Specifications

188 E-MU Systems
Programming Basics
Dynamic Filters
What is a Filter? Most sounds are complex waves containing many sine waves of various
amplitudes and frequencies. A filter is a device which allows us to
remove certain components of a sound depending on its frequency. For
example, a low-pass filter lets the low frequencies pass and removes only the
high frequencies as illustrated in the following diagram.
A filter that lets only the high frequencies pass is called a high-pass filter as
illustrated in the following diagram.
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Frequency
...
Amplitude
Output of Filter
Low Pass
Filter
Cutoff Frequency
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100
40 80 160 360 720 1440 2880
Frequency
...
Amplitude
Filter Output
Initial Frequency
High Pass
Filter