Euphony, cacophony, monophony, homophony, polyphony, heterophony — musical sound has many guises.

But let’s start with the basic building block: noise. Mostly it’s nasty:

A sound of any kind, esp. a loud, harsh, or unpleasant one.
(Oxford English Dictionary)

Though it has had its good side, too:

It ceas’d: yet still the sails made on
A pleasant noise till noon,
A noise like of a hidden brook.
(Coleridge: The Rime of the Ancient Mariner)

What’s certainly true is that there’s much too much of it, both pleasant and unpleasant, in our 21st century urban environment — it’s become a pollutant.

So, before we start to explore the ‘phonies’ and harmony and dissonance, a bit of noise analysis.

P.S. Did you think white was the only colour noise came in? Think again!!