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11—Input and Track Channel Tools
162 www.rolandus.com Roland VS-2480 Owner’s Manual
The EQ Screen
What Is EQ?
A sound wave is a repeating change in air pressure that your ear perceives as a sound.
The sound wave changes over and over between its least amount of air pressure and its
greatest
very
quickly—many, many times per second. The number of times it repeats
this cycle in each second is called its “frequency.” Frequencies are measured by single
cycles (called “Hertz” or “Hz”), or by thousands of cycles (“kilohertz” or “kHz”). A low-
frequency sound wave repeats its cycle fewer times per second than a high-frequency
sound wave.
What’s important about this is that a sound wave’s frequency determines its pitch.
In fact, every sound you hear is made up of a mix of sound waves that occur so close
together in time that the ear perceives them as one single sound. Each of these sound
waves is occurring at its own frequency, of course. This means that every sound you
hear is comprised of sound waves at a variety of pitches and at different volumes, all
working together to create a single complex sound. The low-frequency sound waves
make up its bass, while the high-frequency sound waves make up its treble range.
EQ, or “equalization,” allows you to raise or lower the volume of specific sound waves
within a sound, identifying the sound waves by their frequencies. By raising or
lowering the volume of specific frequencies within a sound, you can change its
character, making it brighter or warmer, harsher or sweeter. You can lower the volume
of any frequencies you don’t like in a sound, or make other frequencies louder.
There are two basic types of devices that can manipulate a signal’s frequency content:
equalizers and filters. The VS-2480 provides both.
A device that performs equalization is called an “equalizer,” or simply “EQ” for short.
Some equalizers divide up a signal into specific frequency ranges, or “bands,” with a set
of controls assigned to each band. A low band EQ adjusts the levels of bass frequencies,
while a high band EQ operates on the treble content in a signal.
A filter reduces the level of specified frequencies within a signal by a pre-set amount.
The EQ screen filter can also boost the level of the selected frequencies under certain
circumstances, as we’ll see.
1.
4.
5.
Knob labels
2.
3.
6. 7. 8.
9.
To learn about
the CH EDIT EQ
screen’s RESET
button, see
Page 169.
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