Treffer: Digital filter implementation for an audio analyzer

In the past, the audio analyzer has been implemented with a bank of analog filter circuits. In the one-third octave audio analyzer, 32 independent bandpass filter circuits are required. Each filter is designed to allow a specific band of frequencies to pass, and suppresses all others. With the advancements of modern science and technology, many analog systems have been replaced by digital systems due to better performance reliability and lower production costs. The purpose of this thesis was to design and build an audio analyzer using digital techniques. Two of the most promising techniques were analyzed and their performances compared. Each technique was studied in terms of: (1) Method of filtering. (2) Degree of simplicity in filter implementation. (3) Advantages and disadvantages of using the filters. (4) Possible applications. One technique was selected and implemented with hardware to perform as an audio analyzer. Software was also designed to control the filtering operations. Tests indicated that signal processing using digital techniques resulted in better performance than that of it's analog counterpart. ; California State University, Northridge. Department of Engineering. ; Includes bibliographical references (pages 63-66)