My honest suggestion....just get a set of decent co-axials for the rear. I'm sure the rear seat passengers aren't going to be critically analyzing the sound quality of your rear speakers. To the average listener, a decent set of co-axials will have more than enough "sound quality". This likewise solves some issues for you (like where to place the tweeters) and puts a little bit of money back into your pocket, by way of allowing you to spend less money on the rear speakers.
Bad idea....tweeter would be firing directly into the ear of the rear seat passenger. You would have to
heavily attenuate the output level of the tweeter in order for it to not cause severe annoyance to the rear seat passengers.
Not to mention the difference in distance and direction from the mid to the tweeter in relation to the listener would cause a very incoherent sound.
You are right. Much bigger problem with the distance and direction of the mid and tweeter in relation to the listener. Plus that would place the tweeter too close to the front seat passengers.
Not.
Why? A good component set properly powered and installed will get extremely loud. Adding more speakers only decreases the quality of the sound. More point sources for a less coherent sound. More phasing issues which will cause large peaks and dips in the frequency response. Lack of imaging and staging. The list goes on......
The most...
the most, I would possibly do is run a 2nd set of mids. And DO NOT place them in the middle of the car if you do this. Find a way to mount them either in the doors with the 1st set or in the kickpanels. Two sets of tweeters is completely unnecessary. Two mids will likely be unnecessary aswell however, and will sound horrible if done improperly.
Or, do as was mentioned above and run a 3-way component set. Just be sure to install them properly....with NONE of the speakers mounted in the middle of the car. Either the doors or kickpanels. Nowhere else.
Horrible location. Don't do it.
Unless you are able to run a processed center channel, that will do well more harm than good. Sound is stereo...separated left and right channels. Running non-center channel processed speakers in the middle of your car like that will completely screw up any sense of stereo separation you could have, making the music sound extremely unnatural and completely different than what the artists intended the music to sound like. It
will sound horrible. Imaging will be nonexistant aswell.
It may be "louder" that way....but it would sound horrid.
Horrible idea. Read the above.
Don't buy them in the first place.
Problem solved
That would sound even
worse.
Don't mix co-axials with components for the frontstage. On top of the problems I mentioned above, the relative difference in quality between the two speakers would cause sound problems.
Mixing components and co-axials for the frontstage and rear fill is a big of a problem (as far as rearfill goes, which I'm not a fan of). But don't mix them both into your frontstage alone.
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