Question about Pioneer DEH-P7400 CD Player

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The bass box

I have wired up my amp and bass box to the head unit, but when i turn it on all my bass box keeps doing is thumping even if there is no music playin. everything to my knowlage is wired up correctly but i can't see why it is doing that. my bass box is bridged, but i can't see how that would have anything to do with that. hope you can help many thanks

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Re: The bass box

Hi Jamesroy,

Remove the Audio inputs from the bass box to see if the thump is coming from the Audio input. Of course do this with everything turned on. What we are trying to figure out is where the thump is originating from. If the bass box does not thump when the audio inputs are disconnected, the thump is coming from somehwere between the bass box and the circuits inside the head unit.
If you still have the thump after the Audio input wires are disconnected, then your bass box's amplifier has noise problem. You might try getting a noise filter from best buy to put on the power supply feeding the bass box.

Posted on Nov 30, 2007

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1) Understand the basics of all car stereo systems. A car stereo system consists of 4 main components and the wiring that connects them. These are the head unit, the main speakers, optional amplifiers and the subwoofers, which are also optional but generally considered a necessary part of any good system. 2) Know that the core of any car stereo is the head unit, which is the cassette or CD player that goes in the dash. All the other components are connected to the head unit by at least one pair of wires. 3) Know about car speakers. The main speakers are usually 2 in the front and 2 in the back, although with what are known as component speakers, each speaker is broken down into two speakers: one for the highs and one for the bass. Each speaker or speaker set (known as a channel) connects to the head unit via a pair of wires. Generally if you are installing a new head unit you want to install new speakers. 4) Know about amplifiers. Amplifiers provide extra power to your speakers and/or extra channels of power for additional speakers. The most common use for an amplifier (amp) is to power subwoofers. The amp connects to your head unit via an RCA cable and often a "remote on" wire, and also connects directly to your car battery through a fused "hot" wire and to the car's chassis with a short ground wire. This article assumes the use of a single amplifier connected to a pair of subwoofers. If you do not have these components simply ignore the steps specific to the amp, doing so will not affect the rest of your installation. 5) Know about subwoofers. Subwoofers are part of any good stereo system. They provide the deep bass that small speakers cannot achieve. Subwoofers are connected to the amplifier which can usually be mounted right to the subwoofer box. If you do not have subwoofers you can simply ignore the steps specific to them. FOR more help click on this link directly ------ This will help. Thanks please keep updated.please do rate the solution positively .thank you for using fixya

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