Using Interpolated FIR Technique for Digital Crossover Filters Design

Digital filters design is an important aspect of the audio processing. They are used in several applications and the key point is not only the achieved final audio quality but also their computational complexity. In this context, the use of Interpolated Finite Impulse Response (IFIR) filters is proposed for the optimized implementation of a digital crossover network. In particular, the structure can be viewed as an analysis filter-bank that can be optimized introducing IFIR filters that allow to reach very narrow transition bands, with low computational complexity and linear phase, avoiding ripple between adjacent bands. Starting from a real-time implementation of the proposed crossover network, several experiments have been conducted to prove the effectiveness of the proposed approach in terms of computational complexity and obtained audio quality.