CARVIN DX Series Operation Manual Download Page 7

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2 . TH E G R A P H I C E Q U A L I Z E R S -

Each  D X mixer is provided with two nine
band graphic equalizers. Each graphic
EQ has a bypass switch and LED status
indicator located below it. The LED is
i l l u m i n a t e d   w h e n   t h e   g r a p h i c   E Q   i s
s w i t c h e d   i n t o   t h e   s i g n a l   p a t h .     T h e
graphic EQ’s are dedicated to the L/3 &
R/4 two-track outputs of the mixer.

The 9 band Graphic Equalizers in the
D X mixers provides a wide degree of
tonal flexibility. To properly use the
Graphic EQ (equalizer), set all sliders to
their center position. With the sliders at
this position, there is no effect on the
audio signal. When you raise the slider
above the center position, you boost levels in a narrow frequency band. If
you lower the slider below the center, you are subtracting levels. When
using these sliders, think of them as volume controls that can add or sub-
tract tones in narrow bands.

F r e q u e n c y: The 63 Hz slider is used for deep sub bass level adjustments,
the 125 Hz is for higher bass adjustments, the 250, 500 and 1K Hz is for
mid and higher mid tone adjustments, the 2K and 4K Hz is for mid treble
adjustments, and the 8K and 16K Hz sliders add to the very high treble
notes.

A d j u s t i n g: It is recommended that all sliders are set in their center position
before equalizing your tone. Typically low frequency feedback is in the 125
and 250 Hz range while high feedback is in the 2k and 4k Hz range.
Occasionally you may have to turn one frequency (slider) off to -12dB to
help stop feedback. But you should never turn the adjacent sliders off.
Instead, set the adjacent sliders to -6dB to form a gentle negative curve.
Likewise, if you need more deep bass, boost the 63 Hz by 10 dB and the
125Hz by 5 dB. Or, if you need more treble, boost the 8k by 6 dB and the
16k Hz by 4 dB. Note—there is not much signal at 16k so you may not hear
a big difference. If you raise or lower all sliders at the same time, the EQ
will act like a volume control because you are affecting all frequencies. Be
careful with your adjustments, because you are affecting the overall sound.

The graphic EQ’s are mainly used to “equalize” the response of the main
speakers to provide the best sound for a given room. You are able to switch
the graphics in or out of your main mix for an instantaneous evaluation of
how they are affecting your main speakers by pressing the I N / O U T s w i t c h
located just below the equalizers.

MASTER SECTION FEAT U R E S

1. THE VU METERS -

The VU meters display the relative

output signal levels of various sections of your D X mixer. A
group of four meter selector switches are located at the VU
LED array. One or more of these switches can be selected
to monitor the desired outputs. The  P F L switches in the
channels of  D X mixer override the meter selector switches,
so anytime the  P F L indicator LED is on the meters are dis-
playing the P F L l e v e l .

It is important to realize that there is no single correct reading
for the VU meters. Rather, the most important use of the
meters is to display relative signal levels. You will often
glance at the meters simply to determine if there is a signal
present at an output. It is entirely possible to have very little
or no meter movement but be producing a perfectly accept-
able signal level. In church applications there are many
occasions when the VU meters will be just barely moving,
but a perfectly acceptable signal level is being reached.
This is normal, and the VU meter is simply indicating that you
are using very little of the available output level of the con-
s o l e .

On the other hand, a rock band may produce levels that would indicate from -6
to +3 VU. Although it is perfectly normal for high level audio signal peaks to indi-
cate on the meter up into the “orange” +3dB zone, you should try to keep the
meter reading comfortably at or around “0” VU as a maximum value.

For recording applications the meters and their calibration are more important
than for sound reinforcement use. This is because you usually want to squeeze
as much signal onto tape as possible without saturating (distorting) the tape. You
normally want the meters on the mixer to be calibrated the same, and therefore to
read the same, as the meters on the recorder simply to allow you to keep your
eyes on the mixer and not have to watch the meters at the recorder all the time.

On the powered version of the D X mixer the red C L I P indicator led acts as a
power amp clip indicator, this serves as a guide to the maximum output level of
the board.

Note: if the red

C L I P

meters come on and stay on, and you are

getting no output from the internal power amps, your

D X

mixer has gone

into its protection mode.

The cause of this is usually one of two problems. The

amp may be running too hot, this can happen if there is poor ventilation through
the intake and exhaust cooling vents. Check for obstructions, and allow at least
3” of free air space around vents. Turn the mixer off and allow it a few minutes to
cool down. The other common cause for the amp to protect is if it is connected to
shorted speaker cables or an inappropriate speaker load. The internal FET amps
can safely handle speaker loads down to 4

Ω

. If your amp goes into protect mode

for a shorted cable turn the mixer off, locate and replace the bad cable and then
turn the mixer back on.

The meter calibration as shipped from the factory is +4db at the balanced outputs
equals a “0” VU indication on the LED meters. The meters can be calibrated to
your tape deck or other equipment in your studio by inserting a small flat blade
screw driver into the C A L adjustment holes and rotating the level trimmers to the
desired level.

MON

MAIN

L R

1 2

SUB

1 2

PWR

METERS

-20

-15

-12

CLIP