QUICK START UP
If you’re like most new owners, you’re probably in a hurry to plug
your CX mixer in and use it. Here are some brief instructions to get
you going quickly. With the mixer unplugged and the unit turned off,
complete the following procedures:
1.CONNECTING AC POWER TO YOUR MIXER
• Check the rear panel to make sure the mixer has the correct AC
Line
Voltage. (120VAC or 240 VAC)
• Use only a grounded (3 prong) power outlet to prevent a shock
hazard.
This gives the quietest grounding for your mixer.
2.CONNECTING SPEAKERS (Powered Models Only)
• Use the 1/4” speaker jacks on the rear panel to connect up to four
8
Ω
speaker systems per jack (daisy chain). The speaker cables
are
to be non-shielded with a minimum size of 16 gauge.
NOTE: Do not run your speakers through microphone wire, gui-
tar
cables, or multi-conductor microphone junction boxes
or “snakes” as they are sometimes referred to. This wire is nor-
mally shielded
and of a very light gauge causing a sub-
stantial loss of power.
3.SpeakerGuard™ and the “PROTECT” LED
• The protect LED comes on along with the output relays in three
diff
erent protection modes: Shorted speaker outputs,
Speaker Impedance
below minimum rating, and when the
amplifier exceeds maximum
operating temperature.
• In event the LED comes on, turn off the amplifier and Identify and
correct any speaker cable or speaker jack shorts and make sure
the
total speaker Impedance for each output is 2 ohms or
greater. Also
make sure the fan is not blocked and
check that cool air can circu
late around the
rear of the mixer.
4.CONNECTING INPUTS TO YOUR MIXER
• For low level balanced devices such as microphones, plug into the
balanced MIC inputs using a shielded microphone cable with XLR
ends.
• For high level unbalanced devices such as instruments &
Keyboards plug into the LINE input jacks using a shielded cable
with 1/4” phone
ends. Set the GAIN switch so the level con-
trol is not over sensitive.
5.TURNING YOUR MIXER ON
• Adjust all channel and master level controls to their off positions
• Adjust all “EQ” tone controls— the channel’s Hi, Mid, and Bass
and the two master 9 Band Graphic EQ’s to their center position.
• Adjust all the Channel “PAN” controls to their center position.
• Set the power amp switch (located next to main volume) out for stereo
mode
• Turn the mixer on by the rear panel power switch and watch for
the power LED to come on. Your mixer is now ready to operate.
MIC CHANNEL FEATURES
1. LINE INPUT JACK
The Line input is a 1/4” phone jack designed for unbalanced line and
instrument level inputs. Examples of these inputs would be instru-
ments such as a guitar, a keyboard, an unbalanced mic, or a pre-amp
output. The line input can be used at the same time the mic input is
being used.
2. XLR MICROPHONE INPUT
The XLR Mic input is designed for balanced low impedance (micro-
phone) input signals. The differential balanced input amplifier
reduces the common noise picked up on the microphone cables.
The XLR connector is wired as per the industry standard, pin 1 is
ground, pin 2 is non-inverting (positive), and pin 3 is inverting (neg-
ative). Phantom power is available on every XLR input jack when the
phantom power switch in the master section is pressed. This feature
allows condenser microphones to be run directly from the mixer.
Note: When using phantom power, make sure the phantom power is
switched off before connecting or disconnecting microphones to the
mixer. It is recommended to allow 5 seconds for the phantom power
to discharge before making any microphone connections. Also, to
avoid hearing a pop, turn down the master volume when turning on
the phantom power.
3. +20DB GAIN SWITCH
The gain switch increases the input sensitivity on both the line and
mic input jacks by 20dB. After determining the input is too low for
mixing with the level control, turn down the level control, press in
the gain switch, and adjust the level again. If distortion is heard
regardless of the channel level control’s setting, disengage this
switch to eliminate over-driving of the input amplifier.
4. CHANNEL LEVEL CONTROL
The Level control adjusts the final volume of the channel before
going to the Pan control. Here is where the individual channel vol-
umes are adjusted to make up the desired mix heard at the main
outputs. A general rule to prevent distortion with in the mixer is to
always keep the MAIN master level the same or higher than the
channel LEVEL.
5. MONITOR LEVEL CONTROL
The Mon level control adjusts the volume of the channel going to the
monitor mix. Here is where the individual channel monitor volumes
are adjusted to make up the desired mix heard at the monitor out-
put. The monitor level control is pre-channel level and pre-channel
tone controls. This means it is unaffected by adjustments in channel
level and tone controls. The purpose for this is so the main mix
adjustments for tone and level can be made without disturbing the
monitor mix.
6. CHANNEL PAN CONTROL
The Pan control adjusts where the channel is heard in the stereo
field of the stereo main outputs. If it is turned to the extreme left,
then the channel will only be heard in the left main output and sim-
ilarly only in the right main output if turned to the extreme right. In
the center position the channel is heard equally in both the left and
right main outputs. A good starting point for the pan is in the cen-
ter position. Then if stereo placement is needed, a quarter turn to
the desired side from the center position gives a smooth placement
in the stereo field, or if desired a full turn to one side gives a hard
placement.
7. CHANNEL EFFECTS 1&2 LEVEL CONTROL
The EFF 1&2 control adjusts the volume of the channel going to the
internal effects Send 1 master control, and directly to the EFF SND
2 output. The effects control is post-channel level and automatical-
ly tracks the channel’s level & tone controls.
8-10. CHANNEL TONE CONTROLS
Each channel features active tone controls LO, MID, and HI. All
three function as boost (clockwise) & cut (counter-clockwise) con-
trols where the center 0 position is neutral. The LO and HI controls
are shelving type tone controls with corner frequencies at 80Hz and
11.5k Hz respectively. The MID control is a band pass type centered
around 2.2kHz. It is suggested the channel tone controls start out
in their center 0 positions. A good setting for added dynamics is to
set the LO & HI at +3, and the MID at -3.
MASTER SECTION FEATURES
11. MAIN MASTER LEVEL CONTROL
The Main control is the master volume control for all channels receiving
the signals from the channel pan controls. The Main feeds the Graphic
EQ, the main line out jacks and the internal power amplifier(s). If the
power amp switch is out, then the Main control sends a stereo mix from
all channels to both power amps
.
If the power amp switch is pushed in,
then the Main controls sends a mono mix from all channels to the left
power amp only, and the master MONITOR level sends the channel MON
to the right power amp only.
12. POWER AMP INPUT SELECTOR
The Power Amp selector selects the inputs to the two graphic EQ’s and
the power amplifiers. The out position is the normal stereo power mixer
mode. The inputs to the two EQ’s are the main left and right signals.
In the push in position the main left/right signals are combined to pro-
duce one mono signal (still controlled by the MAIN control). This mono
signal becomes the input signal to the left EQ (top EQ) and the left
power amp. Also, in the in position the output of the monitor jack and
control knob becomes the input signal for the right EQ and right power
amp.
13. MONITOR MASTER LEVEL CONTROL
The Monitor master level control is the master volume for the mon-
itor mix heard in the monitor output. This volume receives its sig-
nals from the channel monitor level controls. If the power amp
CX672, CX872 & CX1272 CONTROLS
1
2
3
6
5
4
7
8-10
CX672, CX872 & CX1272
