ESI ESI2000, Руководство по эксплуатации

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Appendix
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Flanging was originally created using two tape recorders playing identi-
cal recordings. By exactly synchronizing the two decks and then slowing
the speed of one by grasping the tape reel flanges, the flanging effect was
born.
The flanger is a stereo device consisting of two separate delay lines
controlled by a single set of controls. A Low Frequency Oscillator (LFO)
varies this initial delay setting, changing the frequency of the notches
and adding animation to the sound. LFO Rate controls the rate of
change and LFO Depth controls how much the LFO changes the delay.
The Feedback control sends some of the delayed signal through the
delay line again. When feedback is used the comb filter notches are
deepened.
Delay
Delay is an effect which can be used for doubling, reverb pre-delay, or
echoes.
Delay Time is variable from 0-635 milliseconds (mS) and controls the
time between echoes and Feedback controls how long the echoes
continue sounding. “Infinite” delay effects are possible without the risk
of runaway because of an automatic gain control in the feedback path.
Stereo Delay
Similar to delay except that the delay line outputs a stereo signal from
the mono input. The two output signals are a few milliseconds apart to
create a stereo image. The delay times is variable from 0-635 mS.
Panning Delay
A panning delay is similar to the normal delay lines except that the
echoes bounce back and forth between the two stereo speakers.
Dual Tap
These are delay lines where the signal is “tapped off” at two unevenly
spaced locations. When feedback is used, multiple complex echoes are
produced. The fraction in the name (i.e. 1/3, 1/4) refers to the distance
between the taps.
Vibrato
Basically, this a delay line modulated by an LFO, but with none of the
original signal added in. The LFO modulation creates a Doppler shift
and a resultant cyclical pitch shift. The vibrato created in this manner
sounds very different than vibrato created by frequency modulating the
sample.
Distortion
Distortion uses a technique called “soft-clipping” to create additional
harmonics in the signal. As the level increases, the top of the waveform
becomes somewhat squared. As the level increases further, it transforms
into a true square wave.