I have a 2002 Ford Expedition with factory mach audio system, which includes a head deck, 6-cd changer and sub-amp with small sub-woffer. I replaced all 4 speakers in the f/r doors. I hooked them up to a JVC 4 channel 550w amp for the doors... all works well. I am using the factory head deck but the sub amp located in the rear on the passager side fried a few weeks ago. I removed it and the factory sub-woofer and relaced them with a Boss Mono 850w (250rms) amp and infintity 10" sub-woffer and box. Because the factory head does not have low outputs (rcas) I spliced in the inputs to the Boss on the left & right rear on the highlevel input of the JVC. When activated the 10" infintiy bumps one time (like it should) and a very low output happens. I even wired it in to the JVC removing the rears and running with front door and the 10" in a bridge mono mode, same thing happens.
I first thought the speaker must be damaged (due to open box reduced price) but the local Best Buy says it's find. I would like to use the OE ford had used for the sub-woffer only it seems to only have one input verse two.
questions: will one input hurt the amp? can the head deck be pushing not enough current? I do have 5.6 volts at the boss input for both channels currently using.
how high is you gain set at? also your bassboost. your problem may be the cheap boss amp. your deck isnt the problem....... how many ohm is the amp and how many ohm is the subwoofer. what size wire is powering the amp?
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two 12" cadence TXW-12S, cadence TXA-3002 amplifier, 1990 toyota celica system 10 speakers
I have played with the gains both are setup half way at htis point bass boost is on +18v. yes the amp is low end it is a 2-ohm mono stable amp using a 10" infinity DV coil woffer I have tried hooking it up in 2ohm and in 4ohm mode but same results. I'm using an 8ga. wire direct from the battery its a run of about 16ft. I also connected the boss to the jvc amp in a bridge mono mode and it still does not have any volume or thump.
You mention the factory sub amp is fried. Do us a favor. Kill the bass boost, and turn the gain down all the way. Connect the factory amp inputs directly to your amp's low level (rca) inputs. This is a low level signal, and needs to be connected as such. Wire some rca ends on, and see what happens. You said there's only one input to the factory sub amp, so you can just split it so both the left and right channels of your amp receive signal. Now set your gain, etc.
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My ex once told me I have a perfect face for radio.