PSYCH 3A03 Lecture Notes - Signal 1, White Noise, Psychophysics

• School: McMaster University
• Department: Psychology
• Course: PSYCH 3A03
• Professor: Paul Faure

Document Summary

Damped sinusoidal motion: a free vibration in response to a single input force. Standing waves develop as a result of continuous forced vibrations from external force. Most acoustic events result from forced or driven vibrations. Objects naturally vibrate at their natural frequency. Filters perform a frequency selective attenuation on a sound. Filters work on both simple sounds and complex sounds. The cutoff frequency of a filter is the frequency where the signal energy decreases by one half (i. e. -3db) The fc is the frequency where the output energy of the gilter drops to of the input energy. Band pass and band reject fiters have both a low pass and high pass cutoff frequency. Filter cutoff frequency defines power (-3db) point. The amount of attenuation is known as the roll-off rate. Filter roll-off rate is measured in db per octave (=slope) Roll-off rate is in decibels of attenuation per doubling of frequency starting from the filter"s cutoff frequency (fc)