How to Design Great Speakers: A Henry Kloss Story

In about 1997, when I was at Cambridge SoundWorks, I wanted to write an article about how to design great sounding speakers. To this day I think it's amazing how many not-great-sounding speakers are designed and made. You'd think by now, with all the computerized measurement tools on the market, that the design process would be, well, a math equation. And if that were the case, why were so many speaker manufacturers flunking? Because the world is full of unexceptional speakers in just about every price range.

In the 1970s, back in the Advent days, I'd heard Henry Kloss tell stories about well-intentioned people designing speakers with the goal of a perfectly flat frequency response curve. It turns out that speakers that look perfect on paper often sound lifeless and flat. And while measurements certainly had their place, they were only part of the process.

Back then, and later at Cambridge SoundWorks, Henry did a lot of his design work by listening -- not to music, but to noise. He would use a generator to create pink noise and listen to it while trying different crossover combinations. He built this cool panel that was loaded up with chokes and capacitors that he could connect in different combinations using switches and speaker wire connectors on the front (see photo). He would spend hours and hours, for days and weeks, perfecting the tonal balance of a speaker. This process, called "voicing" a speaker, is crucial. And it's a combination of art and science. But it's mostly a lot of work. Boring work. This may be one of the reasons we still have to live with mediocre speakers around us.

A good speaker designer -- like Henry Kloss or Winslow Burhoe -- will do so much voicing work, with so many different speaker/cabinet/crossover variables, that they can predict how a speaker will sound without ever having played music through it.

Anyway, back to 1997. I finally cornered (literally) Henry back in his work area, told him about the article I wanted to write, and asked him what he thought was the secret to designing great-sounding speakers. He scowled (I think it was a scowl, it may have been his "normal" face that day), turned around, walked away 10 feet, and stood there thinking. About a minute later he turned around and said, "Fussing, fussing and fussing." Then he went back to work, without another word.