MOTU 828es, Руководство пользователя

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M O T U A U D I O T O O L S
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useful for balancing the effect of the attack on the
transient, relative to the decay portion of the
waveform. Conversely, you can see the effect of the
threshold setting directly on the decay portion,
relative to the attack. In effect, you can see as well
as hear the results of your compression
adjustments.
To view a transient waveform in the Oscilloscope
display, turn off Waveform Recognition and use
the
Normal Trigger mode. Adjust the level high
enough to encompass the vertical amplitude of
most of the transient. If the transient pulse sweeps
across the screen, try raising the Holdoff level.
Once the transient is settled in the display and
fairly stable, you may need to adjust the horizontal
position to center it in the display. You can also
pause the display at any time and adjust the
horizontal bounds to locate a transient.
Clip detection
You can use the Oscilloscope to detect clipping in
a digital audio signal. To do so, enable all criteria
(Figure 10-12), choose
Single Sweep from the
trigger menu (Figure 10-12), set the level to 0.999
and click the trigger indicator (Figure 10-12) to
arm it (yellow). As soon as the signal clips, the
trigger indicator will turn red, and the display will
show the offending clip at the line marking time
equals zero.
Viewing timing pulses
If you have two audio signals with recognizable,
timed pulses in them, and you wish to compare
their timing with respect to each other, you can
use Split Screen or Shared view to visually
compare the timing of the two signals. You can
zoom in to the sample level for sample accurate
viewing.
Building synthesizer patches
If you are building a synth patch on a synthesizer
(or forming similar highly periodic audio
material), you can run the audio signal through
the Oscilloscope as you adjust its sound to check
in real time for undesirable (and possibly
inaudible) characteristics, which are easily seen in
the Oscilloscope display. A good example is DC
offset. If a signal develops DC offset, the apparent
vertical center of its overall waveform will drift
above or below the line marking amplitude equals
zero. Try setting Waveform Recognition to
Type I
and setting Trigger to None .
Another example is waveform polarity. If you are
combining several raw waveforms, polarity is a
critical, yet not always obvious, factor in
determining the resulting sound. You can use the
Oscilloscope to easily view and compare polarities
to see if they are inverted from one another or not.
The
Add and Subtract L - R View menu settings are
particularly useful here.
You can also use the Oscilloscope to help you
apply waveform modulation and keep it “in
bounds”. For example, you could easily see if pulse
width modulation is collapsing in on itself to
choke the sound, an effect that is readily seen in
the Oscilloscope display but not necessarily easy
to determine by ear when using multiple
modulation sources.
Guitarists can also visually observe the effects of
their pedals and processing, while playing. With
the Trigger mode set to
None and Waveform
Recognition set to Type I , the waveform will be
tracked automatically.
When applying filters and filter resonance, the
visual effect on the waveform can be invaluable in
reinforcing what you are hearing as you make
adjustments.