Symetrix 601, Owner'S Manual

Page: 19 / 142

2-7
Rev 2.2, 10/31/94
Converting the descriptive adjectives that people use to describe the character of a voice into
numbers that make equalizers happy is a common problem. Figure 2-2 lists some commonly
used adjectives and their corresponding frequency ranges.
2.4.9 Peaking or Shelving?
At very narrow bandwidths (small number),
peaking equalizers exhibit a phenomenon known as "ringing." This quite aptly describes the
effect of the equalizer being sharply resonant at its center frequency, which makes it
almost
oscillate.
In general, use the shelving curves to create overall color changes to the entire signal, and use
the peaking curves to modify specific regions of the signal. The peaking curves bring another
variable into play, "bandwidth" or "Q" as it is sometimes known. The bandwidth parameter
simply tells you how much of the region surrounding the center frequency will be affected.
Bandwidth and Q are inversely related; that is, a wide bandwidth (large number) corresponds
to a low Q (small number).
2.5 De-Essing
De-essing is the process of removing "S" sounds from speech or singing. The technique was
originally developed for motion picture dialogue recording when it was discovered that speech
Range Description (women)
100-250 Hz Fullness
250-400 Hz Bassiness, bigness
400-600 Hz Warmth
600-1 kHz Volume
2 kHz-4 kHz Clarity
3 kHz - 5 kHz Nasal, yell, presence
5 kHz-8 kHz Enunciation, intimacy
10 kHz up Air, mouth noises
Range Description (men)
75-200 Hz Balls, rumble, heaviness
200-300 Hz Bassiness, bigness
400-600 Hz Chesty
600-1 kHz Volume
2 kHz-4 kHz Clarity
3 kHz Nasal, yell, presence
5 kHz-8 kHz Enunciation, intimacy
10 kHz up Air, mouth noises
Figure 2-2. Descriptive adjectives used for voice ranges of men and women.
The 601s equalizer can operate in either
peaking or shelving mode. The two terms refer
to the overall shape of the equalizer's frequency
response curve. In Figure 2-3, you can see that
the peaking equalizer's effect is concentrated at
one frequency (the
center frequency), with
progressively less effect above or below the
center frequency. The shelving equalizer (which
acts more or less like the tone controls on a
home stereo) affects frequencies above or below
its characteristic frequency (depending on
whether we're talking about a low-frequency
shelving equalizer or a high-frequency shelving
equalizer).
Shelving
E.Q.
Peak/Dip
E.Q.
Rev-A
Figure 2-3. Shelving and peak/dip EQ curves.