rear channels in mono

I'm running 2 4-ohm speakers in the front and 2 4-ohm speakers in the back, using a 4-channel amp. If I want to have the rear speakers be mono which of these wiring configurations should I use?

1) Wire one speaker to each rear channel. Run one jumper wire to connect the two rear positive terminals, and run one jumper wire to connect the two rear negative channels.

2) Run the two rear speakers bridged, in series.

Will configuration #1 damage the amp or the speakers?

If you want your rear channel to be mono (WHY?) the safest way is to connect each speaker to its own channel of the amplifier and then connect the same input signal (on the RCA side) to both channels.

1) above will short out your amlifier and blow fuses or worse, and 2) above would work but is not necessary.

I'm glad I asked before trying #1.

The reasons I'm wanting to run the rear pair of speakers in mono:

1) There's something wrong with my factory radio. The right rear channel is almost all bass. I've tried switching speaker wires, RCA cables, etc. It's definitely the radio doing this. Also it's not a problem of the speaker wires being hooked up out of phase. I figure it would be easier and cheaper to have mono in the back than to send the radio in to the dealer for repair.

2) I read a bit on sound staging (? correct term). At one site the feeling was that rear speakers aren't really necessary in the first place, and that rear speakers played in stereo shifted the perceived sound source left-right as well as front-back. This site recommended playing the rear speakers in mono if you were going to use them at all. I was interested in trying mono to see what it sounded like. If I can find the site again I'll post a link to it. I'm going to bridge the speakers this evening to see what it sounds like. More evidence I have too much time on my hands, I guess.

Here it is: http://p079.ezboard.com/fcaraudiotalkfrm27.showMessage?topicID=51.topic

BTW, any clues as to why all my posts have < language=>postamble(); at the beginning or end of them?

In a properly designed sound system (car or home) the main sound source should originate from in front of you, similar to if you were facing the stage at a concert performance.  "Sound Stage" refers to this "sourcing" of sound.  In a car, it is incredibly difficult to achieve proper sound staging since the ideal location for your speakers would be on your hood with the windshield removed.  Not entirely practical.  :)  The dominant (and best quality) speakers in a car audio system should be installed in the front of the car.  Rear speakers can serve several purposes, including adding ambience or depth to the sound stage (especially in a surround-sound system) or serving as the main listening source for passengers sitting in the rear seats.  For stereo listening in the front seat(s), rear speakers should not be noticeable.

Whoever said using a mono rear channel is a good idea is missing the point.  Mono will not ad ambience nor will it sound "good" to the rear seat passengers.

If your factory radio is giving you defective sound, get it FIXED.  Trying to finese it will only mask a problem that will probably get worse over time.

fix a factory HU??   noooo, pull that thing out and let an aftermarket take it's place for awhile.

maybee someone here will be kind enough to sell an old HU for $50 or something. No need to go through all of this when you can start fresh.