Lexicon LXP-15-II Owner's Manual page 42

LXP-15 II Owner's Manual
Lexicon
Resonant Effects Singing in the shower is one way to obtain a moderate, natural resonant effect.
Startling resonances are possible with the LXP-15 II by using short delay times
with a lot of feedback. This causes a build-up of fundamental notes and
harmonies whose period (the time for one cycle) is equal to the set delay time.
These emphasized pitches are said to "resonate". The effect can be character-
ized as adding a ringing, metallic quality to the sound.
The pitch and tone of the resonance is affected by delay time, phase, amount
of feedback, and output mix. Care must be taken to keep feedback below the
point where the unit will spontaneously oscillate (runaway feedback). Use of the
Hi and Lo cut filters allows greater amount of feedback to be used.
Long Delay Effects When the delay time is equal to, or greater than, the time for a single beat of the
music, it becomes possible to play counterpoints and harmonies against
previously-performed phrases. Careful synchronization of the performance and
the delay time allows "polyphonic" sound from a single melodic line. A chart
showing conversion of tempo (in beats/minute) to Delay Time (in milliseconds)
is given at the end of this manual. The "Tempo" patch control source can be used
to automatically synchronize rhythms to a wide range of MIDI tempos.
With no feedback, only one previous phrase will be audible; if feedback is added,
each delay period will repeat more than once before it dies away. With large
amounts of feedback, the performances will pile up, one phrase over another,
until input to the delay line ceases. Using this overlay technique, it is possible to
create compositions and rhythmic beds in real-time that can be continuously
evolved by adding new notes as older ones are fading out.
Gating
Gating is an effect which does not have its origins in real-world situations (except
perhaps the silent slamming of a heavily insulated door shutting off all sound
beyond it.) Gating allows you to cut off reverberation at any point before its
natural decay time — which is in itself a dramatic effect. The LXP-15 II has a Gate
algorithm dedicated to these effects.
Pitch Shifting
Altering the pitch of the duplicate of a sound allows a variety of effects ranging
from subtle vibrato to extreme swings in pitch. Pitch shifting can be used to
create chorusing, doubling effects, or musical harmonies. The LXP-15 II has a
Pitch/Delay algorithm dedicated to these effects. Use LFO modulation or Pitch
fine for vibrato; use MIDI Note Number control of Pitch Interval for harmonizing.
4-4