Filter Modulation - E-Mu Ultraproteus Operation Manual

PRESET PROGRAMMING
84

FILTER MODULATION

The block diagram of a single channel is shown below.
Instrument
Tone
The Tone filter is a simple low-pass tone control which can be used to darken
the tone of an instrument. The Z-Plane filter is an ultra-powerful synthesizer
filter which can dramatically alter the sound of an instrument.
To understand how a filter works we need to understand what makes up a sound
wave. A sine wave is the simplest form of sound wave. Any waveform except a
sine wave can be analyzed as a mix of sine waves at specific frequencies and
amplitudes.
Any waveform can be analyzed as a mixture of sine waves.
One way to represent complex waveforms is to use a chart with frequency on
one axis and amplitude on the other. Each vertical line of the chart represents
one sine wave at a specific amplitude and frequency.
100
80
60
40
20
UltraProteus Operation Manual
Z-Plane
Filter
40 80 160 360 720 1440 2880
Frequency
DCA
Pan
...
R
L