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186 Chapter 14 The EVOC 20 PS
Rate Knobs
These knobs determine the speed of modulation. Values to the left of the center
positions are synchronized with the sequencer’s tempo and include bar values, triplet
values and more. Values to the right of the center positions are non-synchronous, and
are displayed in Hertz (cycles per second).
Note: The ability to use synchronous bar values could be used to perform a formant
shift every four bars on a cycled one bar percussion part. Alternately, you could
perform the same formant shift on every eighth note triplet within the same part.
Either method can generate interesting results, and can lead to new ideas, or a new
lease of life on old audio material.
Unvoiced/Voiced (U/V) Detection
Please refer to “Analyzing Speech Signals”, from page 169 onwards, for an explanation
of the U/V Detection principle.
Speech intelligibility is highly dependent on high frequency content, as human hearing
is reliant on these high frequencies to determine syllables within words. Bear this fact
in mind when using the EVOC 20 PS, and take care with filter frequency settings in the
Synthesis and Formant Filter sections.
To aid intelligibility, it may be worthwhile using equalization to boost particular
frequencies in the mid to high frequency range, before processing the signal with the
EVOC 20 PS. Please see the “Tips for Better Speech Intelligibility” on page 169 for
further information.
Sensitivity
This parameter determines how responsive U/V detection is. By turning this knob to
the right, more of the individual unvoiced portions of the input signal are recognized.