Chapter 16 Dsp Functions; Introduction To Algorithm Programming - Kurzweil K2600 Musician's Manual

Chapter 16
DSP Functions
This chapter explains the DSP functions that can be inserted into the algorithms in the Program
Editor. As you conÞgure each algorithm, the DSP functions you select determine the type of
synthesis you apply to your sounds. Deciding which algorithm to use depends on what you
want to do; thereÕs no hard and fast rule. If you want to create a classic analog sound, for
example, youÕll choose one of the algorithms containing one or more blocks that can have Þlter
functions assigned to them. If you want real-time panning effects, choose an algorithm that
includes the PANNER function in the F3 block. Your best approach is to study the algorithm
charts in the MusicianÕs Reference, and choose the algorithm that includes the functions you want
to work with.
Before we get to the explanations of the DSP functions, weÕve included a brief discussion of a
few general concepts of sound synthesis. This should help you understand the workings of the
DSP functions. WeÕll refer to these concepts repeatedly as we go along.
Any single sound waveform is composed of numerous sine wave components, each at a
different frequency. These components are called partials. The lowest frequency is perceived by
the ear as the pitch of the sound, and is called the fundamental. The other components are called
harmonics. The relative amplitudes (volume) of each of the partials in a sound determine its
timbre, its most recognizable characteristic. When you think of the difference between the sound
of a piano and a saxophone, youÕre thinking about their different timbres. A dull sound has a
strong fundamental and weak harmonics, while a bright sound has strong harmonics.
Sound synthesis can be most simply described as the manipulation of either the amplitude or
phase of one or more of the partials constituting a sound. The K2600Õs various DSP functions
give you a variety of methods for manipulating those partials. WeÕve grouped our explanations
of the DSP functions according to the types of specialized manipulation they enable you to
perform on a given sound. The categories are as follows:
Filters
Equalization (EQ)
Pitch / Amplitude / Pan Position
Mixers
Waveforms

Introduction to Algorithm Programming

Programming the algorithms is a multi-step process. The Þrst step is selecting an algorithm.
Changing the algorithm of an existing programÕs layer is likely to alter the sound of the layer
dramatically. As a rule, then, you wonÕt want to change a layerÕs algorithm unless youÕre
building a sound from scratch. Furthermore, when you change a layerÕs algorithm, the values
for each of the DSP functions within the algorithm may be set at nonmusical values; you should
lower the K2600Õs volume slider before changing algorithms.
Deciding which algorithm to use for a new sound is primarily a process of planning a layerÕs
signal path through the sound engine. The real sound manipulation is done by the DSP
Introduction to Algorithm Programming
Added Waveforms
Nonlinear Functions
Waveforms with Nonlinear Inputs
MIxers with Nonlinear Inputs
Synchronizing (Hard Sync) Functions
DSP Functions
16-1