An extension of the Linkwitz-Riley crossover filters for audio systems and their sampled data implementation

Loud speaker drivers are not able to operate over the entire audio spectrum. The standard response to this limitation is to use multiple drivers designed to operate over selected contiguous frequency spans such as low-pass, band-pass and high-pass. Crossover filters partition the audio spectrum into appropriate spectral bands matched to the bandwidth of the multiple speaker drivers. For many years, the standard crossover filters that perform the spectral partition has been the Linkwitz-Riley (L-R) Filter [1]. In this paper we review the structure of the L-R filters, extend their design to any order crossover, and present their efficient DSP implementations.