Moog Stage Edition User Manual page 12

LP User's Manual - The Components
Finally, the OVERLOAD parameter allows you to set the amount of signal clipping from none to soft to hard
clipping as the amount is increased. The results you get with OVERLOAD will depend on the settings of
the oscillator waves and levels, and the fi lter cutoff and the fi lter resonance settings in addition to Overload
amount. Overload is not the same distortion you'd get from a fuzz box – it must be played with to get the
best results. It can be quite subtly applied to add just a touch of 'bite', or aggressively applied to add a jaggy
edginess to the sound.
Filter Section controls:
Cutoff:
When the CUTOFF switch is selected, the analog edit control is used to adjust the fi lter cutoff frequency.
The cutoff frequency is adjustable from about 20 Hz to 16 Khz. As the edit control is rotated clockwise, the
cutoff frequency is increased, allowing more of the signal harmonics to pass through the fi lter.
Resonance:
When the RESONANCE switch is selected, the analog edit control is used to adjust the fi lter resonance.
Resonance causes feedback in the fi lter circuit, adding harmonic emphasis at the cutoff frequency. When the
Resonance control is all the way down, the lowpass fi lter acts basically as a tone control, rolling off the high
end of the signal as the Cutoff control is turned down. As Resonance is increased, the fi lter begins to form
a peak at the cutoff frequency. This emphasizes harmonics near the cutoff frequency, and can result in a 'wah-
wah' effect when resonance is set fairly high and the fi lter cutoff is varied. As the resonance is turned up the
peak increases in strength until it begins to self-oscillate – creating a sine wave with the same frequency as
the cutoff frequency.
Keyboard Control Amount (KB AMOUNT):
When the KB AMOUNT switch is selected, the analog edit control is used to adjust the amount of post-
glide keyboard voltage that is routed to the fi lter cutoff frequency. When the edit control is rotated fully
clockwise, the fi lter cutoff follows the key played on the keyboard. A higher key will cause a higher cutoff
frequency. This allows a sound to retain its brightness as it is played higher on the keyboard.
Envelope Generator Amount (EGR AMNT):
When the EGR AMNT switch is selected, the analog edit control adjusts the amount of the Filter Envelope
Generator output that affects the fi lter cutoff. The Envelope Generator Amount is bi-polar, as indicated by
the legend on the panel, so the amount is 0 when the edit control dial is at the 12 o'clock position. Rotat-
ing the control CW from that point adds a positive EG amount to the fi lter cutoff, while rotating the control
CCW from that point adds a negative amount to the fi lter cutoff.
Overload:
When the OVERLOAD switch is selected, the analog edit control adjusts the amount of pre-fi lter and post-
fi lter clipping. Overload can be used to warm up sounds and give them a distinctive tonal edge. Advancing
the edit control increases the amount of clipping from the subtle warmth of soft clipping to the 'growl' pro-
vided by the beginnings of hard clipping. When set to 100%, Overload adds a volume boost of about +6dB.
Additional CV control:
The FILTER jack on the side-panel is a CV input for external control of the fi lter cutoff parameter. The jack
accepts -5 to +5 volts, or an expression pedal like the EP-1. A voltage applied to this jack is added to the
setting of the fi lter cutoff control. A one-volt change in the control voltage will change the cutoff frequency
of the fi lter by about one octave.
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