8
Frequency Modulation
Coarse:
The
Coarse
knob controls the cutoff frequency of the low pass
and high pass filters and the centre frequency of the band pass and
notch filters.
•
The cutoff frequency is the point at which the filtered signal is
reduced by 3dB in amplitude.
•
The centre frequency is the midpoint between the cutoff frequencies
set by the low pass and high pass filters.
•
Turning the knob clockwise will increase the cutoff/
centre frequency.
•
Turning the knob anticlockwise will decrease the cutoff/
centre frequency.
•
If
I-ō47
is used as an oscillator, the knob controls the fundamental
frequency of the oscillator.
•
Range: ~16Hz - 16KHz.
Fine:
The
Fine
knob is used for minute control of the cutoff frequency
of the low pass and high pass filters and the centre frequency of the
band pass and notch filters. Fine tuning is relative to the value set by the
Coarse
knob.
•
Turning the knob clockwise will increase the cutoff frequency.
•
Turning the knob anticlockwise will decrease the cutoff frequency.
•
If
I-ō47
is used as an oscillator, the knob controls the fundamental
frequency of the oscillator.
FM Input:
The
FM Input
is a bipolar control voltage input for the cutoff/
centre frequency and applies exponential frequency modulation.
•
Control voltage is scaled by the
FM Attenuverter
and sums with the
level set by the
Coarse
and
Fine
knobs.
•
If
I-ō47
is self-oscillating, the
FM Input
can be used for exponential
frequency modulation of the generated sine waveform.
