Transcript (ppt)

CONCEPTUAL
TOOLS
Audio Filter Project
Neil E. Cotter
Associate Professor (Lecturer)
ECE Department
University of Utah
Overview
CONCEPTUAL
TOOLS
• Goal:
Build filter to pass low or high frequencies in audio signal
• Equivalent to bass/treble controls on MP3 player
http://www.guardian.co.uk/music/blog/2009/
dec/21/jazz-purist-found-wynton-marsalis
http://www.thatcable.com/category/
6-35mm-(1-4inch)-Plug-to-Plug/sub
http://salestores.com/gegsdu153w60.html
http://www.ebay.com/bhp/f3-cellphone-watch
http://news-releases.theurbanmusicscene.com/2009/01/27/
pedro-giraudo-jazz-orchestra--el-viaje.aspx
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)
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)