Editing Audio crossover (section)

====Mixed order====
Crossovers can also be constructed with mixed-order filters. For example, a second-order low-pass filter can be combined with a third-order high-pass filter. These are generally passive and are used for several reasons, often when the component values are found by computer program optimization.  A higher-order tweeter crossover can sometimes help to compensate for the time offset between the woofer and tweeter, caused by non-aligned acoustic centers.