Sound

• Sounds are sensations by the stimulation of the organ of hearing by vibrations transmitted through matter.
• Pitch - refers to the perceived frequency of a sound wave.
• Loudness - refers to the volume or intensity of a sound, how loud or soft it is.
• Timbre - refers to the quality of a sound, its tone color.
• Harmonic Content determines the waveform of the sound signal when graphed as a function of time
• Vibrato is the periodic changes in the pitch/frequency of the tone.
• Tremolo is the 46 periodic changes in the amplitude or loudness of the tone.
• Sounds higher than what humans can hear are called ultrasounds.
• Sounds lower than what humans can hear (below 20 Hz) is called infrasound.
• Doppler Effect - The pitch of sound changes as the position of the source of sound changes.