Access Virus TI, Руководство пользователя

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31 FIRST STEPS
I only mentioned Sine, Sawtooth and Pulse above. However, the
Sine is only one of 64 waves available in Classic mode, and the
Pulse can change it’s “width”. The very clever knob labelled
WAVE SELECT/ PW controls both of these parameters, but not
at the same time...
WAVE SELECT/ PW
Turn SHAPE down to minimum (the display should read “Spec-
tral Wave” for a short while) and play a note on your keyboard
while turning the WAVE SELECT/ PW knob. The first two entries
in the list of WAVEs are available in many different synthesizer
models – Sine and Triangle. All the others (3 to 64) are more
complex additive waveforms. If you are interested in seeing a
graphic image of all these waves, have a look at the Oscillator
page of the VirusControl plug-in.
If the value of SHAPE is the central “Sawtooth” or above, there
is no “WAVE” in the mixture at all. In this case the
WAVE SELECT knob is free to change its function entirely – it
becomes a Pulse Width (PW) control instead...
Turn SHAPE up to maximum for a pure Pulse wave i.e. no Saw-
tooth at all, then try turning WAVE SELECT/ PW up again. The
display now reads “Oscillator 1 Pulse Width”. As the pulse
becomes narrower, the sound becomes progressively thinner –
it even disappears entirely when you reach 127.
Now play a low note on your keyboard and move the
WAVE SELECT/ PW knob fairly rapidly back and forth – this is
the typical cyclic “pulse width modulation” effect which you will
learn how to automate (using an LFO) later on.
SEMITONE
Use this knob to adjust the pitch of each oscillator over a range
of -48 to +48 semitones:
Go to ROM-A126 -START- (we are using a slightly different tem-
plate this time!) and play your keyboard. You are obviously
hearing two oscillators at the same time – and they are slightly
out of tune with each other. Use the SELECT button to choose
oscillator 2 and turn the SEMITONE knob up to +7. The steps
are automatically smoothed while you turn the knob, but the
pitch will always settle on semitones. This means you don’t use
SEMITONE for fine tuning...
DETUNE 2/3
...this is the knob you can use for fine-tuning oscillator 2 and/or
oscillator 3. Take SEMITONE back to the centre (0) and try out
different DETUNE 2/3 values while playing your keyboard.