the price. And within that context, I don't have any preconceived notion that it means only two channels, high-end or hi-fi. Some day, that may include a nearfield studio monitor. I would love to have a whole bunch of extra time to pursue professional theater loudspeaker applications...I'm a lover of movies, and I'm particularly impressed by how soundtracks can affect your experience. We commented on this yesterday—about how bad a lot of the theaters sound. The big ones sound very good, but there are few of them. I would like to make products that enhance the aural experience that you get when you go to a movie.

Deutsch: And possibly recording studios?

Hales: Yes. I've visited a couple of recording studios, and, generally speaking, I think some high-end sensibility could benefit that end of the industry as well. The monitors they use have some pretty serious flaws, I think; they're not particularly refined. But the thing that struck me the most was how loud they play. Engineers listen much louder than we do in hi-fi. Seems to me somebody could take some of our high-end sensibility, apply it to other loudspeaker applications, and yield a product that's also better suited for the application, even though it's very different from our application. And vice versa. Dynamics and low compression, things that people go for in the pro market, could also help us out in home theater. In general, our speakers are terrible at the dynamics. And even the most dynamic speakers are horribly compressed.

Deutsch: "Our" speakers?

Hales: The industry's. Home hi-fi speakers. Because we have to go for bandwidth, and we almost necessarily have to sacrifice dynamics. Most of us probably don't even directly address the issue. I certainly address dynamics more now than I have, and I intend to address it even further, because I'm designing more and more of the drivers that we use. For example, there's probably a driver outside waiting for me in the receiving area right now. It's an aluminum-cone woofer intended for the Transcendence Series, and it has some pretty esoteric design elements directed at the dynamic problem.

Increased sensitivity is a huge step in the right direction. Anybody who's heard Klipschorns knows that they're immensely dynamic. That's because you're dissipating way less power in order to achieve the sound level you want. So if you're dissipating less power, less of the power is turning into heat, which is your enemy. Heat is where the thermal compression comes from.

All I gotta do to get my reality check is take my daughter to Disneyland, find the jazz band in New Orleans Square, stand 12' away from them, and listen to the trombone and the saxophone and the trumpet. You get a perspective on things—the sound power energy coming out of those instruments, unamplified, is so huge and so dynamic and powerful. A guy blowing into a trumpet makes our home hi-fis sound pretty silly.

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