Oscillator Extras
Oscillators
The Oscillator Extra controls are:
FM LEVEL Knob
The V-Station allows simple FM synthesis to be performed. The FM Level controls the amount
that Oscillator 3 is directly Frequency Modulated by Oscillator 2. As the FM Level is increased,
so the output of Oscillator 3 becomes more ‘metallic’ (for a description of FM synthesis, see
pages 23 and 24)
FM ENV Knob
As well as being able to frequency modulate Oscillator 3 with Oscillator 2, it is possible to
‘shape’ the output level of Oscillator 2 with a simple attack / release envelope. As this envelope
opens and closes, so more modulation is received by Oscillator 3 and, as we saw in the
Synthesis Tutorial, this allows us to dynamically control the harmonic content (and hence the
tone) of the output. The FM Level control allows you to set how much the FM Envelope affects
the FM process.
The following diagram may help you understand how the two controls interact:
Osc 2
A/R envelope
Osc 3
FM Env
FM Level
FM LEVEL sets the ‘fixed’ amount of FM; FM ENV sets the amount of ‘dynamic’ FM.
UNI DETUNE Knob
Unison Detune is used in conjunction with Uni Voices control. When using more than one
voice per note, the Unison detune amount sets how much each voice is detuned relative to
the others. Adjust the amount until the desired effect is heard.
VCO DRIFT Knob
Controls the amount of tuning drift for the oscillators. Setting a modest value, 10 for example
will cause each oscillator to slowly drift fractionally out of tune. Classic analogue synthesizers
were known to gradually go out of tune as the internal circuits heated up. This ‘instability’
actually helped to give them their own unique character!
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CONTROLS panel / Operation
