GPX 1000.4 - Receiver Crunch - Free user manual and instructions

Product Type	4-Channel Amplifier
Brand	Crunch
Model	GPX 1000.4
Output Power	1000 watts max (4 x 250W RMS at 4 ohms)
Number of Channels	4
Impedance	4 ohms (2 ohms bridgeable)
Frequency Response	20 Hz - 20 kHz
Built-in Filters	Adjustable high-pass and low-pass filter (50-250 Hz)
Inputs	Stereo RCA inputs (2 pairs)
Outputs	Screw terminals (4 pairs)
Power Supply	12 V DC (vehicle battery)
Protections	Short circuit, overheating, undervoltage
Dimensions	300 x 200 x 50 mm (approx)
Weight	2.0 kg (approx)
Maintenance and Cleaning	Dust with a soft, dry cloth. Do not use chemical products.
Safety	Disconnect the battery before installation. Install the appropriate fuse on the power cable.
Spare Parts and Repairability	Spare parts are not provided. Contact Crunch customer service for any repairs.
General Information	Use: 12V vehicles, ideal for powering speakers and subwoofers.

Frequently Asked Questions - GPX 1000.4 Crunch

What is the actual power of the GPX 1000.4 amplifier?

The RMS power is 4 x 250 watts at 4 ohms, with a maximum power of 1000 watts.

Can I use this amplifier with a subwoofer?

Yes, you can bridge two channels to obtain a mono signal, which is ideal for a subwoofer.

What type of power cable should I use?

Use a 4 AWG power cable to ensure sufficient current.

How to adjust the high-pass and low-pass filters?

Use the potentiometers on the front panel: turn to set the cutoff frequency between 50 and 250 Hz.

Is the amplifier compatible with 2-ohm speakers?

Yes, it is stable at 2 ohms per channel, but bridged requires a 4-ohm load.

What to do if the amplifier overheats?

Check that the ventilation is not obstructed. Reduce the volume or install an additional fan.

How to connect multiple amplifiers?

Use an RCA splitter for the audio source and power each amplifier separately with the same battery cable.

Can I use this amplifier in a car with a 24V battery?

No, the amplifier is designed for 12V voltage. Higher voltage would damage it.

How to connect speakers?

Connect each speaker to the corresponding terminals: positive (+) and negative (-). Observe polarity.

Where can I find the complete user manual?

The complete manual is available for free download in PDF format on the website notice-facile.com.

USER MANUAL GPX 1000.4 Crunch

Please read the user's manual carefully before the installation and the first operation of the amplifier.

SPECIFICATIONS

Output Power RMS	4 x 70 W @ 4 Ohm4 x 125 W @ 2 Ohm2 x 250 W @ 4 Ohm bridged
Output Power Max.	4 x 140 W @ 4 Ohm4 x 250 W @ 2 Ohm2 x 500 W @ 4 Ohm bridged
Loudspeaker impedance (stereo)	2 – 8 Ohm
Frequency Response	5 – 50 000 Hz (-3 dB)
Total Harmonic Distortion	< 0,05 % (1 kHz)
Signal-to-Noise Ratio	> 100 dB
Input Sensitivity	150 mV – 7 V
Input Impedance	20 kOhm
Lowpass Filter (Rear-Channels)	50 – 250 Hz @ 12 dB/Octave
Highpass Filter	50 – 250 Hz @ 12 dB/Octave
Bass Boost (Rear-Channels)	Switchable 0 / 6 / 12 dB @ 45
Operating Voltage	+12 V (9 – 15 V), negative gr
Fuse Rating	2 x 20 A
Dimensions (B x H x L)	254 x 46 x 326 mm

All Specifications are subject to change

GPX1000.4

WARRANTY

This product meets the current EU minimum warranty requirements, if purchased in countries of the EU. To ensure your warranty policy keep your original receipt proofing the date of purchase. Any damage to the product as a result of misuse, abuse, accident, incorrect wiring, improper installation, alteration of date code or barcode labels, revolution, natural disaster, or any sneaky stuff because someone messed up, repair or alteration out side of our factory or authorized service centers and any thing else you have done that you should not have done is not covered. This warranty is limited to defective parts and specifically excludes any incidental or consequential damages connected therewith.

IMPORTANT NOTES PRIOR TO INSTALLATION

• This device is only suited for a 12 volt system with negative ground.
• The radiated heat while operation requires sufficient air circulation at the place of installation. It is very important that the heatsink fins do not have contact with any metal parts or any surfaces which could impair air circulation. The amplifier may not be installed in small closed location or spaces without air circulation (e.g. spare wheel recess or below the vehicle carpeting). We recommend the installation in the vehicle's trunk. Ensure sufficient protection against vibrations, dust and dirt.
• Ensure that the input and output cables are sufficiently separated from the power supply cables. Otherwise interferences may occur.
• Ensure the accessibility of the fuse and the operating elements after installation.
• The reliability and performance of the amplifier depends on the quality of installation. Preferably consult an expert to install the system, particularly if you want to install several loudspeakers.

INTERCONNECTION

POWER SUPPLY AND TURN-ON-CONNECTION

ATTENTION: Before you start with the installation, disconnect the ground connection from the vehicle's battery in order to prevent short circuits.

The power wiring which is usually installed in on-board car networks is not sufficient for a power amplifier's demands. Make sure that the power wires to GND and to the +12 V terminal has been sufficiently specified. A cable crosssection of at least 10 mm^2 must be used to connect the battery to the amplifier's terminals.

First connect the GND terminal of the amplifier to an appropriate ground connection at the chassis. To ensure a good connection, residue dirt and dust from the connection point. A loose connection may cause malfunctions or interferences noise and distortion.

Then connect the +12 V terminal of the amplifier with the battery by using an appropriate cable including an in-line fuse. This fuse should be located very close to the battery; for safety reasons not more than 30 cm away. Only insert the fuse when the installation, including the connection of the loudspeakers, has been accomplished.

Then connect the remote turn-on-wire from the headunit with the amplifier's REMOTE terminal. A cable with a cross-section of 0.5mm^2 is adequate.

AUDIO SIGNAL CABLES

When installing the audio cables between the RCA outputs of the headunit and the RCA inputs of the amplifier, the audio and power supply cables should, if possible, not be routed along the same side of the vehicle. We recommend a separated installation, e.g. routing the power cable through the cable channel on the left side and the audio cables through the cable channel on the right side or vice versa. This prevents interferences due to crosstalk into the audio signal.

LOUDSPEAKER CONNECTIONS

• In 4-channel operation (i.e. one loudspeaker on each amplifier channel), the impedance must not be lower than 2 ohms for each speaker
• In bridging mode (two amplifier outputs combined) the impedance must not be lower than 4 ohms for the bridged outputs.
• Never connect loudspeaker cables with the ground of the chassis or the +12 V supply voltage.

If the amplifier is operated with a too low impedance or incorrectly used, the entire sound system may be damaged. This means a warranty void in such cases.

SIGNAL OUTPUTS TO CONNECT ADDITIONAL AMPLIFIERS

The input signal on the IN jacks on the FRONT section (Fig. 1,8) will be routed in stereo to the output jacks OUT (Fig. 1, 7) on FRONT. Thus the OUT jack allows the connection of a additional amplifier.

OPERATING ELEMENTS

INPUT SENSITIVITY

The input sensitivity can be adjusted to any headunit. Turn the volume control of your headunit to the center medium position and then adjust the input level controls (Fig. 1,5) and (Fig. 1,9) until you have an average medium level. This setting usually provides sufficient power reserves at optimum weighted noise voltage.

VARIABLE HIGHPASS FILTER

If the amplifier is to be used for satellite loudspeakers (mid-range/tweeter loudspeakers), set the switches (Fig. 1,2) and (Fig.1, 10) to "HPF" or for bigger loudspeakers (>20 cm) to "FULL". Set the desired cross-over frequency on controller (Fig.1, 1) resp. (Fig. 1, 11). Thus to that only the frequencies above the chosen cross-over frequency will be amplified. This effectively minimizes distortions and overloads at lower frequencies. A good point to start is at 125 Hz.

VARIABLE LOWPASS FILTER

If the amplifier is used to drive a subwoofer on the REAR channels, set the switch (Fig. 1, 2) to "LPF". Set the desired cross-over frequency by using the controller (Fig. 1, 3). Thus to that only the frequencies below the chosen cross-over frequency will be amplified and the subwoofer plays more precised and efficient.

SWITCHABLE BASS-BOOST

By using the bass boost switch (Fig.1, 4) you are able to increase the bass level by 6 or 12 dB at 45 Hz.

PROTECTION CIRCUIT

The Operation-LED (POWER, fig. 1, 12) lits up, if the amplifier is in operation.

The protection LED (PROTECTION, fig. 1, 12) lits up, when the amplifier is overheated, or a short circuit occurs resp. a too low impedance load is connected to the speaker outputs. If this events, the internal built-in protection circuit shuts down the amplifier automatically. The amplifier should work again properly after you have solved the problems.

FIGURES (P. 28-30)

CONNECTIONS AND CONTROLLERS (FIG. 1)

(1) Highpass filter controller for the rear channels
(2) Selector FULL / LPF (Lowpass) / HPF (Highpass) for the rear channels
(3) Lowpass filter controller for the rear channels
(4) Selector for the stage-to-stage enhancement of the bass level for the rear channels
(5) Gain level controller for the rear channels
(6) Audio signal inputs for the rear channels
(7) Audio signal outputs to run additional amplifiers
(8) Audio signal inputs for the front channels
(9) Gain level controller for the front channels
(10) Selector FULL / HPF (Highpass) for the front channels
(11) Highpass filter controller for the front channels
(12) Protection-LED and Power-LED

POWER SUPPLY AND TURN ON CONNECTION (FIG. 2)

(1) GND terminal for the ground
(2) REMOTE terminal for the turn on connection
(3) +12 V terminal for the positive-connection of the battery
(4) Vehicle's battery
(5) In-Line Fuse (not included in the scope of delivery)
(6) Turn on wire from the headunit or the electrical antenna

4-CHANNEL OPERATION (FIG. 3)

If you want to run the amplifier with the 4 line output channels from the headunit to drive 4 loudspeakers, connect the following setup:

(1) To the headunit, line output front left
(2) To the headunit, line output front right
(3) To the headunit, line output rear left
(4) To the headunit, line output rear right
(5) Loudspeaker front left
(6) Loudspeaker front right
(7) Loudspeaker rear left
(8) Loudspeaker rear right

3-CHANNEL OPERATION (FIG. 4)

If you want to run the amplifier with the 4 line output channels from the headunit to drive a stereo loudspeaker system and a subwoofer, connect the following setup:

(1) To the headunit, line output front left
(2) To the headunit, line output front right
(3) To the headunit, line output rear left or subwoofer output
(4) To the headunit, line output rear right or subwoofer output
(5) Loudspeaker front left
(6) Loudspeaker front right
(7) Subwoofer

TROUBLESHOOTING

If you are having problems after installation follow the Troubleshooting procedures below.

Procedure 1:

Check Amplifier for proper connections.

Verify that POWER LED is on. If POWER LED is on skip to Step 3, if not continue.

1. Check in-line fuse on battery positive cable. Replace if necessary.
2. Check fuse(s) on amplifier. Replace if necessary.
3. Verify that Ground connection is connected to clean metal on the vehicle's chassis. Repair/replace if necessary.
4. Verify there is 9 to 16 Volts present at the positive battery and remote turn-on cable. Verify quality connections for both cables at amplifier, stereo, and battery/fuseholder. Repair/replace if necessary.

Procedure 2:

PROTECTION LED is on.

1. If the PROTECTION light is on, this is a sign of a possible short in the speaker connections. Check for proper speaker connections and use an ohm meter to check for possible shorts in the speaker wiring. Too low speaker impedance may also cause PROTECTION to light. This can also be a sign of driving the amplifier at very high power levels without adequate airflow around the amplifier. Shut off the system and allow amplifier to cool. Check that the vehicle charging system is maintaining proper voltage. If the previous items do not solve the problem, a fault may be in the amplifier.

Procedure 3:

Check Amplifier for audio output.

1. Verify good RCA input connections at stereo and amplifier. Check entire length of cables for kinks, splices, etc. Test RCA inputs for AC volts with stereo on. Repair/replace if necessary.

Procedure 4:

Check Amplifier for a popping noise while turning on.
1. Disconnect input signal to amplifier and turn amplifier on and off.
2. If the noise is eliminated, connect the REMOTE lead of amplifier to source unit with a delay turn-on module.

OR

1. Use a different 12 Volt source for REMOTE lead of amplifier (i.e. battery direct).
2. If the noise is eliminated, use a relay to isolate the amplifier from noisy turn-on output.

Procedure 5:

Check Amplifier if you experience excess Engine Noise.
1. Route all signal carrying wires (RCA, Speaker cables) away from power and ground wires.
OR
2. Bypass any and all electrical components between the headunit and the amplifier(s). Connect stereo directly to input of amplifier. If noise goes away the unit being bypassed is the cause of the noise.
OR
3. Remove existing ground wires for all electrical components. Reground wires to different locations. Verify that grounding location is clean, shiny metal free of paint, rust etc.
OR
4. Add secondary ground cable from negative battery terminal to the chassis metal or engine block of vehicle.
OR
5. Have alternator and battery load tested by your mechanic. Verify good working order of vehicle electrical system including distributor, spark plugs, spark plug wires, voltage regulator etc.

Dimensioni (L x A x P)

4 x 125 W @ 2 ohmios

2 x 250 W @ 4 ohmios en puente

4 x 140 W @ 4 ohmios

4 x 250 W @ 2 ohmios

2 x 500 W @ 4 ohmios en puente

2 - 8 ohmios

5 - 50 000 Hz (-3 dB)

< 0,05 % (1 kHz)

100 dB

150 mV - 7 V

20 kohmios

50 – 250 Hz @ 12 dB/octava

50 – 250 Hz @ 12 dB/octava

Cambiable 0 / 6 / 12 dB @ 45 Hz

+12 V (9 - 15 V), negativo a tierra

2 × 20 A

254 x 46 x 326 mm

4

CAR AUDIO UNLIMITED

CRUNCH

turn up your life

© 2011 Audio Design GmbH, All Rights Reserved.