What’s a Crossover?
Chances are if you’re reading this, you already know what a crossover is – and you know that you need one. But if you are new to multi-way PA systems, here's a brief overview. Loudspeakers (which we call transducers) convert electrical signals into sound waves. And no matter how well a transducer is designed or made, it simply cannot reproduce the entire audio spectrum all by itself. Low-frequency sounds tend to push a transducer to the maximum, making it impossible for that same transducer to reproduce the treble content with the sound quality it deserves. (Try singing high falsetto next time you’re bench-pressing your limit!)
That's why high-quality sound systems use multiple speakers (woofers and tweeters) to spread out the work. While the woofer (usually the larger transducer) does all the heavy lifting, the tweeter can easily handle the high-frequency content. Three and four-way systems distribute the work even more, allowing the individual transducers to reproduce the frequency range for which they were designed. It is the crossover’s function to divide these tasks between the various amplifiers and transducers.