Crossover

Technology / Home Audio / Crossover: A circuit that divides the frequency spectrum into two or more parts. A crossover acts as a filter, allowing certain frequencies to pass through to the speaker while blocking others. It's the crossover's job to send only high frequencies to the tweeter and only low frequencies to the woofer. (And midrange frequencies to the midrange driver in a 3-way speaker.) A high-pass crossover allows only frequencies above the 'crossover frequency' to pass through, while a low-pass crossover (common in powered subwoofers) allows only frequencies below the crossover frequency to pass through. A 'bandpass' crossover combines a high-pass and a low-pass so that the driver (often a midrange unit) only sees a restricted band of middle frequencies.
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Crossover Slope

Technology / Home Audio / Crossover Slope: The rate at which a crossover circuit attenuates the blocked frequencies. Slope is expressed as decibels per octave. A 6db per octave crossover reduces signal amplitude level by 6db in every octave st MORE

Built-In Crossovers

Technology / Home Audio / Built-In Crossovers: Frequently used to limit the high-frequencies reaching a subwoofer, a low-pass filter crossover allows only frequencies below the crossover point to be amplified. A high-pass crossover allows only fre MORE

Butterworth Crossover

Technology / Home Audio / Butterworth Crossover: A type of crossover circuit utilizing low-pass filter design characterized by having a maximally flat magnitude response, i.e., no variation in the amplitude response in the domain of the passband. MORE