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dBcomp4 / dBcomp5 Owner's Manual

Keith Harris

Rockville dBcomp4 and dBcomp5

Class D 1-Ohm Monoblock Competition Amplifiers

 

Important Safety Instructions

A standard electrical safety warning label enclosed in a rounded rectangular border: Left Icon: A black triangle containing a white lightning bolt symbol indicating high-voltage electrical hazard. Center Text Box: A central box with a black top banner reading "CAUTION" in white uppercase text. The white lower box reads "RISK OF ELECTRIC SHOCK. DO NOT OPEN" in black uppercase text. Right Icon: A black triangle containing a white exclamation point symbol indicating a general safety hazard alert.

WARNING: BE AWARE! Use of this amplifier at extreme high volumes for extended periods of time may cause hearing loss and or hearing damage. During periods of prolonged high volume levels it is recommended that you use ear safety devices. Your ability to hear necessary traffic sounds will be impaired. While driving always keep your sound volume at reasonable levels. We at Rockville want you listening for many years to come.

  • When installing the amplifier, secure it tightly. An unmounted amplifier in your car can cause serious injury to passengers and damage to your vehicle if it is set in motion by an abrupt driving maneuver or short stop.

  • To reduce risk of electric shock, never open the unit. There are no user serviceable parts. Refer service to the Rockville service center.

  • Do not expose this unit to any kind of moisture.

  • Please ensure that the unit is situated in a properly ventilated area.

 

Installation 

Installation Basics

  • Before you begin your installation, disconnect the NEGATIVE(-) terminal from your vehicle's battery. This safety precaution will avoid possible short circuits while wiring your amplifier. 
  • Rockville amplifiers operate on 12-volt negative ground systems only. 
  • It is recommended that you lay out your sound system design on paper first. This will help you during the installation so that you have a wiring flowchart and do not miss-wire any of your components.

Mounting the Amplifier

The dBcomp Series amplifiers feature four mounting tabs located at the amplifiers four corners.  (refer to the illustration below).

  • Mounting Instructions:
    1. Choose a convenient mounting location with unobstructed airflow.
      ⚠️ Never install an amplifier in the engine compartment or on the firewall. 
    2. Lay down the amplifier and mark the location of the mounting holes. It can be installed either horizontally or vertically. 
    3. Remove the amplifier and drill pilot holes for the screws. Be sure to watch for your gas tank, gas lines, and electrical lines. Do not drill or mount any screws where they might penetrate the gas tank. 
    4. Place the amplifier and secure it to the mounting surface using the supplied screws. Please be sure to leave breathing room around the amplifier heat sink so that it can efficiently dissipate the heat it produces.

  • As connections can work loose due to vehicle vibrations during normal operation, we recommend periodically tightening all power and ground connections.

  • Do not overtighten the screws.

An illustration showing mono amplifier mounting screw placement diagram: Amplifier body showing four corner mounting tab holes aligned with mounting screws

Wiring

  1. Make sure to disconnect the NEGATIVE (-) terminal from your car's battery.

  2. Attach a 0-gauge or heavier wire to the amplifier screw terminal marked GND. The connection should be as close to the amp as possible (20 feet or less). Connect the wire to any part of the car's metal chassis. Make sure that there is no paint or other insulator blocking a good ground connection. When installing multiple amplifiers, mount them in close proximity so that they can all share the same ground point.

  3. Connect the remote terminal to the head unit's remote output using an 18-gauge or heavier wire. This connection is responsible for turning the amplifier on and off with the rest of the system. If there is no dedicated remote output, make this connection to the power antenna lead. Should your head unit not have any turn-on leads, you can wire the remote terminal to an accessory lead, which turns the amplifier on with your car's ignition.

  4. Use a 0-gauge or heavier wire to connect the screw terminal marked +12V to the battery's POSITIVE (+) terminal. In order to protect the battery and electrical systems of your car, add an in-line fuse holder within 18" of the battery. This in-line fuse offers protection against damage from short circuits. The power wire should terminate in a large ring terminal connected directly to the POSITIVE (+) terminal. An optional second fuse can be installed closer to the amplifier for additional protection to the amplifier itself. If installing multiple amplifiers, install a distribution block near their location and, using a 0-gauge wire, connect the block to the in-line holder that is connected to the battery.

  5. Insert fuse(s) into the in-line fuse holder(s) and check that all connections are properly secured.

  6. Before powering up the system, set all the amplifier's level controls to minimum, the crossover/setting switches to the desired position, and the head unit's volume to 75-85%.

  7. Reconnect the car's battery's negative terminal.

An illustration showing amplifier power wiring diagram: Wiring layout showing +12V battery power with inline fuse, remote turn-on lead connected to head unit or vehicle accessory power, and ground wire connected to negative battery terminal

Grounding

We have received amplifiers back to our service department with melted power/ground terminals caused by a bad ground connection. When there is a lack of good ground, heat builds up at the contact screws of the amplifier terminal. Over time the heat generated will begin to melt the terminal. It is a good practice to feel the power and ground wires near the amplifier after using the amp for a while. If the wires feel hot to the touch, you probably have a bad or loose connection. If after adjusting your connections the wires still feel hot, you should upgrade to the next heaviest gauge wire. As connections can work loose due to vehicle vibrations, we recommend periodically tightening all power and ground connections.

Wire Terminals

For best performance be sure to strip your wire, at minimum, as per the drawing below.

 

Settings

Adjusting the System

  • Use a small flathead screwdriver to turn the controls on the amp. 
    ⚠️ Do not apply any pressure while turning as this might break the control unit.

  • Setting Input Levels:

    1. Once the system is operational, set all crossover points to the approximate settings within the frequency response range of your speakers or subwoofers (check manufacturer's spec). In the case of a basic subwoofer system, set the Low Pass crossover at 100Hz or so. Set the Subsonic HP Filter to 25Hz and the Bass EQ to 0dB.
    2. Set the amplifier's Input Sensitivity using the control accessible on the side of the amplifier marked INPUT LEVEL (gain). Turn it counterclockwise to the MIN position. 
    3. Set your head unit's output volume to about 75%-85% of the maximum and play music.
      Please note: Any other amps connect to the head unit should be powered off. Any speakers connected directly to the head unit should be disconnected. Otherwise you may be pumping sound through speakers you do not want to.
    4. Now turn the INPUT LEVEL control on the amp clockwise until you hear clipping or distortion, then turn it counterclockwise by a notch or until the distortion is gone. The amp's input sensitivity is now set. It can be helpful to have a second person to help you set the gain.

  • Once you are satisfied with the gain control settings, use any equalizer controls to adjust the system's tonal level for personal preference. Keep in mind that after equalizing you may have to go back and reset the amplifier's level (gain) controls.

If your unit has been professionally installed, please do not change the settings set by the installer. They are the professionals! You'll want to check with them or a Rockville Tech Support rep before adjusting their settings.

Using The Built-In Low Pass Electronic Crossover

All dBcomp Series amplifiers feature 24dB per octave fully adjustable crossovers with differential circuitry.

The knob marked LOW PASS will control the low pass frequencies from 50Hz - 250Hz. A frequent error made is setting the low pass frequency too low, especially when using vented subwoofer enclosures. We recommend that for most installations you set the frequency knob between 80-150Hz depending on your preference and the rest of your audio system.

Using The Subsonic High Pass Filter

Subsonic frequencies are very low and can cause damage to your subwoofers. The Subsonic High Pass Filter will allow you to attenuate any frequencies below the set limit.

Using the Phase Shift

The Phase Shift control synchronizes the phase of your subwoofer output to that of the other speakers in the vehicle. The switch can be set to 0 or 180 degrees. Set the it to 0 and listen to a track with some bass. Now set the switch to 180 degrees, listen to the same track, and see if the bass output improves or becomes worse. Set the switch to the setting that achieves the best results.

 

Bass Remote

These amplifiers include a dash-mounted bass remote (see page 12) which allows you to control the bass level from the comfort of the driver's seat. Use the included 6-pin RJ12 cable to connect one end to the RJ12 jack on the amp and the other to the RJ12 jack on the rear of the remote.

An illustration showing remote bass knob connection diagram: Remote bass knob connected via RJ11 cable to amplifier bass remote port

 

Audio Inputs

Audio Preamp Input

This amplifier features RCA preamp inputs. Run RCA cables from your sound source to the amplifier's inputs. We suggest you use high-quality, shielded RCA patch cords to help reduce and eliminate unwanted electrical noise to your system. Use good quality RCA interconnect cables. Cheaper cables usually have poor shielding that can cause interference pickup.

⚠️ Be sure to run the RCA cables on the side of the vehicle opposite to the side used to carry the power and ground leads of the amplifier.

Stereo RCA Input & Preamp Output

Input Wiring Configuration:

Connect your head unit's RCA outputs to the amplifiers Left and Right RCA input jacks. All dB series monoblock amplifiers feature RCA pre-amp line outputs for feeding of a pass-through signal to a SLAVE full-range amplifier in a multi-amp system.

An illustration showing mono amplifier RCA input and preamp output daisy-chain wiring diagram: Stereo RCA cables connected from head unit source to dBcomp4 amplifier INPUT L and R jacks, and stereo RCA cables connected from dB15 amplifier OUTPUT L and R jacks to a secondary amplifier (dB25)

 

Output Configurations

These amps are 1-ohm stable mono block amplifiers. No matter how many woofers you choose to wire up to these models, the final impedance should not fall below 1 ohm. Please see pages 16 and 17 for various speaker impedance configurations. The dual positive and negative terminals are connected in parallel inside the amplifier. Connecting two speakers, each to one set of positive and negative terminals, will result in a parallel speaker connection. If connecting only one pair of speaker wires, it is not necessary to use both sets of connections.

An illustration showing mono amplifier subwoofer speaker terminal wiring configurations: Top diagram showing two 4 ohm parallel-wired dual voice coil (DVC) subwoofers wired in parallel to amplifier speaker terminals (1 ohm load at amp). Bottom diagram showing one 2 ohm dual voice coil (DVC) subwoofer wired in parallel to amplifier speaker terminals (1 ohm load at amp).

Twin Amp Bridging

⚠️ This setup is ONLY RECOMMENDED if your vehicle has the proper batteries to provide the amplifiers with the requisite voltage. Miswiring can lead to SEVERE DAMAGE of the amplifiers or subs. Make sure to use OFC WIRE OF THE THICKEST GAUGE POSSIBLE.

The dBcomp series amplifiers can be bridged together for double the power output into a single 2-ohm or greater load. When bridging two amplifiers together, the final impedance load of the bridged amplifiers should be no lower than 2 ohms. Double the max. 1-ohm power output will occur at 2 ohms. 

Please note: You can only bridge two of the same amplifiers together. Do not bridge different models together.

  1. Input the head unit signal into the MASTER amplifier and set the Bridged Mode switch to Output Master. 

  2. Use a MONO RCA to RCA cable to send the fully processed signal from the MASTER amplifier to the SLAVE amplifier. 

  3. Set the Bridged Mode switch on the SLAVE amplifier to Input Slave.

    • Do not input any signal to the Slave amplifier's RCA inputs. 

    • All settings will be controlled by the MASTER amplifier including input gain levels. 

    • There is no need to gain-match the two amplifiers, it will occur automatically. 

  4. The remote dash bass control should be plugged into the Master amplifier and it will control both amplifiers. 
  5. MASTER amplifier's positive (+) speaker terminal should be wired to the positive terminal of the subwoofer. 
  6. SLAVE amplifier's positive (+) speaker terminal should be wired to the negative terminal of the subwoofer. 
  7. Connect a heavy gauge wire (0-Gauge) between the negative (-) terminal of the MASTER amplifier and the negative (-) terminal of the SLAVE amplifier.
An illustration showing dual mono amplifier master/slave RCA link wiring configuration: Stereo RCA cables connected from source to MASTER INPUT L and R jacks, remote subwoofer level control connected to MASTER,. Switch set to OUTPUT MASTER on MASTER. SLAVE switch set to INPUT SLAVE, and a mono RCA link cable connecting the two amplifiers

Important note: Connect the two speaker negatives together with a 4-gauge wire strap. If this strap is not installed, the amplifiers could be damaged!

An illustration showing dual mono amplifier strapped speaker wiring configuration: One 2 ohm SVC subwoofer connected with positive lead to MASTER amplifier positive terminal, negative lead to SLAVE amplifier positive terminal, and a 4-gauge jumper wire connecting MASTER and SLAVE negative terminals

Woofer Wiring Configurations

The minimum impedance load for a single dBcomp Series amp is 1 ohm. If 2 amplifiers are bridged together then the combined output of both amplifiers will be a minimum 2 ohm load. Lower impedance loads will cause overheating and may damage the amplifiers. 

SVC (Single Voice Coil) Configurations:

⚠️ Do not mix different woofers in series and/or parallel combinations, as unequal power sharing and acoustic outputs will result. In multiple woofer setups, always use the same model for each woofer.

1-Ohm SVC Woofer

ONE 1Ω SVC WOOFER = 1Ω LOAD
One 1 ohm SVC woofer (1 ohm load at amp)

TWO 1Ω SVC WOOFERS = 2Ω LOAD
Two 1 ohm SVC woofers in series (2 ohm load at amp)

 

 

 

 

 

 

 

THREE 1Ω SVC WOOFERS = 3Ω LOAD
Three 1 ohm SVC woofers in series (3 ohm load at amp)

 

FOUR 1Ω SVC WOOFERS = 1Ω LOAD
Four 1 ohm SVC woofers in series-parallel (1 ohm load at amp)

2-Ohm SVC Woofer

ONE 2Ω SVC WOOFER = 2Ω LOAD
One 2 ohm SVC woofer (2 ohm load at amp)

TWO 2Ω SVC WOOFERS = 1Ω LOAD
Two 2 ohm SVC woofers in parallel (1 ohm load at amp)

 

 

 

 

 

 

 

TWO 2Ω SVC WOOFERS = 4Ω LOAD

An illustration showing dual voice coil (DVC) subwoofer wiring configuration: Two 1 ohm DVC woofers in series-parallel (4 ohm load at amp)

 

FOUR 2Ω SVC WOOFERS = 2Ω LOAD

Four 2 ohm SVC woofers in series-parallel (2 ohm load at amp)

4-Ohm SVC Woofer

ONE 4Ω SVC WOOFER = 4Ω LOAD
One 4 ohm SVC woofer (4 ohm load at amp)

TWO 4Ω SVC WOOFERS = 2Ω LOAD
Two 4 ohm SVC woofers in parallel (2 ohm load at amp)

 

 

 

 

 

 

 

THREE 4Ω SVC WOOFERS = 1.34Ω LOAD

Two 4 ohm SVC woofers in parallel (2 ohm load at amp)

 

FOUR 4Ω SVC WOOFERS = 1Ω LOAD

Four 4 ohm SVC woofers in parallel (1 ohm load at amp)

 

FOUR 4Ω SVC WOOFERS = 4Ω LOAD

Four 4 ohm SVC woofers in series-parallel (4 ohm load at amp)

DVC (Dual Voice Coil) Configurations:

⚠️ Do not mix different woofers in series and/or parallel combinations, as unequal power sharing and acoustic outputs will result. In multiple woofer setups, always use the same model for each woofer.

1-Ohm DVC Woofer

ONE 1Ω DVC WOOFER = 2Ω LOAD (series)
One 1 ohm DVC woofer in series (2 ohm load at amp)

TWO 1Ω DVC WOOFERS = 1Ω LOAD (series/parallel)
Two 1 ohm DVC woofers in parallel (1 ohm load at amp)

 

 

 

 

 

 

 

TWO 1Ω DVC WOOFERS = 4Ω LOAD (series)

Two 1 ohm DVC woofers in series-parallel (4 ohm load at amp)

 

THREE 1Ω DVC WOOFERS = 1.5Ω LOAD (parallel/series)

Three 1 ohm DVC woofers in series-parallel (1.5 ohm load at amp)

 

FOUR 1Ω DVC WOOFERS = 2Ω LOAD (parallel/series)

Four 1 ohm DVC woofers in series-parallel (2 ohm load at amp)

2-Ohm DVC Woofer

ONE 2Ω DVC WOOFER = 1Ω LOAD (parallel)
One 2 ohm DVC woofer in parallel (1 ohm load at amp)

ONE 2Ω DVC WOOFER = 4Ω LOAD (series)
One 2 ohm DVC woofer in series (4 ohm load at amp)

 

 

 

 

 

 

 

 

TWO 2Ω DVC WOOFERS = 2Ω LOAD (series/parallel)

Two 2 ohm DVC woofers in series-parallel (2 ohm load at amp)

 

THREE 2Ω DVC WOOFERS = 1.34Ω LOAD (series/parallel)
Three 2 ohm DVC woofers in series-parallel (1.34 ohm load at amp)

 

 

THREE 2Ω DVC WOOFERS = 3Ω LOAD (parallel/series)

Three 2 ohm DVC woofers in series-parallel (3 ohm load at amp)

 

FOUR 2Ω DVC WOOFERS = 1Ω LOAD (series/parallel)

Four 2 ohm DVC woofers in series-parallel (1 ohm load at amp)

 

FOUR 2Ω DVC WOOFERS = 4Ω LOAD (parallel/series)

Four 2 ohm DVC woofers in series-parallel (4 ohm load at amp)

4-Ohm DVC Woofer

ONE 4Ω DVC WOOFER = 2Ω LOAD (parallel)
One 4 ohm DVC woofer in parallel (2 ohm load at amp)

TWO 4Ω DVC WOOFERS = 1Ω LOAD (parallel/parallel)
Two 4 ohm DVC woofers in parallel (1 ohm load at amp)

 

TWO 4Ω DVC WOOFERS = 4Ω LOAD (series/parallel)
Two 4 ohm DVC woofers in series-parallel (4 ohm load at amp)

 

THREE 4Ω DVC WOOFERS = 2.67Ω LOAD (series/parallel)
An illustration showing dual voice coil (DVC) subwoofer wiring configuration: * Three 4 ohm DVC woofers in series-parallel (2.67 ohm load at amp)

 

FOUR 4Ω DVC WOOFERS = 2Ω LOAD (series/parallel)

Four 4 ohm DVC woofers in series-parallel (2 ohm load at amp)

 

Features

Bass Equalization Circuitry

A narrow "Q" peaking equalization circuit is included in the amplifiers. The equalization system is preset at 45Hz. The equalizer control allows you to add up to 12dB of bass boost. Utilize the bass equalizer to tailor your bass response to your system's needs. Make sure your speakers can handle the extra power output! It would be foolish to add 12dB of gain to low excursion 8" and 10" subwoofers or mid ranges and tweeters. It's a sure way to blow your speakers.

Audio Output Section

The audio output sections of the dBcomp Series mono block amps feature rugged, fast-switching MOSFETS.

Power and Protection Circuitry

These amplifiers feature our unique IC-controlled protection circuitry. This sophisticated circuit constantly monitors the heat sink internal temperature and various voltages, adjusting the amp automatically and protecting it from dangerous conditions. The three LEDs located on the side of the amplifier provide indication of the amplifier status. The POWER LED will light when the amplifier is receiving proper power, ground, and remote voltages, and the IC-monitoring sequence indicates the amp is functional. In case the amplifier encounters a diagnostic condition as listed below, the PROTECT LED will light indicating a diagnostic condition. When a diagnostic condition is sensed, the amplifier will then turn into self-preservation mode and if the cause of the diagnostic condition is not corrected will eventually shut down. There are certain critical diagnostic conditions that will turn the amplifier off immediately. The third LED is the CLIP/LIMIT LED. Please refer to the LIMITER CIRCUIT section for more information.

Thermal Protection: When the amplifier reaches an unsafe operating temperature of 80 degrees Celsius, the amplifier will turn off. Once the amplifier cools down to a safe temperature, it will automatically turn on again. If you live in a hot climate, we suggest installing additional cooling fans in your trunk to exhaust the hot air that can build up in the trunk. This will help keep the ambient temperature in the trunk as low as possible so that your amps work flawlessly and without any musical interruption.

Speaker Short Circuit Protection: Should your speakers short circuit due to voice coil burn out, or should the amplifier sense an impedance too low to handle, the protection LED will light, indicating a diagnostic condition. Turn off your system, disconnect one speaker at a time, and try to determine which speaker might be faulty. Correct the condition and restart the amplifier. You must reset the amplifier by turning it OFF and then ON again by the Remote power connection after correcting a diagnostic condition. (Turn your radio off and then on again.)

Input Overload Protection: This circuit will either shut down the amplifier completely or make the amplifier spurt on and off indicating that it is in a diagnostic condition. Turn the system off and reduce the gain on the amplifier or volume from your head unit. This should result in a corrected condition.

DC Offset Protection: Should any DC voltage try to enter the amplifier via the speaker terminals it will cause the amplifier to shut down and not operate until this condition is remedied. This circuit will also protect damaging high DC voltages from reaching your speakers should your amplifier ever malfunction.

PLEASE NOTE: You must reset the amplifier by turning it OFF and then ON again after correcting a diagnostic condition (turn your radio off and then on again). If the amplifier stays in protection after a reset, it is most likely faulty.

Limiter Circuit

The dBcomp series features a built-in limiter circuit with an On/Off switch. When the circuit is turned on, it will automatically limit input signals that may cause clipping, thus preventing damage to your subs. For competition purposes, the limiter circuit can be turned off so as to allow you to "burp" your sub. The term burping refers to playing a specific frequency through your sub for 3 to 4 seconds. This allows for maximum wattage without damage to your amp or sub.

PLEASE NOTE: Clipping occurs when an amplifier is not able to generate enough voltage to reproduce the input signal. Continuous or long-term clipping can cause serious damage to your amp and subwoofers. If you are experiencing clipping, it is recommended that you adjust your gain settings and your head unit's volume levels. Refer to "Adjusting the System" in the Settings section on page 6 for detailed instructions on how to properly set your dBcomp amplifier's gain levels.

Mute Circuit

This is an anti-thump, mute and delay circuit that eliminates irritating, speaker-damaging turn-on and turn-off transients normally experienced with less expensive amplifiers.

Bass Remote

The dash-mounted bass remote allows you to control the amplifier's bass level from the comfort of the driver's seat. It features power, protect, and clipping indicator LEDs.

  • The power LED indicates the unit is receiving power and operating nominally.
  • The protect LED will light up when the amp enters protection mode. Refer to "Power and Protection Circuitry" on page 13 for detailed information.
  • The clipping LED will light up if the limiter circuit is turned on and limiting is taking place. If the circuit is off, the LED will light when clipping occurs. Please see "Limiter Circuit" section above for more information.

Battery Voltage

Rockville dBcomp Series amplifiers feature a convenient LED readout which displays the current voltage input while the amp is in use. The amp will go into protect mode when the voltage goes below 10 volts or above 16 volts.

Additional Features

  • Digital voltage display on amp
  • High-Speed MOSFET Power Supply
  • Optical Coupler Class "D" Technology
  • Fully Adjustable 24dB/Octave Crossover with Differential Circuitry
  • Low Pass Filter: 50Hz - 250Hz
  • Subsonic Filter: 15Hz - 55Hz
  • Phase Control Switch
  • Limiter With ON/OFF Switch (You can turn off the limiter if you want to burp a sub during a competition and get more power out of the amp)
  • Full IC-Controlled Protection Circuitry
  • Remote Dashboard Subwoofer Control
  • Fully Adjustable 12dB Bass Equalizer
  • Mute and Delay Soft Start System
  • RCA Preamp Line Output
  • 8 Volt Preamp Circuitry
  • Power/Protect/Clip LED Indicators on control panel
  • Power/Protect/Clip LED Indicators on Remote control

 

Specifications

dBcomp4

  • Dyno Certified RMS Power Output:
    • 1 Ohm: 3000 Watts x 1 Channel <1% THD+N at 14.4 volts
    • 2 Ohm: 2000 Watts x 1 Channel <1% THD+N at 14.4 volts
  • Minimum THD at Rated Power: <0.1%
  • Frequency Response: 15Hz - 250Hz
  • S/N Ratio: >90dB
  • Damping Factor: >150 @ 100Hz
  • Under Voltage Protection at 10V
  • Over Voltage Protection at 16V
  • 300 Amp External Fuse
  • Dimensions: (W x H x L) 9" x 2.4" x 23"

dBcomp5

  • Dyno Certified RMS Power Output:
    • 1 Ohm: 3500 Watts x 1 Channel <1% THD+N at 14.4 volts
    • 2 Ohm: 2200 Watts x 1 Channel <1% THD+N at 14.4 volts
  • Minimum THD at Rated Power: <0.1%
  • Frequency Response: 15Hz - 250Hz
  • S/N Ratio: >90dB
  • Damping Factor: >150 @ 100Hz
  • Under Voltage Protection at 10V
  • Over Voltage Protection at 16V
  • 350 Amp External Fuse
  • Dimensions: (W x H x L) 9" x 2.4" x 23.7"

 

Troubleshooting

Problem

Cause/Solution

Amp goes into protect mode

  • Short circuit protection - Caused by the power or ground wire not being fastened tightly. Disconnect the subwoofers from the amp. If the amp is still in protect mode, you now know the issue is somewhere with the power, ground, or remote wire. You should check and make sure the ground is tight. You should check the power wire terminals. Make sure the positive is going to the positive, and the negative is going to the negative. If all this is secure, you can use a multimeter and make sure you are getting 12 - 14.4 volts coming from your power wire. If this is all checking out properly, then you should check that the remote wire is properly connected to the remote wire on your receiver. If this is correct, you should also use a multimeter and make sure your remote wire is getting at least 5 to 12 volts.

  • Thermal protection - This happens when the amplifier overheats. Check that your subwoofers are compatible with your amp and that they are wired correctly.

  • Blown subwoofer - To check for a blown subwoofer, disconnect all the subwoofers from the amplifier. If the amp goes out of protect mode, then the problem is indeed a blown subwoofer. Find which subwoofer is blown and replace it.

  • Wrong subwoofer impedance - Replace the subwoofer(s) with one of the proper impedance.

  • Speaker wires touching - If the positive and negative speaker wires that run from your subwoofers to your amplifier touch each other either by the speaker terminals or by the amplifier terminals, the amp will go into protect mode. Check all subwoofer connections to ensure that the wires are not touching.

  • Reverse polarity protection - Reverse polarity means the positive and negative power wires are backward. Connect the speaker wires to the correct terminals.

  • Power wire gauge - If your power and ground wire are not thick enough, the amp will go into protect mode to protect itself from unsafe signals. Be sure to use the proper gauge wires.

  • RCA cables - RCA patch cables that are grounded out or otherwise faulty can also cause the protect light to come on. To check this, you can simply hook up a set of known good RCA cables to your head unit and amp. If that causes the light to turn off, replacing the RCA cables will fix the problem.

Amp won't power on

  • The external fuse is not properly secured to the power wire or is not making proper contact to the wire. Ensure the fuse is properly seated and making contact.

  • Your external fuse (inside the fuse holder) is blown. Replace the fuse. Never replace the supplied external fuse with one of a larger value.

  • Check the ground wire. Make sure the connection is 100% secure and tight.

  • Power wire is not connected properly to the ring terminal or it has acid corrosion on it. Check the connection to the ring terminal and use a wire brush to clean any corrosion off the ring.

  • Check the power wire. Make sure the positive is wired to the positive, and the negative is going to the negative. Make sure the power wire is secure.

  • Check the remote turn-on wire. Make sure that this wire is connected securely to the amplifier on one end, and make sure the other end is connected to the remote turn-on of the receiver. Please note, when using RCA inputs the remote turn-on wire is a required wire. The amp will not work if this is not connected.

  • Power wire is connected to the ground terminal of the amplifier. Connect the power wire to the +12V terminal of the amp.

  • Power or ground wire became loose. Check all connections and make sure they are tight.

Power but no sound

  • Check if any protection lights are on. If protection lights are on, please refer to the "Power and Protection Circuitry" section and the "Amp goes into protect mode" section.

  • Check the RCA cable that is going from the amplifier to the receiver. We recommend having a spare RCA cable to test with. Many times RCA cables go bad since they are thin cables. You can also test your RCA signal using a multimeter.

  • The next thing to check is the speaker wire that is going from the amp to the subwoofers. Make sure the speaker wire is connected to the proper terminals.

  • Check your level (gain) - on the amp and/or on your level remote. If it is on 0, then turn it up slowly.

  • Check the RCA cable that is plugged into your receiver. Make sure you plugged the amplifier into the sub pre-amp output that is red and white. In many cases we have seen customers plug the RCA into the RCA video of their receiver, which is yellow. If this is the case, just plug the RCA into the proper connections and your problem will be solved.

  • There is a setting on your receiver that can disable your RCA outputs. The setting is under subwoofer output control. On your receiver navigate to subwoofer output and find the setting, then make sure you enable front, rear, and sub preamp outputs. Sometimes the head unit will allow you only to enable front and rear, which would cause the amp to have no sound. Make sure to enable the sub output.

  • Speaker wire is not making a good contact on the sub output of the amp or on the speaker terminal. You need to make sure the speaker wire is securely tightened into the speaker terminal and the amplifier terminal.

  • A pinched or cut speaker wire that is now not running a signal. Speaker wire is very thin and can rip or tear easily. If you have spare speaker wire, then you can test this issue with new speaker wire and see if that solves your issue. You can also visually inspect your current speaker wire.

  • Make sure the positive and negative speaker wire are running to the positive and negative speaker terminal of the amp.

Amp is clipping

  • Subwoofers are too powerful for the amplifier you are using. Check the compatibility of your subwoofers. Replace incompatible subwoofers with compatible ones. 

  • If the subwoofers are wired at a lower impedance (ohms) than the amp is supposed to be playing, this can cause the amp to clip. Wire the subwoofers at the proper impedance or use the proper ones.

  • If the level (gain) setting is too high, this can cause the amp to clip. The proper way to set your level (gain) is to turn your receiver volume to 75% of the max, and then slowly turn your gain up. The second you hear any slight distortion, turn it down one notch and leave it at that setting. Amps are not meant to be played with the level (gain) up to the max. If this is the case, lower your level (gain) slowly until you hear the amplifier stop clipping.

  • A poor ground cable connection can cause your amp to clip because improper power is getting to the amp. Check your ground connection and make sure that the cable is securely tightened.

  • A very common cause of amplifier clipping is power and ground wire that is too thin of a gauge size for the amplifier. Determine the proper wire gauge necessary and replace existing wires.

  • If using multiple devices that all have a volume control (such as an equalizer or processor, receiver, and the amp), then you would need to lower one or two of those devices to stop the amp from clipping.

Distortion, background noise, crackling, or hissing in the subwoofers

  • First check to see how your wires are run. If your RCA cables and speaker wire are run alongside your power cables, they will pick up feedback. If this is the case, you will need to run the RCA cable on the other side separate from your power cable.

  • A poor ground cable connection can cause your amp to clip because improper power is getting to the amp. Check your ground connection and make sure that the cable is securely tightened.

  • Engine noise - you will know it is engine noise if every time you rev your engine the noise gets louder. You can install a ground loop isolator on the receiver's power lead to cut down on signal pollution. Most often, however, engine noise comes from a loose or intermittent ground connection. Make sure your ground connection is tight and that you are using the proper gauge cable.

  • If your gain on your amp is set to the max and your receiver has a high preamp voltage, it will cause some unwanted noise. To properly set your gain, play a CD or other music. Now put the receiver volume to 75% - 80% of the max. Then slowly turn the gain of the amp to a setting where you do not hear a loud hiss. A low hiss is acceptable, as with music playing you will never hear it. Please note the amp gain is not a volume control. It is meant to be matched to the preamp voltage of a head unit. It is important to properly set your gain when you buy a new amp.

  • Noise can be picked up due to bad RCA cables. Specially the super cheap ones. We recommend doing a test with different RCA cables. Replace the RCA cables if needed. 

  • Low-quality speaker wires will also cause noise. We recommend you buy high-quality insulated speaker wire made for vehicle applications.

Sound is too low

  • This can be caused by wiring at too high of an impedance (ohms) and the amp puts out low power, at 4 or 8 ohms for example. To resolve this, you will have to properly wire your subwoofers to the amplifier.

  • Check the gain level on the amp. You may need to turn it up.

  • Power and ground wire that are too thin of a gauge size for the amplifier may cause low sound. Determine the proper wire gauge necessary and replace existing wires.

  • Check your LPF control setting on your amplifier. If it set too low the output will sound low. Try raising the frequency and see if that helps.

  • On your receiver it is very common to have a volume level control for the preamp outputs (separate from your master volume control). To fix this, you can navigate to the audio settings, and search for subwoofer level controls, as well as front and rear preamp output controls. Crank up the level on this setting and you will be back in business.

  • Amplifier may not be powerful enough. If this is the case, we recommend upgrading to a more powerful amplifier.

Amp keeps blowing fuses

  • Main Fuse – If you determine that your main fuse is blowing, then you'll want to pay attention to when it blows. Try inserting a good, properly rated fuse with your head unit and amplifier turned off. If the fuse blows immediately, when everything is off, then you're probably dealing with some kind of short in the power cable between the main fuse and the distribution block, or between the main fuse and the amplifier if there is no distribution block in the system.

  • Distribution Block Amp Fuse - If both sides of the main fuse have power, and one side of the distribution block has power, but the other side of that fuse is dead, then you're either dealing with a shorted power wire or an internal amplifier fault. There are a few ways to determine which one is the culprit, depending on how your amp is installed and where the wires are routed.

  • Check if you can see power wire that connects the distribution block to your amp. In an ideal situation, you'll be able to see the entire length of the wire. If that isn't possible, then the next best thing is to just disconnect the power wire from your amp, make sure that the loose end isn't in contact with ground, and check whether the fuse still blows. If it does, then the problem is in the power wire, and replacing it will almost certainly fix your problem. Of course, you'll have to take care when routing the new wire so that it doesn't end up shorting out as well. If the fuse doesn't blow with the power wire disconnected from your amp, then you have an internal amplifier problem.

  • Internal Amplifier Fuse - If the fuse blows when the amp is turned up, then you likely have subwoofers that are either incompatible or that are wired at too low of an impedance. Rewire to achieve proper impedance, or replace the subwoofers with compatible ones. Check and make sure the power and ground wires did not get crossed. Also, check and make sure your speaker wires are not crossed.

Amp gets very hot

  • The main reason amps overheat is if the impedance they are running at is very low, or if the subwoofer requires more power than the amp can give it. Also if the wiring cannot give the proper current fast enough, it can cause the amp to get hot as well. Make sure the amp is running at the proper impedance, or use subwoofers that are compatible with the amp. Make sure the wiring is correct and you are using the proper wires for your system.

  • A poor ground cable connection can cause your amp to get very hot. Check your ground connection and make sure that the cable is securely tightened.

  • Check the location where your amp is mounted. Make sure it is in a spot where it will receive proper ventilation.

Amp or powered sub does not turn off when you turn off the vehicle

  • This situation happens when you connect the remote turn-on wire to a constant 12V power wire (often this is a yellow wire) instead of to the remote turn-on wire of your receiver's wire harness. Pull out your receiver and plug the amplifier's remote turn-on wire into the proper remote turn-on terminal of your receiver's wire harness.

  • In a rare situation, the remote turn-on wire input is touching the power wire, which can also cause this same issue. If this is what is happening, then simply take the remote turn-on wire out of the amplifier terminal and carefully put it back in so that it is not touching the power wire.

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