|
Effects Explained
Delay and Reverb
Delay
Delay, or echo as it is often called, is a
simple effect that simply splits the signal into two or more parts and then
delays one part by a set time and then recombines it with the original. Most
delays also have a decay or feedback option which controls how many times the
delayed bit of audio is repeated. Each repeat gets progressively quieter in most
delay units. This creates an echo effect - imagine shouting in a cave and
hearing what you have said get repeated as it bounces off the internal walls.
There are three main types of delay, single delay, multi tap delay and ping pong
delay. A single delay is the most straight forward and, as it's name suggests,
involves one single echo which is repeated according to the feedback /decay
settings.
A multi tap delay is in effect multiple delays in one - each delay can have a
separate delay time (the length of time that is subsequently repeated) and in
some cases can have separate decay settings as well. This creates a highly
textured delay-scape which sounds either more natural or more radical depending
on how you set it up.
A ping-pong delay is a stereo delay effect which repeats the delayed signal
alternately in the left and right channels of a stereo output. This sounds
really good through a proper PA setup, or when you are recording - but is of
less use when using the standard, single channel guitar into amp set up. One
interesting effect to try is setting a very fast slapback (very short delay -
very low feedback or single) which will make it sound like two guitarists at
different sides of the stage - making the guitar sound loads fatter.
Controls
names of parameters may change from
manufacturer to manufacturer
Delay Time
Controls how much of the signal is captured and repeated.
Feedback
This controls how many times the delayed signal is repeated.
Tap
Some delays allow you to set the delay time by repeatedly tapping a foot switch
or button. This allows you to create in-tempo delay effects which can lead to
some very interesting layering effects such as playing counterpoint lead parts
with yourself.Reverb
Reverberation is the name given to the sound
created when a signal is reflected from internal walls and surfaces within a
room etc. It is much more complex than delay, as in its natural form it is
composed of countless individual delay times and decays, each with separate EQ
properties.
It is not really correct though, to refer to reverberation in terms of echoes,
as the delay times involved are very short indeed, and are in no way distinct
copies of the original sound.
Reverb effects are used to try and get the source signal to sound more natural,
or sometimes to make it sound like you are playing in a highly reverberant space
such as a cathedral. The sound of reverberation is generally regarded as
pleasing and is almost universally applied to modern recordings to create a
feeling of space and air.
There are a few different types reverb effects which all differ in the way they
simulate natural reverb.
The first form of reverb which is still often found on guitar amps today. Spring
reverbs involve the signal being passed through a transducer (a device - like a
guitar pickup - that converts energy from one form into another, in this case
electrical into mechanical) which then makes the spring vibrate. The vibrations
reach the other end of the spring and are converted back into electrical energy
by another transducer. However, the properties of the spring mean that some of
the vibrations are not converted into mechanical energy but bounce back down the
spring and react with the vibrations being created at the source end. This
creates a basic reverb effect, although it does not sound particularly natural,
it is a distinctive sound which adds brightness to the tone.
Another form of reverb effect, most often used in studios due to the expense and
bulk, are plate reverbs. Plate reverbs are a bit like spring reverbs in that
they involve passing the signal through a transducer to cerate mechanical
energy, but instead of transferring this energy to a spring it is transferred to
a metal plate. The reverberation is introduced when the vibrations reach the
edge of the plate. The reverberation is controlled by adjusting the dampening of
the plate and the positions of the transducers.
Most Reverbs are now digital in their design though the level of complexity and
sound quality varies greatly from basic digital multiFX units up to high quality
studio plug-ins. However, with the advancement of microprocessor technology, the
sound quality of all digital reverbs surpasses spring reverbs and can do decent
imitations of plate reverbs, as well as creating rich natural sounding reverbs.
Controls
names of parameters may change from manufacturer to manufacturer
Pre Delay
The pre delay sets the amount of time before the first reverberations are
introduced to the signal.
Reverb Time
This sets the length of time that the reverb lasts for - higher settings
simulate larger spaces.
Page 1, 2,
3, 4
|
