User Guide
60
English
Tone
Musical sounds consist of several different, related pitches occurring simultaneously. The
lowest is referred to as the ‘fundamental’ pitch and corresponds to the perceived note of the
sound. Other pitches making up the sound which are related to the fundamental in simple
mathematical ratios are called harmonics. The relative loudness of each harmonic as compared
to the loudness of the fundamental determines the overall tone or ‘timbre’ of the sound.
Consider two instruments such as a harpsichord and a piano playing the same note on the
keyboard and at equal volume. Despite having the same volume and pitch, the instruments still
sound distinctly different. This is because the different note-making mechanisms of the two
instruments generate different sets of harmonics; the harmonics present in a piano sound are
different to those found in a harpsichord sound.
Volume
Volume, which is often referred to as the amplitude or loudness of the sound, is determined by
how large the vibrations are. Very simply, listening to a piano from a metre away would sound
louder than if it were fty metres away.
Volume
A B
Having shown that just three elements may dene any sound, these elements now have to
be realised in a musical synthesiser. It is logical that different sections of the synthesiser
‘synthesize’ (or create) each of these different elements.
One section of the synthesiser, the Oscillators, provide raw waveform signals which dene
the pitch of the sound along with its raw harmonic content (tone). These signals are then mixed
together in a section called the Mixer, and the resulting mixture is then fed into a section called
the Filter. This makes further alterations to the tone of the sound, by removing (ltering) or
enhancing certain of the harmonics. Lastly, the ltered signal is fed into the Amplier, which
determines the nal volume of the sound.
Oscillators Mixer Filter Amplifier
Additional synthesiser sections - LFOs and Envelopes - provide further ways of altering the
pitch, tone and volume of a sound by interacting with the Oscillators, Filter and Amplier,