Filter Modulation; What Is A Filter - E-Mu Planet Phatt Operation Manual

FILTER MODULATION

Planet Phatt contains a Z-plane filter for each of its 32 channels. The
block diagram of a single channel is shown below.
Instrument
Tone
Sample
Pitch
Start
DAHDSR
The Tone filter is a simple tone control and can be used to brighten
or darken the tone of an instrument. Each of the 17 Z-plane filters is a
powerful synthesizer filter which can dramatically alter the sound of
an instrument.

WHAT IS A FILTER?

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.
One way to represent complex waveforms is to use a chart with fre-
quency on one axis and amplitude on the other. Each vertical line of
the chart represents one sine wave at a specific amplitude.
Z-Plane
Filter
Morph Q
Aux.
Volume
Velocity
40 80 160 360 720 1440 2880
Frequency
Chapter 4: Programming Basics
PROGRAMMING BASICS
DCA Pan
Volume
AHDSR
R
L
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