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Oscillators introduction – Waldorf Nave User Manual

Page 55

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Sound Synthesis Basics

55

Nave User Manual

As soon as you play a note the envelope moves through
the wavetable positions generating different waveforms
over time.

The decay stage would move through these waves in the
opposite direction while ultimately holding a certain
wave at its sustain stage. When you release the note, the
envelope decays to zero.

Most Wavetables are created so that they start with a
hollow wave at position 0 and go through increasingly
brighter waves up to maximum position. This results in a
behaviour similar to a low pass filter so that they can be
controlled conveniently by an envelope.

If Attack is 0 and Decay set to a medium value you get a
percussive sound, if you turn up attack, you get a soft
sound start.

You can also use an LFO to modulate the wavetable
position and, depending on the selected LFO Shape, you
might get a wave scanning that goes back and forth (tri-
angle), only into one direction followed by a hard reset
to the origin (sawtooth up or down) or between only two
waves (square)

Exceeded Waves of a Wavetable

Of course you can combine envelope and keytrack mo-
dulations or add other modulation sources. All these
modulations will be added so that maybe the end or the
beginning of a wavetable could be exceeded. In this
case, the waves will be repeated cyclic.

Oscillators Introduction

The oscillator is the first building block of a synthesizer.
It delivers the signal that is transformed by all other com-
ponents of the synthesizer. In the early days of electronic
synthesis, engineers found that most real acoustic instru-
ment waveforms can be reproduced by using abstracted
electronic versions of these waveforms. They weren’t the
first who came to that conclusion, but they were the first

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0

Wave

Position

Running through the

envelope attack stage

generates this audio signal

Time