Inter-m CA-8320 User manual

CA-8320 Powered Mixer
Copyright 2004 Inter-M Corporation

CA-8320 Powered Mixer
Contents
Welcome ..................................................................................................................................... 3
Unpacking ............................................................................................................................... 3
Warnings .................................................................................................................................. 3
Operation................................................................................................................................. 5
Features ....................................................................................................................................... 6
Front Panel Controls.................................................................................................................... 7
Channel Section...................................................................................................................... 7
Digital Effects Section.............................................................................................................. 8
Effects Section ......................................................................................................................... 8
Tape In Section........................................................................................................................ 9
Aux In Section.......................................................................................................................... 9
Monitor Section ..................................................................................................................... 10
Main Section.......................................................................................................................... 11
Power Amp Section...............................................................................................................12
Input/Output Section ............................................................................................................14
Rear Panel Controls............................................................................................................... 16
Connections.............................................................................................................................. 17
Speaker Connection............................................................................................................. 17
External Connections............................................................................................................19
Basic Operation ........................................................................................................................ 20
Connecting Mics, Instruments and Devices ....................................................................... 20
Using The Built-In Digital Reverb........................................................................................... 20
Application-Specific Setups .................................................................................................... 21
Conference PA/Installed Sound System ............................................................................. 21
Band PA System .................................................................................................................... 23
Block Diagram .......................................................................................................................... 25
Specifications............................................................................................................................ 26
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CA-8320 Powered Mixer
Welcome
A personal welcome to you from the management and employees of Inter-M
Thank you for purchasing this fine Inter-M product. All of us here at Inter-M are dedicated
to providing you with the highest quality products and the best value.
We sincerely trust this product will provide you with years of satisfactory service, but if
anything is not to your complete satisfaction, we will endeavor to make things right.
Welcome to Inter-M, and thank you for becoming a part of our worldwide extended
family!
Unpacking
Please take a few minutes to read this brief manual and familiarize yourself with the
important information regarding product features, setup and operation.
As with most electronic devices, we strongly recommend you retain the original
packaging. In the unlikely event the product must be returned for servicing, the original
packaging (or reasonable equivalent) is required.
Warnings
Environment
Never place this product in an environment that could alter its performance or reduce its
service life. Such environments are usually characterized by high levels of heat, dust,
moisture, or vibration.
Safety
1. Read these instructions carefully.
2. Follow all instructions.
3. Keep all warnings.
4. Do not operate this apparatus near water.
5. Clean only with a damp cloth.
6. Do not block any of the ventilation openings.
7. Install in accordance with the instructions in this manual.
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CA-8320 Powered Mixer
8. Do not install near any heat sources such as radiators, heat registers, stoves, or other
devices (including amplifiers) that produce heat.
9. Do not defeat the safety purpose of the polarized or grounding type plug. A polarized
plug has two blades, with one wider than the other. A grounding type plug has two
blades and a third grounding prong. The wide blade or the third prong is provided for
your safety. If the provided plug does not fit into your outlet, consult an electrician for
replacement of the obsolete outlet.
10. Protect the power cord from being walked on or pinched, particularly at plugs,
convenience receptacles, and the point where it is attached to the apparatus.
11. Use only the attachments/accessories specified.
12. Use only with a cart, stand, tripod, bracket, or table specified, or sold with the
apparatus. When a cart is used, use caution when moving the cart/apparatus
combination to avoid overturning.
13. Unplug this apparatus during lightning storms or when unused for long periods of
time.
14. Refer all servicing to qualified service personnel. Servicing is required when the
apparatus has been damaged in any way, such as power supply cord or plug is
damaged, liquid has been spilled or objects have fallen into the apparatus, the
apparatus has been exposed to rain or moisture, does not operate normally, or
has been dropped.
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CA-8320 Powered Mixer
Operation
Make certain that speakers and input sources are properly connected before switching
on.
Keep volume levels at minimum gain and equalization set to 0dB position before
switching on.
When the AC Mains power switch is pressed, this unit starts operation with tuner display.
NOTE: The system’s operation is delayed by approximately three seconds after pressing
the AC Mains power switch. This is due to the built-in protection circuitry, designed to
protect the speakers and other system components.
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CA-8320 Powered Mixer
CA-8320
Powered Mixer
Features
Ten Inputs plus Main and Monitor Outputs
• Six Mono and two Stereo inputs, plus separate outputs for main speakers and monitor
speakers.
Dedicated Amplification for Mains and Monitors
• Two separate 200W amplifiers to power two main speakers plus another 200W
amplifier to power monitor speakers – 600W total power.
Mode Select for Bridged Mono
• Left and Right amplifiers can be bridged together to provide 400W of power.
Versatile EQ Controls
• Three-band EQ on each input channel, plus seven-band graphic EQ on main output.
Phantom Power
• Built-in +48V Phantom Power for condenser microphones.
Tape In and Aux In
• Additional inputs for connecting instruments and other line level sources.
On-Board Signal Processing
• Built-in digital effects (reverb).
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CA-8320 Powered Mixer
Front Panel Controls
Channel Section
4. Pan Pots
These knobs control the Panning (L-R) function for the associated Input Channel.
Use these to position the channel’s signal within the stereo output mix.
1. EQ Controls
These knobs provide control of
the EQ for the Input Channels.
Three bands of equalization
are provided:
Low (80Hz), ±12dB, shelving
type
Mid (2.5kHz) ±12dB, peak type
High (12kHz) ±12dB, shelving
type
2. Monitor Controls
These knobs control the level
sent to the Monitor buss. The
Monitor buss signal is sent to
the Monitor Amp jacks in the
Input/Output section, and to
the rear-panel Monitor Output
j
acks. The Monitor buss signal is
pre-fader, and is unaffected
by the channel’s Level Control
(5).
3. Effect Controls
These knobs control the level
sent to the Effect buss. The
Effect buss signal is sent to the
Input/Output section EFX
Output. The Effect output
signal is post-fader, and is
directly affected by the
channel’s Level Control (5).
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CA-8320 Powered Mixer
5. Level Control
These knobs provide control of the associated channel’s input signal level.
6. Pad Switch
These switches attenuate the input signal by –30dB. Activate this switch when
connecting a line-level source to the associated channel, or when the input
signal is distorted.
Digital Effects Section
7. Effects Select Switch
This switch selects the type of
digital reverb. Choose
between Small Hall, Large
Hall or Vocal type.
8. DSP (Digital Signal Processor)
This switch activates the
digital reverb, sending its DSP
to the Main (L/R) and Monitor
busses. The level of DSP is
controlled by the EFX/Return
controls in the Main and
Monitor sections.
Effects Section
9. Effects Out Level
This knob provides control of
the effects send level for an
external effects device as
connected to the EFX Out
jack in the Input/Output
section.
NOTE: This knob does not
control the level of the
internal digital reverb.
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CA-8320 Powered Mixer
Tape In Section
10. Tape In Control
This knob provides control of
the level of signal sent from
the Tape In jacks to the Main
L/R buss.
Aux In Section
11. Aux In Control
This knob provides control of
the signal level sent from the
Aux In jacks to the Main L/R
buss.
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CA-8320 Powered Mixer
Monitor Section
12. Monitor Graphic Equalizer
Each slider controls the cut (decreased gain) or boost (increased gain) for its
associated frequency band in the MONITOR section. The middle position
indicates flat response (no cut or boost). Moving the slider upwards increases that
frequency’s gain, while moving it down decreases the level of that frequency.
NOTE: The Monitor Graphic Equalizer affects the Monitor buss signal that is output
to the speakers, and the line level signal output to the Monitor Out jack in the
Input/Output section.
13. Monitor EFX Return Control
This knob provides control of the amount of built-in digital reverb sent to the
MONITOR buss.
14. Monitor Master Control
This knob provides control of the level of the MONITOR buss sent to both the
speakers and the MONITOR OUT jack. (Input/Output Section)
15. Monitor Output Level Display
This seven-segment LED meter indicates the amount of signal sent to the
MONITOR OUT jack. (Input/Output Section)
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CA-8320 Powered Mixer
Main Section
16. Main Graphic Equalizer
Each slider controls the cut (decreased gain) or boost (increased gain) for its
associated frequency band to the Main L/R buss. The middle position indicates
flat response (no cut or boost). Moving the slider upwards increases that
frequency’s gain, while moving it down decreases the level of that frequency.
NOTE: The Main Graphic Equalizer affects the Main L/R buss signal that is output to
the speakers, and the line level signal output to the Main Out jack in the
Input/Output section.
17. Main L/R EFX Return Control
This knob provides control of the amount of signal returned from built-in digital
reverb to the Main L/R buss.
18. Main L/R Master Control
This knob provides control of the level of the Main L/R buss sent to both the
speakers and the Main L/R OUT jack. (Input/Output Section)
19. Main L/R Output Level Display
This seven-segment LED meter indicates the amount of signal sent to the Main L/R
jack. (Input/Output Section)
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CA-8320 Powered Mixer
Power Amp Section
20. Mode Select
This switch selects the configuration (or mode) of the Main L/R Power Amplifiers.
STEREO:
The Main/LR Amplifiers send a stereo signal from the mixer section.
L+R Bridged:
The Main/LR Amplifiers are bridged (combined) to deliver a mono signal ONLY
from the Bridge jack.
21. Power Indicator
This LED indicator is lit when the AC mains to the CA-8320 is switched on.
22. Phantom Power Switch
This switch activates the phantom power supply for channels 1-6. When the
switch is switched on, +48VDC power is supplied to pins 2 and 3 of each
channel’s input connector.
Use phantom power when connecting condenser microphones, which require an
external power supply.
NOTE: It is safe to connect most modern dynamic microphones or line level
devices to the channel inputs when phantom power is activated. However, some
older ribbon microphones may be damaged by phantom power, and certain
unbalanced line level devices may malfunction or produce an audible hum
when phantom power is active.
23. Phantom Power Indicator
This LED indicator is lit when phantom power is activated.
24. Clip Indicators
These red LEDs illuminate when distortion exceeds 1% on a particular output
channel. TIP: Try reducing the input level.
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CA-8320 Powered Mixer
25. Protection Indicator
This LED indicates the state of the amplifier’s protection circuitry. When the
Protection LED is on (illuminated), the protection circuitry is active, indicating that
the unit is not operating normally. This is typically due to overheating or power
limiting. Please check the Input and Output condition of the amplifier.
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CA-8320 Powered Mixer
Input/Output Section
1. Channel Inputs 1-6
Each channel provides a high impedance (“high-Z”) input on a balanced 1/4”
tip-ring-sleeve connector for line-level devices (synths, drum machines, etc.), and
a low impedance (“low-Z”) input on a balanced 3-pin XLR jack for mic-level
sources such as condenser and dynamic microphones. Both inputs may not be
used simultaneously.
NOTE: When phantom power is switched on, +48V power is sent to the 3-pin XLR
jacks of ALL six channels (1-6). To avoid damaging high-Z devices, be sure sources
not requiring phantom power are connected only to the high-Z 1/4” jacks.
The wiring convention used in the CA8320’s inputs are as follows:
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CA-8320 Powered Mixer
2. Channel 7 & 8 Inputs
MIC INPUTS
Both channels are active balanced, eliminating input transformers while
maintaining the RF and hum rejection of transformer coupled circuits. Nominal
input level: -50dB to –20dB.
IMPORTANT: When a mic (or equivalent 150 Ωsource) is NOT connected to these
inputs, be sure the channel volume level is set to “0.”
LINE INPUTS
Channels 7 & 8 are used for connecting unbalanced line level devices such as
CD players.
NOTE: If only the L/MONO input is used, its signal is sent to both L and R busses.
3. Effects (EFX) Output Jacks
Connect this to the input of an external effects processor.
The Effects Control on each Channel Input determines the level of signal sent to
the Effects buss.
The Effects Out Control in the Effect Section determines the amount of signal
returning from the Effect Buss.
4. Foot Switch Jack
Connecting an on/off foot switch here will provide on/off control of the built-in
digital reverb. The Digital Effect switch on the front panel must be in the “ON”
position.
5. External Input Jacks
Connect line level devices such as effects processors to the Aux In jack, and
stereo devices such as CD or cassette decks to the Tape In jacks.
6. External Output Jacks
These outputs send line level signals to external devices:
Rec Out: These are unbalanced outputs on RCA jacks, for connection of an
external recording device. The output signal is pre-EQ and pre-Master L/R output
level control.
Monitor Out: This is an unbalanced 1/4" phone jack, for connection of a separate
monitor speaker.
Main Out: These are unbalanced 1/4" phone jacks, for connection of the main
output speakers. The signal is post-EQ and post- pre-Master L/R output level
control.
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CA-8320 Powered Mixer
Rear Panel Controls
1. Speaker Output Jacks
The CA-8320’s design provides up to 200W per channel to the Main L and Main R
stereo outputs, or 400W using the Bridged (mono) output jack. The separate
Monitor outputs deliver a maximum of 200W per channel.
Two 8Ωspeakers can be connected to each of the MAIN L and MAIN R jacks in a
four-speaker setup. The 400W Bridged mono output is designed to power only
one 8Ωor two 16Ωspeakers. Be careful when using the Bridged output to avoid
connecting any speakers to the Main L/R A or B jacks.
When connecting to only the A or B (not both) jacks, use a 4Ωor 8Ωspeaker.
IMPORTANT: When connecting to both A and B jacks, use an 8Ωor 16Ωspeaker
(being careful not to inadvertently connect a speaker to the BRIDGED output).
NOTE: Use the Control Panel’s Amp Select switch to select which signal is routed
to the jacks or to activate bridged mono operation.
2. Power Switch
This switch is used to switch the unit on and off. When the unit is on, the front
panel Power Indicator LED is lit.
CAUTION: Reduce the MASTER and MONITOR levels before switching the CA-8320
on or off.
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CA-8320 Powered Mixer
Connections
CAUTION: When connecting devices to your CA-8320, avoid using non-standard plugs
and cables.
Speaker Connection
The diagram below presents three approved CA-8320 speaker setups. Please take notice
of the speaker impedance (Ω) requirements of each and be careful to avoid
impedances lower than those specified.
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CA-8320 Powered Mixer
The diagrams below present the approved impedance ranges for connecting speakers
to one or both MONITOR A/B outputs. Please be careful to avoid impedances lower than
those specified.
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CA-8320 Powered Mixer
External Connections
Additional amplifiers can be connected to the MAIN L/R and MONITOR output jacks
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CA-8320 Powered Mixer
Basic Operation
Connecting Mics, Instruments and Devices
1. Switch off any powered instruments, mics, or devices before connecting to your
CA-8320. Also be sure to reduce all channel and main output levels before making
connections.
2. Connect cables to your mics, instruments, and devices before inserting the other end
firmly into the appropriate 3-pin low or 1/4” high impedance jacks on channels 1-6
Use the same procedure when connecting MIC or stereo line level devices into
channels 7 & 8.
For proper signal level, switch on the PAD switch when connecting line level devices
to channels 1-6 and please note the low and high impedance inputs cannot be used
simultaneously.
3. Switch devices on in the order they are connected to your CA-8320. Reverse the
order when switching power off.
4. Set the Main section’s Master control to the “” position.
5. To set correct input channel levels, adjust the Input Channel Level control so that the
“0” LED of the Main section’s peak level meter illuminates intermittently.
6. Rotate the Input Channel EQ knobs to change that channel’s tone.
7. Use the Main section’s Master control and Graphic EQ to adjust the overall volume
and tone.
Using The Built-In Digital Reverb
1. After setting levels and adjusting EQ, press the DSP ON switch in the DSP section.
2. Using the Effect Select switches in the DSP section, select a reverb most appropriate
for all the mics and/or instruments connected. Your three choices are:
S.HALL (small hall reverberation)
L.HALL (large hall reverberation)
VOCAL (reverb suitable for vocals)
3. Increase the Input Channel’s EFX control on the channels you want reverb, until the
desired amount of reverb is heard.
4. Using the Main/Monitor section’s EFX RTN knob, adjust the total amount of reverb
now returning from the built-in digital reverb.
NOTE: If the reverb’s sound is distorted even with the EFX RTN at minimum gain, you
will need to lower the EFX level of one or more channels.
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