How do I hook up a small sub without an amp?

[Stephenwisham]

I was at my local pick n pull today looking for some used aftermarket 6x9's for my car and came across a Lexus with a small stock sub in the back deck. Nothing special, but I thought if I could add it to my current stock system, it may give me a little bump. I'm not looking to rattle my truck. I have a 4 month old and just wanted a little more bass than the 6x9's can give. I hooked the sub to one of my rear speaker wires to make sure it worked and it does. Actually sounded decent for not being amplified. I want to find a way to mount it in between the 6x9's in the rear deck without an amp, just wired from the head unit. My question is is how do I get a left and right signal. I could just hook it up from one speaker but it won't be in stereo. Is there a way to use both the left and right outputs in the back to get stereo sound? Wired directly or with use of a small electronic device? I don't care to use an amp and my head unit is stock so there aren't any options that I know of there either.

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[Papermaker85 5,000+ posts]

Bass is mono. Hooking it up parallel with one of the 6x9s is your only real option..

 

[Stephenwisham]

So one wire from head unit to positive post on 6x9, then a jumper wire from negative post on 6x9 to positive post on sub, then connect the other head unit wire to negative post on sub right?

 

[Papermaker85 5,000+ posts]

Positive from the 6x9 to positive of the sub. Then negative from the 6x9 to the negative of the sub. Aka parallel..

 

[Stephenwisham]

Ok.

 

[Vocaloid]

Careful when playing with impedance though. If the stock head unit can only handle 4 or 6 ohms or something, then you add another 4 ohm load in parallel, the load can drop too far on that channel and cook yer amp //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif.

Best situation would be if it was a DVC sub, identical impedance per coil, low power handling (matches low output of head unit), in a bandpass box (naturally filters out the highs)... then you can drop the factory speakers and just run a sub on the rear channels - and using the fade control match it to your front speakers //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif. I'm considering that myself but I've got the same problem you have right now.