Lexicon 300, Руководство пользователя

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4-7
The Algorithms and their Parameters
SIZE sets the rate of buildup of diffusion after the initial period (which is controlled
by DIFF). It also acts as a master control for RTIM and SPRD. The SIZE control
changes a reverb sound from very large to very small. Generally, you should set
the SIZE control to approximate the size of the acoustic space you are trying to
create, before adjusting anything else. The size in meters is roughly equal to the
longest dimension of the space. Moving SIZE while a signal is present may
cause audible transients on critical material.
The apparent size of the space created is actually a combination of the settings
of the SIZE, SHAP, and SPRD controls. Small acoustic spaces are character-
ized by a rapid buildup of diffusion. However, both small and large spaces
frequently have an uneven buildup of initial reverberation. This uneven buildup
is controlled by the SPRD and SHAP controls.
Random Hall and Feedback Pre-Echoes Pages
The Random Hall Pre-Echoes page and the Feedback Pre-Echoes page contain
four pre-echo taps with delay and level controls. The taps are fed directly to the
output wet signal rather than into the reverberator.
Pre-echoes can best be understood by visualizing a stage where the early
reflections are the sounds emanating from the rear and side stage walls directly
after the sound from the stage. Usually the rear stage wall reflection is earlier and
louder than those from the two side walls. The pre-echoes are actually clusters
of echoes, with the density of the cluster set by DIFF.
The pre-echo delay parameters change the perceived locations of reflecting
surfaces surrounding the source. Level adjusts the loudness of the reflection.
For each of the Lvl (Pre-echo level) parameters, there is a corresponding Dly
parameter. Each of these sets the delay time in ms for one of the pre-echoes.
These are not affected by PDLY, so pre-echoes can be placed to occur before
the reverberation starts.
The Dly pre-echo delay parameters have a resolution of 2 milliseconds.
The Lvl pre-echo level parameters have sixteen steps, calibrated in decibels.
The Fbk feedback parameters (for Delays 3 and 4 only) are adjustable in 6%
increments from -93% to +93%.
Pre-Echo 1, one second maximum to left channel.
Pre-Echo 2, one second maximum to right channel.
Pre-Echo 3, 2.8 seconds maximum to left channel, with feedback.
Pre-Echo 4, 2.8 seconds maximum to right channel, with feedback.
SIZE
DLY1, LVL1
DLY2, LVL2
DLY3, LVL3, FBKk3
DLY4, LVL4, FBK4