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DE-1 Owner’s Manual
Reverb:
The so called Reverb effect consists of various reflection
sounds mixed together. For example, when you clap your
hands in a tunnel, you will hear the sound linger even
after you stop clapping your hands. This is the Reverb.
The sounds we normally hear in daily life have three
types of sounds mixed together, i.e., “Direct sound”, Early
Reflection sound” and “Late Reflection sound”. The
Direct sound means the sound directly reaches the ears
from the sound source. The Early Reflection sound means
the sound that comes after the Direct sound and has
rebound off the wall of the tunnel up to a few times. The
Late Reflection sound means that the sound rebounds
many times long after the Direct sound has disappeared.
Our ears normally hear the “Direct sound” - “Early
Reflection sound” - “Late Reflection sound” in that order.
Delay:
This is the effect to add a delayed sound to the original
sound. You can obtain a richer sound or completely
change the original source sound by using the Delay.
Digital Effect Functions
The DE-1 offers high quality ambient effects by employing the A. S. P. (Fostex Advanced Signal
Processing Technology), which is exclusively developed by Fostex.
With the A. S. P., you can obtain an incomparably clean and high density Hall Reverb, overwhelmingly
clear Room Reverb and wonderfully hi-fidelity Plate Reverb.
In addition to these typical Reverbs, the DE-1 provides not only various practical algorithms such as
Delay, Chorus, Flanger and Pitch Bend, but some combinations of these are also available, e.g.,
Delay+Reverb. You can choose 11 variations of the algorithm to obtain a maximum of 121 types of
different effects according to your taste and usage.
Before the practical operation, we will briefly discuss the effect functions here such as Reverb,
Delay, Chorus, Pitch and Flanger, which are integrated in the DE-1.
*H. F. A. (Harmonic Feedback Algorithm)
There is one of indispensable elements in the natural echo called “Early Reflection sound”, which is usually
sacrificed in commercial reverb products in order to reduce costs. (In practice, the Early Reflection sound
means the very first reverberated sound that bounces back from walls, floors and ceilings of concert halls).
The entire reverb sound quality depends on this Early Reflection sound and how closely it can resemble the
real echo. The H. F. A. is an algorithm that enables the effect unit to reproduce a clear and natural Early
Reflection sound by applying an ideal harmonic feedback to each delay module.
*H. D. L. P. (Hi-Density Logarithmic Processing)
The reverb sounds consist of lots of small delay elements combined in a complex way, which are produced by
many delay modules inside the effect unit. In order to obtain smooth and comfortable reverb sounds, it is very
important to efficiently organize the relationship between each delay module and minimize negative mutual
interference. The H. D. L. P. is a technology which applies efficient logarithmic processing to each delay
module, so that they can work in the most efficient way in order to eliminate harmful reverb elements and
roughness. This makes it possible to establish high density and transparent sounds.
*A. S. P. (Fostex Advanced Signal Processing Technology)
The A. S. P. is an exclusive new digital effect processing technology designed by Fostex.
This method extracts maximum efficiency from the limited DSP power. It achieves an
overwhelmingly high density Early Reflection sound and wonderfully smooth High
Dump response through the H. F. A. (Harmonic Feedback Algorithm). Also, it carries
out an elaborate reverb simulation with clear sounds through the H. D. L. P. (Hi-Density
Logarithmic Processing), which eliminates the mutual interference between the numerous
integrated delay modules and reduce the impurity and grit of the sound.
Chorus:
This makes the one original sound appear to have many
sources. The Chorus is used to widen or thicken the
original sound.
Pitch:
The Pitch basically means the frequency of the audio.
But, in the case of an effect unit, it works this way; for
instance, you can amend the vocal tone by changing the
Pitch lifting or dropping as much as an octave. Also, you
can obtain some unusual effects by mixing the shifted
Pitch sound and the original sound together.
Flanger:
The Flanger is one of applications of the Delay. This is
used to create a sound like a jet airplane ascending or
descending.