A speaker system can cost as little as $35. Or as much as $350,000. As a normal person, you probably have just one question about speakers that cost as much a Ferrari: What. The. Hell.
How Speakers Work
Especially when you consider just how simple the overall mechanism behind a standard speaker is: It moves air. Essentially, what happens in a speaker—loudspeaker, to be technical—is that the alternating current from an amplifier runs to the speaker and through the voice coil (which is just, wait for it, a coil of wire) turning the coil into an electromagnet. That, in turns, creates a magnetic field between it and the permanent magnet in the driver. As the current alternates between positive and negative, the magnets are attracted and repulsed, moving the cone back and forth. Voila, it emits the soothing sounds of Bach or Korn. (Driver diagram from Wikipedia's unusually exceptional loudspeaker article.)
But that's probably not quite what you think of when you hear "speaker." You're probably thinking of a box with a circle thing and maybe a hole in it. That's actually a loudspeaker system, and it actually has more than one kind of speaker inside of it, called drivers. That's because the driver tuned to deliver high frequencies—a tweeter—ain't so good at delivering bass, which is why you need a woofer or subwoofer (low and lower). And then you've got mid-range speakers—for mid-range sounds—in higher-end systems. Your average GENERIC SPEAKER COMPANY set skips this middleman. So generally two or more drivers are stuffed in a box or cabinet, called an enclosure.
Lovely, but that doesn't explain what separates these $107,000 YG Acoustics Anat Reference II speakers from the $50 Logitech Z-2300s on my desk—which are even THX certified. So, we enlisted some help: Cnet's Audiophiliac Steve Guttenberg, who lives and breathes speakers ranging from the sensible to the ludicrous, and Paul DiComo and Matt Lyons, speaker guys who came from Polk and are now at Definitive Technology.
If you read our profile of Audiophile Maximo Michael Fremer "Why We Need Audiophiles," it probably won't surprise that when initially asked simply, "What the difference between ten dollar speakers and ten thousand dollar speakers?" the Definitive guys' initial answer was, "Well, it ought to be that they sound better." Even Steve told us, "You can't apply a Consumer Reports kind of index to something that's as subjective as audio quality."
No, but seriously.
The Goal of a Loudspeaker
A speaker's ultimate goal is "to sound like reality"—the elusive dragon that every audiophile chases—so on a broad, not-very-useful level, how close it comes to matching that reality is the difference between good and bad, expensive and cheap speakers. To be slightly more technical, the "spec" is clarity: The lower the distortion of the original sound it recreates, the better the speaker. In fact, basically every other spec, every confusing number you read on the side of a box is actually totally meaningless, according to both Steve and the Definitive guys. Steve singles out watts as "one of the more useless specifications ever created." If you have to look for a number when buying speakers, Steve said one that's "kind of useful" is sensitivity/efficiency, which would be something like 90dB @ 1 watt, which relates how loud a speaker will play at a given power level.
But when pressed, there are a few qualities Paul and Matt from Definitive singled out in amazing speakers—what they call the big three:
• More dynamic range, or simply the ability to play louder without sounding like trash as you crank the volume. With good speakers, you want to keep cranking it up, like accelerating a fast car.
• Better bass. That doesn't mean louder, "but better." It's more melodic, and not muddy—you can actually hear individual notes, an upright acoustic bass being plucked.
• "A very natural timbre." Timbre is the "tone color" or how natural the sound is—if you played the voice of someone you know on a speaker with excellent timbre, it would sound exactly like them. Or if two different instruments play the same note, you'd be able to tell them apart very easily and cleanly.
Beyond that, what audiophiles are looking for—which Mahoney alludes to in the audiophile profile—is a speaker's ability to create an image, the picture. That is, its ability to create a sense of three-dimensional sound. The defining problem of designing speakers, say the guys from Definitive, is that "physics is dogmatic." So every speaker is built around a set of compromises.
To put that in some concrete—rather than seemingly religious—terms, you can't have a small speaker that sounds good. So one defining quality of six-figure speakers is that they are large. They have bigger woofers and tweeters. More surface area means better sound. There are also simply more drivers—every driver you add is like when you add another string to a guitar, to create a better-nuanced sound. So, for instance, a $300 speaker from a "quality manufacturer" you'll get a 5 1/4-inch woofer and a 1-inch tweeter. A $3000 pair of speakers might have two 5 1/4 mid-range drivers and then a 10-inch woofer.
Build quality is the other thing. A "dead box," or an enclosure that doesn't create any sounds of its own—since that's distortion—is key and something that costs a lot of money. You just want sound from the drivers themselves. The quality of the woofer and tweeter themselves, obviously, comes into play—their ability to handle more power, since that's what translates into volume.
At the extreme end, Steve says, they can just handle more power without breaking—as the copper wire inside heats up, it can deform or melt, and the driver gets messed up. Pricey speakers don't do that. In terms of exotic materials or construction, Steve mentioned ribbon tweeters, which are only in the highest-end speaker systems—they're "literally a piece of aluminum foil that's suspended between magnets that vibrates back and forth" producing excellent clarity. Better speakers also have intricate dividing networks to make sure the right signals go to the right place—they get more complicated as the price goes up.
So how much do you have to spend to get a good system in the eyes (ears?) of an audiophile? Definitive recommends $1000 for a home-theater component setup. (In other words, don't buy a home theater in a box.) You can also get a pretty decent pair of "neutral, natural sounding" speakers for $300—they "won't knock your ass" and won't be great as some things, but they'll be alright. There's no magic one-size-fits-all speaker system, however. It depends on the room and the situation. (If your couch is against a wall, skip the 7.1 surround, says Steve.) Heavier speakers tend to sound better than lighter ones, though that's not an absolute.
But what's the upper limit? Well, there isn't any. Paul from Definitive said he heard these $65,000 Krell Modulari Duo last month and "was mezmerized." It's like wine to oenophiles, Paul said. As Steve puts it most simply: "To people who are into it, it's worth it."
Still something you still wanna know? Send any questions about speakers, KoRn or John Mahoney's secret Britney shame to firstname.lastname@example.org, with "Giz Explains" in the subject line. Big thanks to Steve from Cnet and Paul and Matt from Definitive Technology!
Listening Test: It's music tech week at Gizmodo.