Help with new 6x9's and Bose amp
 

I replaced the original Bose 6x9's on the back shelf of my coupe today with Infinity 6929i's. If I unplug the rear side 6 1/2's and fade the music to the new Infinity's they sound horrible.
My two questions are,
does the original Bose amp send only a low frequency to the rear shelf speakers? I can't think of any other rearson they would sound so crappy.

Also, for now, is the solution to disconnect the OE rear 6 1/2's and run the new Infinity's off of those wires, hoping to get a full unfiltered frequency the new speakers?
Any help would be much appreciated. And yes, the next step is a new amp, just don't have the time or cash to do it now.

Yes, the Bose amp sends only low frequencies to the 6x9s. Also, the Bose 6x9s are 2 ohm. If you got 4 ohm Infinity speakers, they won't be as loud as the Bose speakers were.