FIR and IIR Filters for Sound Equalization Systems

Subject Areas : Majlesi Journal of Telecommunication Devices

Teimour  Tajdari ¹ (Department of Electrical Engineering, Velayat University, Iranshahr, Iran.)

Received: 2020-02-27 Accepted : 2020-02-28 Published : 2020-06-01

Keywords: bilinear method, IIR Filter, audio equalizer, FIR filter, window method,

Abstract :

IIR and FIR filters are widely used in digital signal processing. The choice of one of these methods depends on the design requirements. In this paper, the two filter design methods are compared in audio equalizer system design. Audio equalization systems are used in electric guitars, pianos, and other electric instruments. It is also an integral part of audio players, audio amplifiers and sound recording systems. The design includes a six-band amplifier that can be used to modify the signal amplitude over the entire audio frequency spectral range. Digital filters were transformed from Chebyshev analog prototypes using Bilinear Transformation Procedures on IIR filters. The Window method was used to design the FIR filter with the same specifications as the IIR filter. The results show that IIR and FIR can be used to design equalizer systems. But one has advantages over the other. Filters can be designed with low order IIR methods, but the FIR requires high order filter designs. On the other hand, in the FIR filter design method, the linearity of the phase response is much better.

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