Time alignment

 In a multiple-driver loudspeaker system, it is important that the time delay of each driver and its associated crossover network be the same to preserve accurate transient response, i.e., the high frequencies and low frequencies reach the listener’s ear at the same time. Crossover networks have different delays depending on the frequency range they cover, as do speakers; woofers have more delay than tweeters. One can place tweeters farther from the listener, or build time-delay into the high-frequency signal path. See transient response.