Roland M-480 Owner's Manual page 204

Appendix
Types of sound
fig.RevExp01.eps
early reflections
reverberation
direct sound
source
listener
The sound you normally hear is divided into three types: "direct sound," "early reflections," and "reverberation." The "direct
sound" is the sound that reaches the listener directly from the source. "Early reflections" are sounds that have reflected one to
several times from the walls or other surfaces of the room. "Reverberation" is sound that has reflected many times before reaching
the listener.
How sound and time are related
fig.RevExp02.eps
evel
direct sound
early reflections
reverberation
time
pre-delay
reverb time
The reflected sounds reach the listener in the following order. The pre-delay is the time from when the direct sound is heard until
the reverb arrives. The reverb time is the duration until the reverb disappears.
Tonal character of reverb
The tonal character of reverb is affected by the material of the walls and other reflective surfaces. This is because the reflectivity of
the surfaces will affect the proportion of high and low frequencies that are reflected. You can use the DFP (Damp Filter) to vary
this property of the sound. The high-frequency range or low-frequency range of the reverb will be attenuated as you decrease the
value of the HI FREQ DAMP GAIN or LO FREQ DAMP GAIN parameters, respectively.
If you want to produce soft-sounding reverb, lower the HI FREQ DAMP FREQ. If you want to produce crisp-sounding reverb, raise
the LO FREQ DAMP FREQ.
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