Audio Filter Project

Neil E. CotterAssociate Professor (Lecturer)

ECE DepartmentUniversity of Utah

CONCEPTUALTOOLS

Overview

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

• Equivalent to bass/treble controls on MP3 player

CONCEPTUALTOOLS

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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)

CONCEPTUALTOOLS

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)

CONCEPTUALTOOLS