Filter Modulation - E-Mu Vintage Keys Operation Manual

FILTER MODULATION

Vintage Keys contains two low pass filters for each of its 32 channels.
The block diagram of a single channel is shown below.
Instrument
Tone
Sample
Pitch
Start
The Tone filter is a simple tone control and can be used to brighten
or darken the tone of an instrument. The Low Pass filter is a power-
ful 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.
100
80
60
40
20
Low Pass
DCA
Filter
Fc Q
Aux. Volume
AHDSR AHDSR
40 80 160 360 720 1440 2880
Frequency
Pan
Volume
...
Chapter 4: Programming Basics
PROGRAMMING BASICS
R
L
33