First of all let's get rid of those
uninteresting already
defined
spectrums, mainly of light, by doing this:
In general, a
frequency spectrum is a range of frequencies that have been analysed to reveal the characteristics of each frequency (amplitude and sometimes phase as well). Any decent
amplifier of today has equalizing features that are actually a way of subclassing the entire frequency spectrum of
the sound coming out of your speaker into smaller spectrums and change their
characteristics seperately (altering
bass+
treble, or having eg. 16 different bands -
WinAmp feutures 10 bands)
Spectrum analyzers are being used frequently by
electronic engineers and can
determine behaviour of signals. They output frequency spectrums of the signals they recieve.