Shure SCM410E - Manual (Page 8)

8
BASIC MIXER OPERATION
1. Adjust each channel level so that its Overload LED flickers
only during very loud speech or noise.
2. Adjust the Low-Cut and High-Frequency controls adjacent
to each Input Gain control so that the microphones sound
similar.
3. Adjust the Master level control for the required output level,
as indicated by the output peak meter. The SCM410 is now
ready for use.
NOTE: The sensitivity of the Intellimix circuitry may allow some channel gating due to static discharge or electrical distur-
bance to the power or signal lines. The unit will not be damaged; normal operation will resume after the disturbance ceases.
LIMITER
Output limiters prevent distortion during loud program peaks
without affecting normal program levels. This keeps the de-
vices connected to the SCM410 output from becoming over-
loaded. Increasing individual or Master controls on the
SCM410 increases average output and, in turn, the amount of
limiting. The limiter may be turned on via the rear panel DIP switch. The
default limiter threshold is +16 dBu. As supplied, the limiter is
defeated.
NOTE: Limiter thresholds can be changed from their factory
settings. Refer to the
INTERNAL MODIFICATIONS section.
EQUALIZER FUNCTIONS
Low Cut Filter (High-Pass)
Low-cut filters are used to reduce unwanted low frequency
sounds such as footsteps, motorized traffic, and to control
proximity effect. The SCM410 has a one-pole, low-cut (high-
pass) filter of 6 dB per octave. The low-cut filter allows all fre-
quencies above its cutoff point to pass through unchanged.
Frequencies below the cutoff are attenuated (see Figure 16).
The cutoff point is defined as the frequency where the signal
has dropped 3 dB relative to the flat, or bandpass, region. Be-
low the cutoff point, the filter exhibits increasingly more attenu-
ation as the frequency diminishes.
-10
-8
-6
-4
-2
0
+2
20 100 1,000 5,000
FREQUENCY (Hz)
FULL CCW
FULL CW
50%
ROTATION
AMPLITUDE (dB)
LOW-CUT FILTER EFFECTS
FIGURE 16
High-Frequency Shelving
The fixed-frequency equalizer produces a 6 dB boost or cut at
5 kHz and above (see Figure 17). High-frequency shelving is
extremely useful for boosting flat frequency response and
tempering sibilant vocal microphones or enhancing the sound
of off-axis lavalier microphones.
200
-10
-8
-6
-4
-2
0
+2
+4
+6
+8
+10
1,000 10,000 20,000
FREQUENCY (Hz)
FULL
CW
FULL
CCW
50%
ROTATE
AMPLITUDE (dB)
HIGH-FREQUENCY SHELVING EFFECTS
FIGURE 17