Audio Filter Project

Neil E. Cotter!Associate Professor (Lecturer)

ECE Department University of Utah

CONCEPTUAL TOOLS!

Overview

•   Goal: Build filter to pass low or high frequencies in audio signal

•   Equivalent to bass/treble controls on MP3 player

CONCEPTUAL TOOLS!

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Overview

•   Goal: Build filter to pass low or high frequencies in audio signal

•   Equivalent to bass/treble controls on MP3 player •   Each group of students will design/build low-pass filter (more bass) or high-pass filter (more treble)

CONCEPTUAL TOOLS!

Overview

•   Goal: Build filter to pass low or high frequencies in audio signal

•   Equivalent to bass/treble controls on MP3 player •   Each group of students will design/build low-pass filter (more bass) or high-pass filter (more treble) •   Theory first:

Sound waves = sums of sinusoids (Fourier theory) Complex numbers can represent sinusoids (Phasors) Electronic components alter sinusoids— resistors, inductors, capacitors

Filter design = sinusoid analysis (circuit theory)

CONCEPTUAL TOOLS!