Cobra Acoustic ACP6004 User manual

ACP6004/9004/12004 User Manual
4 Channel Power Amplifier
© Cobra International rading Ltd
®

Important Precautions & Instructions
2
Professional power amplifier ACP-series
Cobra Acoustic Professional Power Amplifiers are reliable, cost effective and designed for continuous, trouble-free
operation under rigorous use. Cobra Acoustic’s unique degree of commitment to research, quality control and testing,
results in continuous improvements to the product. The amplifier is fully protected against short circuit, over temperature
and DC output. If you need special assistance beyond the scope of this manual, please contact our technical support
department.
Warning:
Read this manual carefully bef re installing, p wering, perating, cleaning r servicing this pr duct!
Watch f r these symb ls:
Warning
To prevent fire or electric shock, do not expose this device to rain or moisture.
Before Use
• Before you start using this device, please check if there is any transportation damage. Should there be any, do not use
the device and consult your dealer first.
•Imp rtant: This device left our factory in perfect condition and well packaged. It is absolutely necessary for the user to
strictly follow the safety instructions and warnings in this user manual. Any damage caused by mishandling is not
sub ect to warranty. The dealer will not accept responsibility for any resulting defects or problems caused by
disregarding this user manual.
• Keep this booklet in a safe place for future consultation. If you sell the device, be sure to add this user manual.
• To protect the environment, please try to recycle the packing material as much as possible.
• Check the contents:
Check the carton contains: User Manual, ACP Amplifier and Power Cable.
The lighting flash with arrowhead symbol, within an equilateral triangle is intended to alert
the user to the presence of un-insulated dangerous voltage within the product’s enclosure
that may be of sufficient magnitude to constitute a risk of electric shock.
The exclamation mark within an equilateral triangle is intended to alert the user to the
presence of important operating and maintenance (servicing) instructions in the literature
accompanying the appliance.
CAU ION
RISK OF ELEC RIC
SHOCK DO NO OPEN
CAUTION: To reduce the risk of electric shock, do
not open the top cover. No user serviceable parts
inside. Refer servicing to qualified personnel.

Important Precautions & Instructions
Safety Instructions
•Cauti n: To prevent the risk of electric shock, do not remove the top cover. No user-serviceable parts inside. Refer
servicing to qualified service personnel only.
• To avoid condensation forming inside, allow the device to adapt to the surrounding temperatures when bringing it
into a warm room after transport. Condensation sometimes prevents the device from working at full performance or
may even cause damage.
• This device is for indoor use only.
• Do not place metal ob ects or spill liquid inside the device. If a foreign ob ect enters the device, immediately disconnect
the mains power.
• No naked flame sources, such as lighted candles, should be placed on the device.
• Avoid use in industrial environments.
• Keep the device away from children.
• Inexperienced persons should not operate this device.
• Maximum safe ambient temperature is 40 degrees centigrade. Do not use this device at higher ambient temperatures.
• Always unplug the device when it is not used for a long time or before you start servicing.
• Any electrical installation should be carried out by qualified personnel only, according to the regulations for electrical
and mechanical safety in your country.
• Check that the available voltage is not higher than the one stated on the rear panel of the device.
• The power cord should always be in perfect condition. Switch the device immediately off when the power cord is
squashed or damaged.
• Never let the power cord come into contact with other cables.
• Never modify the device in any way.
• When the power switch is in OFF position, this is not completely disconnected from the mains.
• This device must be earthed in order to comply with safety regulations.
• Never repair a fuse or bypass the fuse holder. Always replace a damaged fuse with a fuse of the same type and
electrical specifications.
• In the event of serious operating problems, stop using the device and contact your dealer immediately.
• Please use the original packing when the device is to be sent for service.
• Due to safety reasons it is prohibited to make unauthorized modifications to the device.
Installation
•Keep this device away from the following locations:
Locations exposed to oil splashes or steam, such as near cooking stoves, humidifiers etc.
Unstable surfaces, such as a wobbly table or slope.
Locations exposed to excessive heat, such as, near hot spot lamps, heaters or in direct sunlight.
Locations sub ect to excessive humidity or dust accumulation.
• Do not place the power cord close to a heater. It may melt, causing fire and electrical shock.
• Hold the power cord plug when disconnecting it from an AC outlet. Never pull the cord. A damaged power cord is a
potential fire and electrical shock hazard.
• Do not touch the power plug with wet hands. Doing so is a potential fire and electrical shock hazard.
• This device has ventilation holes at the front and rear to prevent the internal temperature rising too high. Do not block
them. Blocked ventilation holes are a fire hazard.
•In particular, do not:
Place the device on its side or upside down,
Place the device in any poorly ventilated location such as a bookcase or closet
Cover the device with a table cloth or place it on a carpet or bed.
• Allow enough free space around the device for normal ventilation. This should be: 5cm at the sides, 10cm behind, and
10cm above. If the airflow is not adequate, the device will heat up inside and may cause a fire.
• If several devices are to mounted in a rack, ensure that there is adequate ventilation. Extra spacing is recommended
between amplifiers and extra ventilation fans may be required in the rack.
• Take care to minimise shock and vibrations during transit.
• To relocate the device, turn the power switch off, remove the power plug from the AC outlet, and remove all
connecting cables. Damaged cables may cause fire or electrical shock. Always use good quality cable for connecting the
amplifier to other equipment. Use pre-made cables or employ a qualified engineer if you are unsure about making them
yourself.
3

4
Operation
• Use only speaker cables when connecting speakers to amplifier outputs. Using other types of cables is a fire hazard.
• Turn off all musical instruments, audio equipment, and speakers when connecting to this unit. Use the correct
connecting cables and connect as specified.
• Always lower the volume control to minimum before turning on the power to this device. A sudden blast of sound may
damage your hearing.
• Do not use this amplifier for any purpose other than driving loudspeakers.
• If you know you will not use this device for a long period of time, such as when going on vacation, remove the power
plug from the AC outlet. Leaving it connected is a potential fire hazard.
Cleaning the appliance:
• Clean by wiping with a damp cloth. Avoid getting water inside the device. Do not use volatile liquids such as benzene or
thinner which will damage the device.
• Clean the ventilation holes regularly with a vacuum cleaner. This increases the cooling capacity of the amplifier fans and
helps prevent temperature overheat.
• The amplifier must be kept clean at all times. Disconnect from the mains power supply before performing any cleaning
operation. Wipe the exterior of the amplifier with a damp cloth. Cleaning of internal parts such as filters and grilles
should be undertaken by a qualified service engineer.
Specification
Compliance
This unit is radio interference suppressed. This appliance meets the requirements of the current European and national
guidelines. Conformity has been established and the relevant statements and documents have been deposited by the
manufacturer.
Features:
• 4 Channels designed for permanent installations
• Unique LED display shows working mode, temperature, supply voltage, signal levels
• Compact 2U Housing (88mm high)
• Built-in Limiter
• Soft Start turn on
• Over Heat, short circuit, DC protection
• Balanced XLR Input Connections with link outs
• Speakon Output Connections
Model ACP6004 ACP9004 ACP12004
Power Output 8 Ohm 400 Watt x 4 600 Watt x 4 800 Watt x 4
Power Output 4 Ohm 600 Watt x 4 900 Watt x 4 1200 Watt x 4
Power Output Bridged 8 Ohm 800 Watt x 2 1200 Watt x 2 1600 Watt x 2
Frequency Response (+/-0.3dB) 20Hz - 20000Hz 20Hz - 20000Hz 20Hz - 20000Hz
Input Sensitivity 0.775V/1V/1.4V
Input Impedance 20k Ohm Blanced/10k Ohm Unbalanced
S/R Ratio >80dB
Damping Factor >200
Cooling Fan Cooling
Inputs Balanced XLR
Outputs Speakon
Power supply AC230V 50Hz
Dimensions 500 x 485 x 88mm 2U
Weight 24kg 26kg 27kg
Important Precautions & Instructions

Important Precautions & Instructions
5
Functions Front Panel
1. Rack Brackets: For Fixing the Amplifier in a Case 19” 2 units
2. Air Intake: Cold air enters here to keep internal components cool, keep the foam clean.
3. Pr tect LED:
-Lights briefly on power up
-When the internal temperature becomes too high
-When there is a technical fault: DC protection
4. Clip LEDs: Turn on when the amplifier is at its maximum, when distortion is detected. It will flash occasionally but should
not stay on. If the lights are staying on the level controls will need to be reduced.
5. Signal LEDs: These light up when a signal is present.
6. Gain C ntr ls: Ad ust these controls to set the amplifier output. Each channel has its own gain and you can use these to
set the maximum sound level for your system. In normal cases its best to have these set from 90-100% and control the
output level from a mixer.
7. LED Display: Unique LED display shows input info, including working mode, temperature, signal levels, power supply
voltage and fan speed.
8. Main Switch: Used to turn the amplifier on and off. After a few seconds the amplifier is ready to use.
❶❷
❸❹ ❺ ❼ ❽
❻
Functions Back Panel
9. Mains Input: When all audio cables are connected, plug in the IEC connector then connect to a suitable mains supply.
10. Speaker c nnecti ns: Use +1 and -1 when wiring the Speakon connectors. Leave +2 and -2 unconnected.
11. Operati n M de select r switch: Used to select the working mode of the amplifier, the most common mode is stereo.
See ‘how to use’ further on for more info.
12. Balanced XLR Signal Outputs: Can be used to connect to the next amplifier.
13. Balanced XLR Signal Inputs: Used to connect a signal from a mixer, these can be balanced or unbalanced.
15. Fans: This helps to keep the amplifier cool. It is temperature controlled so will not always be operating. Do not block this
fan or the one found on the side of the amplifier.
16. Circuit Breaker: Trips when there is an internal amplifier fault.
❾
❿⓫
⓬
⓭⓯
⓯⓰

Important Precautions & Instructions
6
Setting the operation mode
1. Stere m de: All 4 channels operate independently. Channel 1 input is controlled by gain control 1 and the signal is then
amplified to output channel 1. Channel 2-4 operates in the same way.
2. Parallel M de: Channel 1 input and gain control 1 is active and the signal is amplified to output 1 and 2. Channel 3 input
and gain control 3 is active and the signal is amplified to outputs 3 and 4. Input channel 2/4 and gain control 2/4 are
inactive.
3. Bridge M de: Channel 1+3 input and gain control 1+3 are active. Channel 2+4 and gain control 2+4 are inactive. The
amplifier power is doubled. The speakers can be connected using pin 1+ (for speaker +) and Pin 2+ (for speaker -) on the
Speakon terminal output 1 and 3. Speakon terminal 2 and 4 are inactive.

Important Precautions & Instructions
7
A note on speaker Impedance:
In parallel and stereo mode each output channel can have a minimum of a 4 Ohm load. In bridged mode the minimum is 8
Ohms.
Installation, Cooling and Wiring
Rack M unting: Due to the weight of the amplifier it is recommended to mount the amplifier into a rack with rear support
shelf rails, so the total weight is not totally on the front rack ears.
C ling: The ACP amplifier is right side and front cooled. Make sure these are not obstructed and the foam front is not
clogged with dust. If fitted in a flightcase or rack, use 1 unit spacing panels to create some distance between multiple amps
or the flightcase itself.
Speaker Cabling: Take this point seriously specially when using long cable runs. The load impedance can be altered when
using long cable runs. This will reduce output power and contribute to power loss through the cable by turning power into
heat. Most importantly use a good quality cable with a good copper content and use the shortest possible cable lengths.
The chart below gives some examplesand recommended maximum distances. See the connector wiring chart for further
information of wiring connectors.
Input Connections:
Always use a good quality screened cable. Make sure soldering has been done correctly, bad solder oints can cause
damaged or intermittent faults to occur. Try to always use balanced connections, if this is not possible try to keep
unbalanced cables as short as possible. See the connector wiring chart further on when wiring connectors.
P wering Up f r the first Time
1. Turn down all volumes.
2. Switch on your audio devices ie cd player, tuner tape deck, PCs.
3. Switch on your mixer.
4. switch on any processors between mixer and amplifier.
5. Switch on the amplifier.
6. Turn up slightly the audio source volume, then mixer volume, them processor volume.
7. Turn up the amplifiers volume slowly.
8. Make any ad ustments to the volume settings.
Do the reverse of this when powering down.
It is best to turn the amplifiers volumes up to max or almost maximum. Then control the output volume via the mixer.
Remember to try and avoid any distortion and do not over drive any audio equipment’s inputs. Always try and keep mixer
gains as low as possible and do not say turn the input gain on a mixer down and turn the main master output to maximum
to achieve the correct levels, as you may also be amplifying unwanted signal noise.
Connection Chart:
Cable ypes:
Cross Section AWG Ohms/Meter 2 Ohms 4 Ohms 6 Ohms 8 Ohms
0.75mm2 18 0.0224 4m 8m 12m 16m
1.5mm2 15 0.0112 8m 16m 24m 32m
2.5mm2 13 0.00672 15m 30m 45m 60m
4mm2 11 0.0042 22.5 45m 60m 90m

Important Precautions & Instructions
8
Stereo and Parallel Speaker Connection:
This shows suitable connections for parallel and stereo mode. Do not connect to pins 2+ and 2- as this may damage the
amplifier.
Bridge Connection:
This shows suitable connections for bridge mode. Connect between 2+ and 1+ on the Speakon plug.