# Car Stereo Wiring to mon **URL:** \ **Category:** Factual Questions\ **Created:** [September 16, 2019, 8:45pm UTC](https://boards.straightdope.com/t/car-stereo-wiring-to-mon/840341 "2019-09-16T20:45:23Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![walkerhollis](https://avatars.discourse-cdn.com/v4/letter/w/b9e5f3/32.png) [@walkerhollis](https://boards.straightdope.com/u/walkerhollis)\ **Post date:** [September 16, 2019, 8:45pm UTC](https://boards.straightdope.com/t/car-stereo-wiring-to-mon/840341/1 "2019-09-16T20:45:23Z")
I have a factory created to location to add a speaker in the dash of my vehicle. It is mid-range. Ordinarily, this would be for a more costly separate amp setup. I would like to tap into the front left and right (before each speaker) and then run both left and right to the middle/mono dash speaker. The regular L & R will be pulling most of the power. Any issues feeding he mono speaker? I am not sure what is returned to the integrated amp over the (-) wires. Thanks! ---
**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\ **Post date:** [September 16, 2019, 10:03pm UTC](https://boards.straightdope.com/t/car-stereo-wiring-to-mon/840341/2 "2019-09-16T22:03:04Z")
I’d use a small amplifier with line level inputs to drive the center speaker. Otherwise, the left and right will be parallel and you’ll lose stereo sound. ---
**Author:** ![walkerhollis](https://avatars.discourse-cdn.com/v4/letter/w/b9e5f3/32.png) [@walkerhollis](https://boards.straightdope.com/u/walkerhollis)\ **Post date:** [September 17, 2019, 2:35am UTC](https://boards.straightdope.com/t/car-stereo-wiring-to-mon/840341/3 "2019-09-17T02:35:43Z")
Thanks for the answer. Interestingly enough I heard from Crutchfield that I can run the (+) right and the (-)left and it will not harm the integrated amp. He said this setup will bridge the left and right speakers into mono while also getting the input of the right speaker. ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [September 17, 2019, 11:18am UTC](https://boards.straightdope.com/t/car-stereo-wiring-to-mon/840341/4 "2019-09-17T11:18:00Z")
> [@walkerhollis](#): > > I have a factory created to location to add a speaker in the dash of my vehicle. It is mid-range. Ordinarily, this would be for a more costly separate amp setup. I would like to tap into the front left and right (before each speaker) and then run both left and right to the middle/mono dash speaker. The regular L & R will be pulling most of the power. This is a bit of a misconception. The size of the speaker isn’t what determines how much power it will “pull,” its impedance does. If you put a 4 ohm speaker in the dash and the door speakers are 4 ohms, they’ll draw similar amounts of current. > [@](#): > > Any issues feeding he mono speaker? I don’t think you’ll harm anything, but there’s a chance the additional unexpected load on the L and R channels might cause the amplifier IC to detect it as a short circuit and shut off to protect itself. > [@](#): > > I am not sure what is returned to the integrated amp over the (-) wires. Thanks! The vast majority of car radios have bridge-tied-load (BTL) amplifier chips with balanced outputs. Meaning, the chip has 8 amplifiers and each channel (LF, RF, LR, RR) uses 2, carrying the audio signal on its (+) wire and the inverse of the audio signal on the (-) wire effectively doubling the voltage across the speaker. ---
**Author:** ![Marvin\_the\_Martian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/marvin_the_martian/32/2898_2.png) [@Marvin\_the\_Martian](https://boards.straightdope.com/u/Marvin_the_Martian)\ **Post date:** [September 17, 2019, 12:53pm UTC](https://boards.straightdope.com/t/car-stereo-wiring-to-mon/840341/5 "2019-09-17T12:53:20Z")
A [dual voice coil speaker](https://www.retromanufacturing.com/blogs/news/dual-voice-coil-speakers) would be the way to go if you can find one that fits the speaker location. ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [September 17, 2019, 1:17pm UTC](https://boards.straightdope.com/t/car-stereo-wiring-to-mon/840341/6 "2019-09-17T13:17:46Z")
> [@Marvin\_the\_Martian](#): > > A [dual voice coil speaker](https://www.retromanufacturing.com/blogs/news/dual-voice-coil-speakers) would be the way to go if you can find one that fits the speaker location. the vast majority of DVC speakers out there are subwoofers. OP, can you share what vehicle you have? There might be a better way to do this… ---
**Author:** ![Marvin\_the\_Martian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/marvin_the_martian/32/2898_2.png) [@Marvin\_the\_Martian](https://boards.straightdope.com/u/Marvin_the_Martian)\ **Post date:** [September 18, 2019, 1:03pm UTC](https://boards.straightdope.com/t/car-stereo-wiring-to-mon/840341/7 "2019-09-18T13:03:25Z")
> [@jz78817](#): > > the vast majority of DVC speakers out there are subwoofers. The website that I linked to carries a large number of full-range DVC speakers. Seems to mainly be for retrofit into older cars with a mono in-dash speaker, so a size that fits the OP’s application might not be there. ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [September 18, 2019, 1:45pm UTC](https://boards.straightdope.com/t/car-stereo-wiring-to-mon/840341/8 "2019-09-18T13:45:52Z")
> [@Marvin\_the\_Martian](#): > > The website that I linked to carries a large number of full-range DVC speakers. Seems to mainly be for retrofit into older cars with a mono in-dash speaker, so a size that fits the OP’s application might not be there. then you’re putting two more 4 ohm coils on the front left and right speaker channels for a 2 ohm load. Again, the radio may detect that as too low an impedance and trigger its short circuit protection. if it doesn’t, it may not have the thermal capacity to deal with the extra heat.