User manual

233
Audio effects
Insert effects
Dithering
Dithering is a method for controlling the noise produced by quantization errors in
digital recordings. The theory behind this is that during low level passages, only a few
bits are used to represent the signal, which leads to quantization errors and hence
distortion.
For example, when “truncating bits”, as a result of moving from 24 to 16 bit resolution,
quantization errors are added to an otherwise immaculate recording. By adding a
special kind of noise at an extremely low level, the effect of these errors is minimized.
The added noise could be perceived as a very low-level hiss under exacting listening
conditions. However, this is hardly noticeable and much preferred to the distortion
that otherwise occurs.
When should I use dithering?
• Consider dithering when you mix down to a lower resolution, either in realtime
(during playback) or with the Export Audio Mixdown function.
A typical example is when you mix down a project to a 16-bit stereo audio file for
audio CD burning.
What is a “lower resolution” then? Well, Cubase uses 32-bit float resolution internally,
which means that all integer resolutions (16
bit, 24 bit, etc.) are lower. The negative
effects of truncation (no dithering) are most noticeable when mixing down to 8
bit,
16
bit and 20 bit format; whether to dither when mixing down to 24 bits is a matter of
taste.
Applying dithering
1. Open the Channel Settings window for the output channel by clicking its Edit
button in the MixConsole.
2. Open the effect selector for slot 7 or 8.
The two last Insert effect slots (for all channels) are post-fader, which is crucial for
a dithering plug-in. The reason is that any master gain change applied after
dithering would bring the signal back to the internal 32
bit float domain, rendering
the dithering settings useless.
3. Select the included UV22HR plug-in from the selector.
4. Make sure that the plug-in is set to dither to the correct resolution.
This would be the resolution of your audio hardware (on playback) or the desired
resolution for the mixdown file you want to create (as set in the Export Audio
Mixdown dialog, see the chapter
“Export Audio Mixdown” on page 638).
5. Use the other parameters in the control panel to set up the dithering to your liking.
Using group channels for insert effects
Like all other channels, group channels can have up to eight insert effects. This is useful
if you have several audio tracks that you want to process through the same effect (e.
g.
different vocal tracks that you want to be processed by the same compressor).
Another special use for group channels and effects is the following:
If you have a mono audio track and want to process this through a stereo insert effect
(e.
g. a stereo chorus or an auto panner device), you cannot just insert the effect as
usual. This is because the audio track is in mono – the output of the insert effect will
be in mono as well, and the stereo information from the effect will be lost.
One solution is to route a send from the mono track to a stereo FX channel track, set
the send to pre-fader mode and lower the fader completely for the mono audio track.
However, this makes mixing the track cumbersome, since you cannot use the fader.