About Wavetable Synthesis
Basics
The sound generation of the MicroWave II/XT/XTk is based on wavetable synthesis. This
type of synthesis combines analog access and digital flexibility in a simple way. Although
wavetable synthesis is a form of "sample playback" in principle, you should avoid this term
because functionality, operation and results are totally different.
The ROM area of the MicroWave II/XT/XTk currently consists of 65 wavetables, 31
locations are reserved for future ROM wavetables. The RAM area contains 32 user
wavetables, which can be manipulated over MIDI via appropriate computer software.
A wavetable is a list made up of 64 entries. Each entry represents one wave, that can be
either located in the ROM or RAM area of the MicroWave II/XT/XTk or calculated by an
algorithm after selecting the wavetable. For the purpose of using a wavetable inside a sound
program, it doesn’t matter what source the wavetable comes from.
A wavetable itself contains no wave data, but is in fact a collection of up to 64 entries
referencing up to 64 waves. Not all entries of the wavetable have to contain entries. When
one or several sequential entries contain no reference, the MicroWave II/XT/XTk calculates
the waves for these locations automatically. The algorithm producing these "imaginary"
waves uses an interpolation scheme that crossfades the "real" ones. E.g. when a wavetable
cointains entries in entry 1 and 5, the positions 2 to 4 are generated based on interpolation
between the existing waves in entry 1 and 5.
Please keep the terms "wavetable" and "wave" in mind. Don’t bring them into
confusion.
Introduction
Wavetable synthesis gives the MicroWave II/XT/XTk the unique sound character which
makes it different from all other synthesizers and samplers. The principle of wavetable
synthesis is not new, the PPG synthesizer "Wavecomputer 360", "Wave 2", "Wave 2.2" and
"Wave 2.3" and also the Waldorf MicroWave (the first one) and Waldorf Wave use this
concept. The MicroWave II/XT/XTk contains some enhancements to wavetable synthesis
which improve the sonic quality in a remarkable way.
An introduction to wavetable synthesis needs some attention because its operation
principle is different to other sound generating systems. Nevertheless you should spend a
little time in understanding the basics. You will gain more than the effort it takes.
Please note that you cannot create your own wavetables or waves with the
MicroWave II/XT/XTk itself. To do so, you need a wavetable editor, a special
computer program, that allows you to create and edit wavetables and waves. Please
ask your local dealer for such an editor software.
User’s Manual MicroWave II • MicroWave XT • XTk
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