“Let’s get real, real gone for a change.”—Elvis
As Plato mentioned in The Sophist and thousands of art historians have noted in the years since, Greek sculptors distorted the human figure by enlarging the head and shoulders. They did it on purpose. If they didn’t, when viewed from below, it would look wrong. Poets—real ones, I mean—distort smaller truths in order to create larger ones. Every type of musical temperament is a means of distorting the relative sizes of sub-octave intervals—or, in fixed-pitch instruments, creating compromises—in order to create a pleasing result. Human interaction is all about distorting the truth: If you always told everyone what you’re really thinking, you’d be beaten to death by the age of 9.
Except for medicine, transportation, civil engineering, and the mixing of drinks, every human endeavor involves some degree of distortion, sometimes unexpected but just as often intentional and well-accepted—and sometimes naturally occurring.
Any music recording, of even the simplest piece, contains an enormous amount and variety of information: What pitches did the performer(s) produce? What were the shapes of those notes, in terms of the proportion of attack, sustain, and decay components in each one? What were the temporal relationships between the notes—the rhythm and the pacing? In what sort of space was the music performed and recorded? How close were the performers to the listeners/microphones? What were the timbral colors of the sounds their voices and instruments produced? What were their textures? How big was the sound they created? How forceful? How loud at its loudest and soft at its softest? What other audible things were going on—passing cars, coughing listeners, creaking seats, sighing babies—when the recording was made? Every piece of playback gear ever made distorts at least one of those things. Probably more.
And you can believe me when I say: Unless you live in a concert hall, unless your ears are truly indefatigable, you do not want a playback system that is 100% free from distortion. To paraphrase my friend, audio critic Steve Guttenberg, why in God’s name would you want to hear a perfect reproduction of a concert grand piano in a room in which the real thing would sound terrible? (And do please bear in mind that that can be said of 99% of all the rooms on the planet.)
Like most people, you probably have an internal checklist, whether subconscious or not, of the distortions you wish to be free from and those you tolerate or perhaps embrace. God knows I do. As people who know me have remarked, in these pages and elsewhere, I tend to listen to recorded music at playback levels slightly lower than the average, certainly lower than the stuff would have sounded in real life. That too is a distortion, one that makes music more lifelike in the aggregate to me. Your own checklist is surely different from mine and from those of your friends. It’s useful to note that the intricacies of human perception and the frailties of the mechanisms we use to perceive the world render a comprehensive inventory of distortions unreliable.
That said, certain distortions of sound are always bad, always to be avoided if possible. At the top of that list are mechanical limitations that prevent playback gear from working as intended (footnote 1)—a chipped or severely worn stylus that can’t stay in the groove, a tonearm whose bearings won’t allow it to follow the groove, a loudspeaker whose voice coil is in physical contact with the sides of its gap, and so on—and electrical phenomena that overlay music’s complex wave with nonlinear, non-sinusoidal waves. (I fondly remember an event from my early 20s when a technician friend put my Marshall guitar amp on his test bench and we watched it turn every signal that came its way into something that looked like a sawtooth wave. It was pretty cool, but not something we should want from our hi-fis.)
Throughout the history of audio journalism, a number of technically minded, self-righteous, or Puritanical writers—the founder of this magazine included—have delighted in ridiculing those, including me, who accept that the evaluation of playback gear is, at its core, a discourse on the distortions we find most or least acceptable. It is their inflexibility that deserves ridicule: We have been right all along.
Put another way: “How much distortion does this thing have?” is the wrong question, and “What kind of distortion does it have?” is only slightly righter. The most important question we can struggle to answer is, “In what sort of setting and to what sort of listener does this thing offer a soul-satisfying degree of musical realism sufficient to justify its expense?”
If Acoustic Research founder Edgar Villchur was truly an audio-industry visionary, and if his work was as influential as many of my colleagues claim, why is it that products embodying his two most conspicuous contributions to our field—the acoustic suspension loudspeaker and the suspended-subchassis turntable—are now as rare as tooth fairy sightings in West Virginia?
Consider the acoustic suspension loudspeaker, in which a woofer is designed and manufactured with a surround and spider so loose that the drive unit’s free-air resonance is impractically low, and its ability to restore cone position in the absence of a signal is essentially nil—unless and until that driver is fastened to the baffle of a smaller-than-average sealed box such that the springiness of the air trapped within supplies the necessary restorative force and raises the free-air resonance to a usefully higher yet lower-than-average frequency, all in the interest of providing deep bass extension from a less-than-large loudspeaker.
In that light, acoustic suspension seems a perfectly apt name: Villchur described his development process by saying he cut away part of the spider from a third-party driver—according to legend, this was a Western Electric 755 full-range unit—and removed entirely the cone’s integral surround, replacing it with a fabric surround made from mattress ticking. (He credited his wife with creating the necessary pattern.) Thus modified, the driver would have no suspension of its own, so an air spring would have been required for the thing to work at all.
A few factoids about acoustic suspension:
• Acoustic suspension loudspeakers are inefficient—more so than any other means of loading a dynamic drive-unit, be it reflex loading, aperiodic loading, isobaric loading, Karlson loading, transmission-line loading, quarter-wave pipe loading, or, especially, horn loading. And that’s a shame, because, all other things being equal, as efficiency goes down, distortion goes up. Way up.
• Another consequence of the inefficiency of acoustic suspension loudspeakers is their need for a higher-powered amplifier, something Edgar Villchur dismissed by noting that, at the time he created his design—which more or less coincided with the introduction of solid-state amplification—power was cheap enough to not be a concern. Here I must once again ask a question that I posed in this space just a few issues ago: Since when is wastefulness considered a hallmark of good engineering?
• In the 1960s, noted loudspeaker designer Paul Klipsch, whose degree was in electrical engineering, began appearing in public wearing a lapel pin bearing the word Bullshit, sometimes tucked underneath his lapel, sometimes not. Word has it that the claims made for the acoustic suspension principle by Edgar Villchur, whose degrees were in art history and education, were the original target of that informal campaign to rid the world of nonsense. (Also according to legend, the two men buried the hatchet after a while.)
In the most recent edition of our semiannual Recommended Components feature, a total of 84 loudspeakers were listed. Of these, only three are sealed-box designs—which in the decades before Edgar Villchur went into the loudspeaker business were simply called infinite baffle speakers. They are the Magico S5 Mk.II, the Graham/Chartwell LS3/5a, and the Klipsch Heresy. Of the three, only the Magico is described by its manufacturer as an acoustic suspension design. (The Klipsch offers very limited bass extension from a 12″ woofer—a combination of qualities opposite to those claimed for acoustic suspension loudspeakers—and according to Derek Hughes, who engineered its drivers and crossover, the Graham/Chartwell LS3/5 and variants “would not be considered acoustic suspension,” adding that the BBC referred to the speaker only as “closed box: they kept away from commercial descriptions.”)
Footnote 1: An exception would be the very first compact disc players of the early 1980s, which sounded wretched when used as intended. They were perverse in the sense that tobacco—which, when used as intended, is lethal—is perverse. Oh well.