Dave Smith Instruments POLY EVOLVER KEYBOARD - Manual (Page 25)

Level: 0…100 – Controls the volume of external audio input connected to the Left
and/or Right Audio Input jack on the back of the Poly Evolver Keyboard. The same
signal is routed to all four voices.
Note: Use the External Audio input type parameter in the Misc Parameters section
to choose the input mode.
Lowpass Filter
The analog (real analog!) lowpass filter is actually two different filters; one for the Left
channel and one for the Right channel. This allows true stereo processing of external
audio signals run through Evolver. However, for simplicity and consistency the two
filters are normally driven together in tandem, so they normally respond the same
way.
Exceptions are when using the S
PILT parameter, and when using the separate filter
cutoff and resonance modulation destinations, which allow the two filters to be
modulated independently. Note that though they are normally controlled together,
since they are analog there will always be some subtle differences between the two
filters, which gives the Poly Evolver a more natural sound.
4/2 Pole: – Selects either 2- or 4-pole operation for the filter. (The filter is in 4-pole
mode when the 4/2/P
OLE switch is lit.)
Frequency: 0…164 – Sets the base filter cutoff frequency over more than 13 octaves.
There is special smoothing on the operation of the filter knob to eliminate stepping as
you turn the knob for clean manual filter sweeps.
Resonance: 0…100 – Sets the Resonance level of the filter. At high settings the filter
will self-oscillate in 4-pole mode. If the filter does not oscillate, make sure that 4 pole
mode is selected. (The filter is in 4-pole mode when the 4/2
P OLE switch is lit.)
Env Amount: -99…+99 – Sets the amount of filter envelope to the cutoff frequency.
This can be positive or negative, allowing inverted envelope control of the filter.
Velocity: 0…100 – Amount of MIDI velocity controlling the level of the filter envelope.
Key Amount: 0…100 – Sets the amount of keyboard (MIDI note) to the filter cutoff. A
setting of 72 will step the filter one semitone for each MIDI note, 36 would be half-
semitones, and so on. Also, the MIDI note is derived using Oscillator 1 Glide, allowing
Glide tracking.
Attack: 0…110 – Sets the Attack time of the filter ADSR envelope generator
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