Novation Circuit Mono Station, User Manual

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providing changes in the character of the sound which can evolve over time. Because LFO s’
and Envelopes ’ only purpose is to control (modulate) the other synthesiser sections, they are
commonly known as ‘modulators’.
These various synthesiser sections will now be covered in more detail.
The Oscillators And Mixer
The Oscillator section is really the heartbeat of the synthesiser. It generates an electronic
wave (which creates the vibrations when eventually fed to a loudspeaker). This waveform is
produced at a controllable musical pitch, initially determined by the note played on the keyboard
or contained in a received MIDI note message. The distinctive tone or timbre of the waveform is
actually determined by the waveform’s shape.
Many years ago, pioneers of musical synthesis discovered that just a few distinctive waveforms
contained many of the most useful harmonics for making musical sounds. The names of these
waves reflect their actual shape when viewed on an instrument called an oscilloscope, and they
are: Sine waves, Square waves, Sawtooth waves, Triangle waves and Noise. Each of Circuit
Mono Station’s Oscillator sections can generate all these waveforms, and can generate non-
traditional synth waveforms as well. (Note that Noise is actually generated independently and
mixed in with the other waveforms in the Mixer section).
Each waveform (except Noise) has a specific set of musically-related harmonics which can be
manipulated by further sections of the synthesiser.
The diagrams below show how these waveforms look on an oscilloscope, and illustrate the
relative levels of their harmonics. Remember, it is the relative levels of the various harmonics
present in a waveform which determine the tonal character of the final sound.
Sine Waves
Volume
Harmonic
1
Sine Wave
Sawtooth Wave
Volume
Volume
Harmonic
Square Wave
Volume
Harmonic
1 2 3 4 5
Volume
Harmonic
1 3 5 7
Triangle Wave
1 2 3 4 5
Harmonic
1 2 3 4 5
Noise
These possess just one harmonic. A sine waveform produces the “purest” sound because it
only has this single pitch (frequency).