Car Stereo Replacement in RV Problems

Shot in the dark: Not sure of the age of the one you replaced but older car stereos used ground for the common wire to each speaker. New ones do not...2 wires must be run to each speaker and neither are grounded.

The reason they wired them together (parallel) is because they're 8 ohm speakers and it's hard to get any power out of a car stereo without 4 ohm speakers.

. For some reason, they had wired the Front and Rear speaker outputs for each side together, something most Audio people will tell you not to do.

you did not do that did you? make sure the front to rear fader control is set to the middle or front or rear which ever connections you hooked the speakers to. most car stereos now have 4 amplifiers in them and you cannot hook the front and rear together.

Just as ScottG said, you could have a mismatch of speaker impedance vs amplifier impedance. The stereo will have this shown on the identification sticker somewhere on the case, and look something like 2-4ohm out 4-8ohm, ect. The speakers will also have a sticker on the magnet indicating 4, 8, ect.

If the impedance between the two are not matched, you will have lower sound quality and increased amplifier heat. Two 8ohm speakers being wired in parallel equals a 4ohm load, which would match the stereo amplifier impedance rating.

Check these numbers and you may need to modify the speaker connections.

Hey thanks all for the replies. I had a "DUH" moment and measured the resistance of both speakers, they are both shorted.

Mike D.

My guess is the original radio was low power two channel type and had built in fader control. Since your outside radio has only two speakers it does not need fader control. So in order to hear sound from both speakers in any position of fader control they connected output for front and rear speakers together on both left and right channels. This is commonly done and is OK.
Most radios today are high power BTL type with four separate amplifier outputs and built in fader control. None of the speaker output wire connections are grounded and MUST NOT be grounded. Each speaker has to have separate twin line.
There are just too many different scenarios and all depends on a particular model off the radio you have.
The instructions that come with a radio tells you what you have and how to wire it.
Your speakers might be shorted but also may not be-depends on the meter you used.
Good luck