Audio is no less immune to the sort of mild lies and partial truths found in the HDTV world. As I discussed in the HDTV edition of MMM, cutting through these fabrications is the key to understanding what really matters.
Before you spend any money on audio, check out this list for what's important, what's not, and what's just total misdirection.
'I won't hear a difference'
This is, by far, the biggest myth. Whenever the topic swings to audio, a disturbingly high percentage of people say some version of "I won't hear the difference." The fact is, people don't trust their ears like they do their eyes.
What I've found, as have others who've studied it far more extensively than I, is that nearly everyone can hear a difference. Compare two speakers or headphones back to back (figuratively) and I'll put money that you'll hear a difference.
Is the difference between different amps, DACs, and so on more subtle? Absolutely, but it's there. With nearly all audio equipment, the performance differences are objectively measurable.
So the issue is that people think they won't hear a difference, so they don't bother spending money on audio, leading to people thinking there's no point in spending money on audio, because all they've heard is bad audio. A vicious circle.
If you're expecting to not hear a difference, you probably won't hear a difference. Keep an open mind, and trust your ears.
Wattage ratings are often rubbish, in more ways than one. Watts are how powerful an amp, or the amp portion of a receiver, is. Technically, it's how loud it will make your speakers, but the truth is far more complicated. For one, the 100 watts from one manufacturer isn't the same 100 watts from another. A cheap 100-watt receiver may produce 100 watts driving one speaker at one frequency, but only manage to put out a fraction of that when running multiple speakers playing real music.
The other bit of truth is that you need to double the wattage to hear an appreciable difference in volume. Comparing a 100-watt receiver to a 105-watt receiver? If it's the same brand, it's probable it's got the same amplifier inside (just rated different). It's possible for two amps with slightly different wattage ratings to sound different, but all things being equal, they won't produce a different volume. If things aren't equal, like you're comparing an expensive amp and a cheap receiver, then all bets are off.
When it comes to receivers, the fact is nearly all will drive your speakers with little problem. If you want more volume, or you experience clipping/distortion, then a more powerful amp may be needed. A better amp will make your speakers play louder and sound better, but it won't make bad speakers sound like good speakers.
Speaker wattage ratings
Many speakers have a "maximum wattage rating" on the back. Treat this as a "minimum wattage rating." You are far more likely to damage a speaker giving it too few watts and trying to play it too loud. High-end amplifier companies make amps with more than 1,000 watts, and you could plug in a $50 speaker into it with no problem. Though why you'd want to...
A certain four-letter company has done an excellent job perpetrating the myth that small speakers can perform just the same as large speakers. Though systems with tiny satellite speakers and a sub can sound OK, they can't overcome physics. This doesn't mean you need massive towers to get good sound, but it does mean that a pair of well designed bookshelf speakers will almost always sound better than most tiny satellite/sub systems, even if the latter are more expensive.
Subwoofers can go anywhere
This one is somewhat true. Low-frequency bass sounds are difficult to localize. So putting a sub on a side wall or away from the main speakers generally isn't a problem. Two things:
- With cheap subwoofer/satellite speaker systems, the subwoofer is often tasked with frequencies far higher than a traditional subwoofer. This can often mean it has to reproduce the low end of male vocals and some instruments. In this case, it is very easy to localize. Check the owner's manual of any inexpensive speaker system to see what the company recommends.
- Though it's possible to put a sub anywhere, it will sound better/louder in certain places. Putting a sub against a wall will increase output by around 3 dB (a noticeable increase). Putting it in a corner can increase output by 6 dB (a significant increase). There are also places in the room where you'll get a flatter frequency response, but that gets pretty technical, and could fill an article all its own.
20Hz to 20,000Hz
Many speakers and headphone claim a frequency response of 20Hz (really deep bass) and 20,000Hz (well above the hearing of anyone reading this article). In theory, this is the range of frequencies the speaker is capable of reproducing. Much like the wattage rating, how this is measured varies radically from each company. It also tells you little about what a speaker actually sounds like. A clock radio may be able to reproduce 20kHz, but if it does so 15 dB quieter than what it produces at 1kHz, you won't be able to hear it. That's the real important aspect. If the speaker is -3 dB at 40Hz, chances are the speaker won't sound like it has as much bass as a speaker that's -3 dB at 20Hz.
This all assumes honest, well-measured numbers by the speaker manufacturer, which is rarely a given.
In fact, this is so inaccurate that unless there is something really different (like "200Hz to 15,000Hz), ignore it completely. Speaker measurements can tell you a lot about how a speaker sounds, but numbers claimed by a company like this are useless.
And I hate to disappoint, but I'm not going to say the same about audio cables...to a degree. Analog transmissions can degrade over distance, and are sometimes susceptible to interference. In either case, it's not nearly as much as the cable manufacturers would lead you to believe. With speaker signals, for example, you're typically talking volts on the speaker cable versus microvolts of interference. Does this mean you need to spend a billion dollars on some super-ultra-silver-wire-thingie and little holders to keep the wire off the floor? No (unless you really want to).
Buy decent speaker cable, and decent analog audio interconnects (if you need them). What's "decent"? I'll leave that to your wallet. Don't go nuts, and if the salesman gives you some magical "percentage" you should spend on cables, remember he's the same guy telling you to buy a $150 HDMI cable. As in, spend a lot less.