Question about Rockford Fosgate Punch 800a2 Car Audio Amplifier

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No sound output from amp.

There is no sound output from my 800a2 regardless of input level from the source unit. The amp is getting all the proper voltage, remote lead, ground, source signal, etc. the power led comes on, and the amp itself is drawing 15 amp's at idle. (increasing input voltage does not change the amp's current draw.) I checked all the switches, gains, etc. I took the amp apart and inspected everything visually, everything looks like new, no burnt smell. I am pretty handy with a soldering gun and a v.o.m. Do you have any ideas or suggestions for me to try?...THANKS..

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Re: No sound output from amp.

It has bad parts. It should NOT be drawing 15amps at idle!! You need to grab a DMM and check the mosfets!!

Posted on Nov 02, 2006

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Another conundrum

To check for yourself, get an Ohmmeter and see if the outers of the amplifiers RCAs are connected to the ground or each other. If so then it cannot take speaker signals directly.
I suspect the 'High Level' the manual speaks of are the 4volt auxilliary audio signals that can be found on some newer head units, not speaker signals.
Speaker level signals from a bridge amp CAN be used on grounded RCA inputs if the signal is first passed through a simple decoupler and attenuator.
Diagram to explain....

Nov 22, 2007 | Infinity 475A Car Audio Amplifier

1 Answer

Cant get no sound

Try a different input source. I have had this happen before and the easiest way to diagnose the root of the problem was to take a home CD player out to my car and use the outputs to power the amp. If the amp works, move upstream to the RCA wires (unplug them from the back of your head unit and plug them into the home CD player). If that works, you know the stereo isn't putting out a signal. Good luck!!

Jan 26, 2010 | Alpine MRD-M501 Car Audio Amplifier

1 Answer

Bought a Alpine PDX1.1000. 1 - 8v issue

Hello rsnyder_223,

As long as the gain is adjusted properly for the input, there should be no problems with the amp.

The head unit preamp output is probably a little low or there is too much voltage drop on the RCA's. It doesn't take much of a drop when you are working with such a low level to begin with. That's one reason that Alpine gives you the option to select an input level.

It's also possible that the input sensitivity of the Alpine is slightly high. Electronic components usually have a nominal value and their actual value can range up to 20% from that nominal. But again, you have a gain adjustment to insure that the amp is not overdriven. Make sure that it's set so there's no distortion and you should be OK.

Hope this helps.

Aug 23, 2009 | Alpine PDX-1.1000 1000W x 1 Car Amplifier...

1 Answer

I have a Boss OL5KD Class D Monoblock Amplifier and I set it up but is no sound coming up from the speakers, can anyone tell me how to higher the volumen? where is located the volumen??I need to higher the...

Hello maydude01,

The Boss OL5KD does not have a volume control. It has an "Input Level" adjustment which is used to match the output from your head unit preamp output to the amp. It is the first rotary control just to the right of the input jacks.

If you have no sound at all, I'd suspect that something is incorrectly connected or there is no input to the amp. First make sure that the amp power light (green LED) is coming on when you turn on the receiver and that the protection light (red LED) stays off. Then check all of your wiring, especially the RCA output cables.

Initially set the controls like this: MASTER/SLAVE switch in MASTER position (left). INPUT SENSITIVITY 2v-8v (right). INPUT LEVEL, SUBSONIC FILTER, BASS BOOST, and LOW PASS FILTER; midrange. PHASE SHIFT "0" (left). Leave the remote level control disconnected.

After you've checked all wiring and initially set the switches and controls, turn the receiver on to about 3/4 volume. Now adjust the INPUT LEVEL to the left just until you begin to hear distortion, then turn it back right just a little. Adjust the other controls for best sound. Plug in the remote level control and make sure that it adjusts the bass up and down. You're finished!

If there's still no output from the unit after checking all of the wiring, either the unit is defective, it's not getting an input from the receiver, or the sub(s) are defective.

Hope this helps.

Aug 14, 2009 | Boss Car Amplifiers

1 Answer

Can't get sound to speakers

No preamp required. I just repaired one I got from Ebay.. There are a lot of buttons on the unit and you need to have several of them set correctely to get output. This is a powerful amp and you can blow speakers easily so be careful. Make sure the standby switch is up. Most important: The slide switch should be clear UPWARD to the L/R speaker position.
The white trim control(s) need to be up to match the input source levels. Advance the faders for the cahnnel(s) being used. Advance the MAIN to control overall volume. That should get you started.
MAKE SURE your source is plugged into the CORRECT input jack as there are "inserts" and you will get not output or very weak output if you are in the wrong jacks.

Jul 14, 2009 | Behringer POWERED MIXER, 20 CH, 400 WTS...

1 Answer

What to do

Hello dodgeram1980,

If you are not getting sound from any of the 4 channels, I'd suspect that either the amp is not getting an input signal or the amp itself is faulty.

Here's the "no sound" troubleshooting step-by-step procedure from the JL manual:

1) Check the input signal using an AC voltmeter to measure the
voltage from the source unit while an appropriate test tone is
played through the source unit (disconnect the input cables
from the amplifier prior to this test). The frequency used should be in the range that is to be amplified by the amplifier (example; 50 Hz for a sub bass application or 1 kHz for a full range / high-pass application). A steady, sufficient voltage (between 200mV and 5.O-volts) should be present at the output of the signal cables.

2) Check the output of the amplifier. Using the procedure explained
in the previous check item (after plugging the input cables back into the amplifier) test for output at the speaker outputs of the amplifier. Unless you enjoy test tones at high levels, it is a good idea to remove the Speaker Connector Plugs from the amplifier while doing this. Turn the volume up approximately half way. 5V or more should be measured at the speaker outputs. This output level can vary greatly between amplifiers but it should not be in the millivolt range with the source unit at half volume. If you are reading
sufficient voltage, check your speaker connections as explained below.

3) Check to ensure that the speaker wires are making a good
connection with the metal inside the Speaker Connector Plugs. The speaker wire connectors are designed to accept up to 12 AWG wire. Make sure to strip the wire to allow for a sufficient connection with the metal inside each terminal.

Hope this helps.

Apr 30, 2009 | Jl Audio HD600/4 Car Amp

2 Answers

I got 4 ''15 inch kickers 2 5500watt power acoustik mono amps my problem is 2 kickers on the right side hittin hard but the 2 on the left not.i thought the amp on the left was bad so i took the rca of the...

Hello herb31,

It sounds like there is a difference in the signal levels on the inputs to the amps. You did not specify what the RCA's are connected to on the head unit side. If they are connected to a stereo pair of preamp outputs, you may be able to solve the problem by using only the channel with the higher signal and use an RCA "Y" adapter to split it to both amps. If they are connected to a dedicated subwoofer output on the head unit, make sure that the head unit is set for "subwoofer". Some less expensive head units, I know JVC in particular, has only 1 set of line outputs and requires you to go into their "PSM" (Preferred Setting Mode) to set the line output mode and if you select "subwoofer", then allows you to select the low pass frequency.

If you are converting speaker-level outputs through a "line out converter", check both the input and output levels.

Also, if you are splitting an output from the head unit, you still need to connect 2 RCA's to the amp inputs. The signal will be properly split if you use a 1-female to 2-male "Y" adapter. To feed the same signal to both amps, you would need 3 "Y" adapters. Feed the output signal to the female end of the first "Y", and plug the male ends into the other 2 "Y" adapters. Then, the 4 plugs you have left on the ends go into your amp inputs.

Hope this helps.

Apr 24, 2009 | Power Acoustik CLASS D SL-5500D Car Audio...

1 Answer

Fan on amp runs constantly. will this drain my battery?

Yes, and would imply that the amp is powered up all the time.

You should correctly wire your system by

1.Connecting the constant 12vdc input wire to a constant 12vdc source to power the in-dash head units memory.

2.Connecting the switched 12vdc input wire to a switched 12vdc source to power the head units primary functions.

3.Connecting the remote output wire (typically a blue wire) from the in-dash head unit to the correct terminal on the amp, so the amp will only power up when the head unit is on.

4 Remember to run the signal (speaker) wires in a chase separated from the amps power wires, so as to avoid a buzzing noise in the speakers.

5. Always use an in-line fuse on the amp and the head units main power wires.

Note: A properly powered amp will produce a better sound quality then if it were under powered, so be sure to use the proper wire gauge as your amps power supply.

Good luck

Mar 22, 2009 | AudioBahn A2002T Car Audio Amplifier

1 Answer

Sony xplod amp xm-1652z high level input connection

First off, if you're using RCA preamp connections from the head unit to the amp, you don't need to put anything into the high level input connector. But if your head unit doesn't have RCA preamp outputs, then connect the front left to the white (+) and white/black stripped (-) wires and the front right to the grey (+) and grey/black stripped (-) wires. There is no need to connect the rear speaker outputs of the head unit to the high level input of the amp.

Apr 17, 2008 | Sony Xplod XM-1652Z Car Audio Amplifier

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