Often when trying to understand sound waves, it's useful to visualize a spring or a slinky (remember those?) If you push a spring from one side, a pulse is created. This pulse travels through the spring causing the hoops of...

Suppose that same slinky is now stretched out horizontally and a pulse is introduced by vibrating the first coil up and down. A pulse of energy will be carried through the slinky from left to right and the coils will...

A simple wave goes through a journey of a positive peak and negative troughs before repeating. A wavelength is a measure of the distance between the two peaks or troughs in a wave.

Amplitude (or intensity) is the strength of a sound wave, which we interpret as loudness or volume. In graphical form, amplitude usually appears on the y-axis. Audio engineer's express amplitude as decibels (dB). Later on, in this lesson, we'll look...

Phase is defined as how far along its cycle a given sound wave is. Because sine waves are cyclical and progress through regular cycles of peaks and troughs we can measure phase in terms of degrees, where 360 degrees comprise...

When we are speaking about sound, it is essential to have some way to express the pitch. If sounds are vibrations traveling through the air as sound waves, the frequency is the speed at which these waves vibrate. Moreover, that...

If you play a certain note on an instrument, the instrument will produce the frequency of the note, but it can also other generate other frequencies and sounds (overtones and noise). The fundamental frequency isis the most pronounced frequency of the note...

Not only do we hear the fundamental pitch, but we also hear the higher frequencies called harmonics and overtones. A harmonic is a multiple of the fundamental frequency. An overtone is any frequency resonating above the fundamental frequency NOTE: An...

The harmonic series is an ordered set of frequencies which are integer multiples of a fundamental frequency. A visualization of the harmonic series The first harmonic is the fundamental frequency and the second harmonic is the...

Even order harmonics of a fundamental frequency are frequencies that are 2, 4, 6 times the fundamental. If we look at our harmonic series example again, the even order harmonics of 440 Hz are 880 Hz 1760 Hz 2640 Hz 3,520...

Odd order harmonics of a frequency are frequencies that are 3, 5, 7, and so on times the fundamental. If we look at our harmonic series example again, the odd order harmonics of 440 Hz are: 1320 Hz 2200 Hz 3080...

Noise is a sound component which is captured that part of the inherent musical sound. It can be defined in two ways: any unwanted sound (as in clipping, electrical hums etc) sound which has no discernible repetitive wave pattern (like a hiss or...

Timbre (pronounced "tam-ber") is the tonal character of a pitched sound given by its overtones So even though two instruments can play the same pitch, they sound different due to the complex waveforms created by their unique combination of overtones. For...

A transient is a momentary, high amplitude peak at the beginning of a sound; the initial burst of energy. In a drum hit, the transient is the initial "tak" or "thud" of stick hitting the drumhead. On a guitar, it...

A sound envelope is the way the amplitude of a sound unfolds over time. Along with the timbre, the sound envelope helps establish a sound’s unique individual quality. A sound's envelope is divided into four sections: Attack Decay Sustain Release...