Date Added: May 2011
An analog active filter can not provide a very sharp cut-off for both higher and lower frequency component, while a Digital Signal Processor (DSP) using digital filter effectively reduces the unwanted higher or lower frequency components within an audio signal. In this paper, the authors present the design and implementation of non real time and real time digital filter for audio signal. Experimental results indicate that digital filters including low-pass, high-pass and band-pass effectively eliminate both low and high frequency components contained in human voice, providing high quality voice. The performances of these implemented digital filters are evaluated both by listening the filtered output and also by analyzing the frequency response curves.