October 2021

Are You Part Of The 80 Percent?
Roger Skoff writes about performance measurement.
Article By Roger Skoff

  Just a few days ago, some guy wrote on one of the social media that he had come across some thousand dollar speakers that were eighty percent as good as ten thousand dollar ones.

What does that mean? Do you know? Does he?

Could it be that the less expensive speakers have only eighty percent of the frequency range of the more expensive ones? Or that their frequency response curve is only eighty (80) percent as "flat"? If so, which twenty (20) percent of the frequency ranges are being shorted? Bass, treble, mid-range? Can any of those be compromised and still have speakers that sound good?

Maybe the difference is one of relative sensitivity. Maybe the thousand dollar ones are only 80 percent as loud per watt of input power as the ten thousand dollar ones. If that's the case, so what? The way sound works, "twice as loud" (the result of getting twice as much current or twice as much voltage [twice as many watts] from the amplifier) is only 3dB louder from the speaker, which, perceptually, is not very much at all. (A change of 10 dB is accepted as the difference in level that is perceived by most listeners as "twice as loud" or "half as loud". To produce an increase of +10 dB you need to increase power (Watts) by a factor of 10.) Given all that; how much is 80 percent of 3dB, and how much difference can it possibly make?

It's the same thing with power handling capacity: With even not-very-sensitive speakers like my Acoustats having a sensitivity of greater than 80dB @1Watt/1Meter, it doesn't take much power for normal listening levels. Most listening, by most people, to most music, most of the time, is at well less than one Watt of input power. Since 80dB is fairly LOUD, so… except for lease-breaker listening or the occasional big orchestral crescendo, power handling isn't really an issue.

So what does "80 percent as good" really mean?  It depends on what you mean by "good", and that may be different from one person to another. For example, if, when you listen to a vocal recording, all you really care about is the words and the rest doesn't much matter, a five dollar speaker might very well be good enough for you: It will play exactly the same words as the ten thousand dollar High-End speaker pair and, if it has sufficient clarity to allow you to hear and understand every one of those words, for your listening purposes, it might be just exactly as good as the more expensive alternative.

What, though, if you could only understand eighty percent of the words? Could you say that it was 80 percent as good? I don't think so.

Only listening to the words of a song is obviously an extreme example, but only being able to understand eighty percent of them is not: For many years (and probably even still today), whether, and to what degree you could understand the spoken words behind the music on Pink Floyd's Dark Side of the Moon album was, for good reason, considered to be one of the supreme tests of speaker and overall system performance.

As to absolute standards of performance – particularly quantifiable ones – if such really exist, except on the most basic levels, I doubt if they're of much universal importance. Even on the same system or the same piece of music, different people listen for different things – frequency response, clarity, dynamics, harmonic structure, transient attack and decay, or any of a whole host of other characteristics that all combine to create the musical experience. And even the same person may listen for different things at different times or on different pieces or kinds of music.

Even so, while how people rank their importance may differ, there really are certain levels of performance that can be clearly identified as systems or recordings get better.

Even the most basic playback device – a transistor radio, for example, or the tiny speaker in a cellphone – will let you hear the words of a song to at least some reasonable degree, and to get an idea of the tune behind it. The next step (a boombox, perhaps) adds the underlying "beat" or rhythm of the music and starts to let you tell which, and perhaps how many kinds, of instruments are playing.

Higher "fi", and up into stereo and modern immersive Dolby Atmos/etc, brings you the ability to identify different but similar-sounding instruments (a clarinet and an oboe, for example, or a violin and a viola) and, if it's stereo, to get an idea of how many instruments or singers are performing and where they are placed, right to left, across the front soundstage. (Editor's Note: The 'next generation' of immersive music creation, only now becoming more available to musical artists, will celebrate the next chapter of recorded musical performances. The legacy stereo format came about almost 100 years ago and continues to served the music business well.)

All of those things are cumulative in effect and each step better – even given individual tastes and listening preferences – is easily recognized as including and being an improvement over the last. The last stage, though, is not simply one of "better", but of a whole new kind of information – three-dimensionality and the presentation of soundstage, ambience, and dare we say a truly immersive experience.

Surprisingly, while this is a hugely different kind of experience, the amount of improvement necessary to achieve great subjective improvement  may be objectively tiny – certainly not twenty percent or anything like it, but more like, by actual measurement, just one or two percent or even less.

To understand this, imagine a lock and a key. If the key is just a few thousandths of an inch too thick, it may not be possible to get it into the lock at all. And if the key's profile differs from the internal profile of the lock by even just a little, you may be able to insert it, but you won't be able to turn it and open the lock. It's the same with high-end audio: tiny changes can make huge differences in perceived performance and listening pleasure.

Eighty percent of great performance may actually be unlistenable, regardless of the fact that that guy on the internet meant his description as a compliment to a thousand dollar speaker system as compared to one at ten times the price. In reality, though, percentages measured or subjective, are poor tools for describing audio performance. What's important at any price point is that, when you listen, you...

 

 

Enjoy the music!

Roger Skoff