Live Sound Tech Tip - The Amp/Speaker Connection
By Dennis Kambury

When you're putting together a live sound reinforcement system, you may wonder—when confronted with the dizzying array of specs—just how large a power amp you need to drive your mains. If your speaker cab is rated at 200 watts, your initial assumption might be to match it with a 200-watt amp or less. After all, if you give your speaker too much juice, it'll blow, right? Not really!

While this will certainly work, to understand why more is better, we need to look at how power handling is defined. When you see a speaker that is rated at "200 watts average (program) power," that means it can handle a constant 200-watt signal without failing. A matching 200-watt amp will certainly do this, but the keyword here is "average." That means there will be peaks in the musical program that will be much higher than 200 watts! When these peaks happen, an underpowered amp will respond with distortion—and could damage or even destroy your speakers!

To get the most out of your speakers, both sonically and structurally, it's best to go with an amp rated two to four times the speaker's program rating. Run the amp in the middle of its range—you'll have great headroom, your ears will be treated to a better sound, and your speakers will still respect you in the morning!

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