Computer Science 1033A/B Lecture Notes - Lecture 11: Hertz, Sound Card, Alger Hiss

• School: Western University
• Department: Computer Science
• Course: Computer Science 1033A/B
• Professor: Vivi Tryphonopolous

Document Summary

What is sound: sounds are pressure waves of air, visualize a sound as a series of recurring waves called a wave form, voice muscles vibrate and cause the air to moved thus cause sound (a series of waves) The nyquist limit: this rule says you must take at least two samples for every cycle of the wave. If you take less than two samples,you will get a completely different sound wave: sample rate= number of samples we take per second of audio or number of times per second the wave form is measured. Typical sample rates: voice only (telephone quality) =8khz, am radio quality= 11. 025 khz, fm radio quality = 22 khz, cd quality music= 44. 1khz. Overlap two or more pieces of audio find words you want to edit out and cut them from the waveform: modify the volume. Hiss reduction- noise within a given frequency range.