Lexicon PCM 81 - REV, User Manual

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Lexicon
3-52
PCM 81 User Guide
Voice 1-4 (or 1-2)
These parameters determine the amount of pitch shift for the left and right input
channels. In the Quad Shift algorithm, Voices 1 and 2 are left shifts and 3 and
4 are right shifts. In the 2-Voice algorithms, Voice 1 is left shift and Voice 2 is
right shift. The value is given in cents ( one cent is equal to 1/100th of a semitone
— there are 1200 cents per octave, as shown below). The full range of pitch shift
is up or down three octaves (+3600 cents). The range is adjustable in increments
of a single cent. These values can be modulated smoothly with patch sources
to create vibrato, Doppler, whammy bar and other pitch-related special effects.
Parameter Descriptions
cont'd.
All pitch shifting algorithms will produce some amount of glitches and all pitch
shift algorithms have some amount of built in delay. Single note sources shift
best. When shifting single notes, Low Pitch should be set at or below the lowest
pitch in the input material.
When shifting chords or full bandwidth material, first set the amount of shift. If you
need to minimize the delay caused by the shifter, set Low Pitch to the lowest
value and slowly increase it to the highest value that doesn’t produce unaccept-
able glitches.
The Splice parameter generally works best for most material when set to 4ms.
If the shifted audio sounds a bit harsh, you can smooth it out by raising this value.
If there is a loss of intelligibility or rhythmic accuracy in the shifted audio, try
setting Splice to a smaller value. As with most effect parameters, you should rely
on your ears to find the best settings for a given situation.
Tips for Setting
Pitch Parameters
Shift L+R
In the Stereo Shift algorithm, this parameter determines the amount of pitch shift
for both the left and right channels. This is a true stereo pitch shifter. The left and
right channels are sample synchronous to maintain stereo imaging.