adding an amplifier for sub question...
#1
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I have an 06 with the Mark L. stereo, I am planning to add an amp and subwoofer. I am aware that I would typically need a line converter to tap into existing speaker signals-convert to low-level rca and then hook up to the amp, then the power wire, ground, and remote turn on. My question is, is there an existing unused set of rca outputs somewhere to run directly to the amp? And/or, if I have to use the line converter, where can I tap into the speaker signals for this amp? Can I somehow use any of the wiring that goes to the factory sub? Thank you all in advance.
#2
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I haven't attempted this myself yet, but I will share some research I've done during investigating a similar upgrade.
First off, I found this schematic diagram package to be invaluable; LINK
If you look at page 26, it provides the pin out definitions for the 3 sub connectors on the back of the head unit. Subsequent pages also go into detail describing the terminals on each components main board. I do believe you should be able to "split" these Lch/Rch speaker outputs, at the harness, which should be pre-amp level at this point, and use it as the source feed to a new subwoofer (no line level correction needed). Note: that it appears these signals are BALANCED at the head unit terminals, so you will need to either unbalance them (not preferred) or find a sub-woofer amplifier which can accept the balanced input (preferred).
First off, I found this schematic diagram package to be invaluable; LINK
If you look at page 26, it provides the pin out definitions for the 3 sub connectors on the back of the head unit. Subsequent pages also go into detail describing the terminals on each components main board. I do believe you should be able to "split" these Lch/Rch speaker outputs, at the harness, which should be pre-amp level at this point, and use it as the source feed to a new subwoofer (no line level correction needed). Note: that it appears these signals are BALANCED at the head unit terminals, so you will need to either unbalance them (not preferred) or find a sub-woofer amplifier which can accept the balanced input (preferred).
Last edited by z0lt3c; 01-02-12 at 07:57 AM.
#3
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wow, thank you for that link.
I am thinking that I should be able to tap into any of the speaker signals from the amp under the seat. If I am correct, I can just splice into let's say the rear speakers-from the harness that goes from the amp to the speakers, and use the left and right signal to plug into the low level, rca, converter, that goes directly to the rca input of the aftermarket amp. Then just tap into a remote turn on wire, then power and ground, then the wires from the aftermarket amp directly to the sub. Does that sound about right to you?
I am thinking that I should be able to tap into any of the speaker signals from the amp under the seat. If I am correct, I can just splice into let's say the rear speakers-from the harness that goes from the amp to the speakers, and use the left and right signal to plug into the low level, rca, converter, that goes directly to the rca input of the aftermarket amp. Then just tap into a remote turn on wire, then power and ground, then the wires from the aftermarket amp directly to the sub. Does that sound about right to you?
#4
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The only concern I have with splitting the signal post amplifier would be if the amplifier implements any kind of frequency based filter or other kind of sound modulation. I have not found the schematic of the amplifier, or opened up the speaker locations yet, but there must be a crossover somewhere in the factory system to support that many speakers.
By taking the pre-amp balanced signal from the head unit, you don't need to convert to line level or worry about a modified signal.
By taking the pre-amp balanced signal from the head unit, you don't need to convert to line level or worry about a modified signal.
#6
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I found out some more info. another person tapped into the signal from the front left channel for one channel on the 2 channel line output converter (LOC) and then used the signal from the factory subwoofer for the 2nd channel. The idea behind this was to allow the aftermarket subwoofer a little more range in the frequencies. The factory sub goes from about 30hz to 80hz aparently, and the front speaker (mids) go up to about 100hz. So, I think the idea was by tapping into both signals, it would allow the aftermarket sub to go from 30hz to 100hz. Does that sound like it makes sense to anyone else? It seems to be logical to me but am I missing something?
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qha_vn
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07-21-09 04:14 AM