E-Mu Ultraproteus Operation Manual page 208

F051 4 PoleLoQ.4
A resonant low-pass filter emulation. Morphing creates the familiar filter
sweep effect.
Morph: Controls filter cutoff.
Freq. Tracking: Controls filter resonance.
Transform 2: Not used.
F052 4PoleMidQ.4
A 4-filter version of the classic 4-pole resonant filter found in most analog
synthesizers.
Morph: Controls filter cutoff.
Freq. Tracking: Controls resonance ('Q').
Transform 2: Not used.
F053 2p>4p 0
Morph: Opens up the filter making it brighter.
Freq. Tracking: This adds a small amount of resonance (Q) to the filter.
Transform 2: Changes from a 4-pole filter (-24dB/oct.) to a 2-pole filter
(-12dB/oct.).
Comments: This All Pole filter is modeled on traditional lowpass filter.
It has a soft resonance boost.
F054 LowPassPlus
Morph: Sweeps from octave peaks starting at 220Hz to inharmonic,
higher frequency peaks.
Freq. Tracking: Keyboard tracking.
Transform 2: Brightens the response.
F055 Low Past.4
Poles with fairly high 'Q' settings are grouped into the lower- to upper-
midrange. Sweeping along the Morph or Frequency Tracking axes can
produce some rather vocal-sounding effects.
Morph: Use to sweep the frequencies of the pole.
Freq. Tracking: Use to tune the filter.
Transform 2: Not used.
F056 APass.4
Simple lowpass filter with gentle rolloff above 200Hz; morphs to flat.
Morph: Gentle lowpass to flat response.
Freq. Tracking: Also moves the filter towards a flat response, allowing
you to control the depth of filtering
Transform 2: Not used.
Comments: A good choice when more subtle filtering is desired.
Z-PLANE FILTER DESCRIPTIONS
Chapter 11: Reference Section 187