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Effective Use of the Envelope Parameters in the Analysis Section
The Release parameter defines the time it takes for a given synthesis frequency band to
decrease in level if the signal level of the respective analysis band decreases abruptly.
The sound is smoother when band levels decrease slowly. To achieve this smoother
character, use higher Release values in the analysis section of the interface. Don’t go too
far with this, however, as overly long release times result in a less distinct, washy sound.
Short Attack values are no problem. They may, in fact, even be desirable when a fast
reaction to incoming signals is required.
Gating Background Noises in the Analysis Signal
If the analysis signal is compressed, as recommended, the level of breath, rumble, and
background noise will rise. These unwanted signals can cause the vocoder bands to open
unintentionally. To eliminate these artifacts, you can employ a noise gate before using
compression and boosting the treble frequencies. If the analysis signal is gated
appropriately, you may be able to reduce the (Analysis) Release value.
When you are gating speech and vocals with the Logic Express Noise Gate plug-in, use
Threshold to define the level above which the gate will open, and use Hysteresis to define
a lower Threshold level, below which the gate will close. The Hysteresis value is relative
to the Threshold level.
The figure above shows a Threshold setting that is well-suited for speech compression.
Unwanted triggering by low or high frequency noise is avoided by the dedicated sidechain
filters of the Noise Gate plug-in. The Hold, Release, and Hysteresis values are suitable for
most vocal and speech signals.
Enhancing Speech Intelligibility in the EVOC 20 PolySynth
Keep these points in mind when trying to achieve the best possible speech intelligibility:
157Chapter 7 EVOC 20 PolySynth