Adjusting The Brightness And Thickness (Filter); Filter Types - Roland GAIA Synthesizer SH-01 Owner's Manual

[PW] slider
If the [WAVE] button (p. 30) has selected
square wave), you can use this slider to specify the width
of the upper portion of the square wave (the pulse width)
as a percentage of the entire cycle.
• Moving the slider downward will narrow the pulse, making
it approach a square wave (pulse width = 50%).
• Moving the slider upward will broaden the pulse, produc-
ing a more idiosyncratic sound.
PITCH ENV (Pitch envelope)
On wind instruments such as a trumpet, the beginning of
the note (i.e., the moment at which the musician begins to
blow) may be slightly different than the pitch at which the
note stabilizes.
The pitch envelope lets you create this type of time-
varying pitch change.
[A] (Attack time) slider
This specifies the time from the moment you press the key
until the pitch reaches its highest (or lowest) point.
Moving the slider upward will lengthen this time, and
moving it downward will shorten the time.
[D] (Decay time) slider
This specifies the time from the moment the pitch reaches
its highest (or lowest) point until it returns to the pitch of
the key you pressed.
Moving the slider upward will lengthen this time, and
moving it downward will shorten the time.
[ENV DEPTH] (Envelope depth) slider
This specifies how much the pitch envelope will affect the
pitch.
• If the slider is in the upward (+) half of its range, the pitch
will initially rise and then return to the pitch of the key
you pressed. Moving the slider upward will increase the
distance by which the pitch rises.
• If the slider is in the downward (-) half of its range, the
pitch will initially fall and then return to the pitch of the
key you pressed. Moving the slider downward will increase
the distance by which the pitch falls.
Using the pitch envelope
If you want the pitch to be momentarily sharp at the
beginning of the note (e.g., as it is the instant a trumpeter
begins blowing), set [A] and [D] to very short times, and
move ENV DEPTH slightly in the "+" direction.
By setting [A] to the shortest time (the slider all the way
down), setting [D] a bit longer, and raising ENV DEPTH to
the maximum, you can simulate the downward-swooping
electronic drum sound that was popular in the 80's.
32
Adjusting the Brightness and
Thickness (FILTER)
(asymmetrical
The FILTER section contains parameters that determine the
character and distinctive features of the sound.
You can modify the tonal character by changing the filter
settings. There are various types of filters; for example a
low-pass filter (LPF) passes only the portion of the sound
that is below a specific frequency (the cutoff frequency),
and a high-pass filter (HPF) passes only the portion that is
above that frequency.
By changing the cutoff frequency of a low-pass filter,
you can make the sound brighter or darker. The cutoff
frequency can be controlled by the envelope to change
over time.
By adjusting the filter and envelope settings, you can
create sounds that have movement and expressiveness.
The filter parameters are described below.

Filter types

LPF (Low-Pass Filter)
This type of filter cuts the frequency range that is above
the cutoff frequency, making the sound more mellow.
This is the most frequently used type of filter.
Volume
Cut
region
Frequency