just added some component tweeters to the rear deck aiming them off the rear glass. I have noticed 2 things;1) ambiance has improved significantly...much more spacious sounding, and 2) The sound quality for the rear passengers is much, much cleaner, crisp and detailed than before. Try it, you might like it.

 

I hear you, man. I've tried it both ways in my car, and I actually like it better with rear fill. That said, I keep them at -10dB, and use digital time alignment to blend the rears in with the fronts. From the front seat, you can't tell that they are on, until you turn them off.

My last car sounded better without rear fill, though...

 

Why don't people like rear fill? I think nothing in the back sounds bad if I were to be sitting in the back seat. I dunno

 

As do I, but I dont usually sit in my back seat while driving, so its no problem.

 

lol I don't sit in the back while driving but I want everybody to enjoy the music.

 

^^that was one of the main reasons i decided to try it. I was driven home late one night and allowed an elder person to sit up front(mobility issue and i had a few drinks), i realized that the sound in the rear was relatively dull( unfortunately my 6x9's had to be mounted under the deck carpet, which blocked some of the finer, higher frequencies). Anyway, I decided to try some tweets and I have to say it was an excellent decision. As for those who don't like it...to each his/her own. I would say to anyone who has not tried it, do try, you may be pleasantly surprised.