Subtractive Synthesis is the most common type of synthesis
many synthesizers are based on this type of synthesis (Mini Moog, Juno 60, Prophet synths, Arp 2600 etc.)
In subtractive synthesis The tones are generated in this way:
you start with one or more waveforms with a large number of harmonics, and then pass this mix through a filter that removes some of the harmonics to create the desired sound or timbre. This modified tone is then sent to an amplifier that adds articulation to the note by varying its loudness.
The Amplifier and the filter can be modulated by an Envelope Generator and an LFO (Low frequency oscillator)
here is a small diagram on subtractive synthesis
