Used to have b, now there isn't any?

i have a 97 4runner limited with factory sound which included an in-dash 3 disc changer with a small amp connected to it also in the dash, and factory speakers, but its original equipment so its 13 years old. the b wasn't too bad, i just wanted a new deck that played cds and was ipod compatible. i bought an alpine cda 105 deck and had it installed, kept the factory speakers, and i figured the sound would be as good if not better. but there is absolutely no b. it can get loud, but with no b. the original equipment sounded clearer and had b that would blow a speaker if the volume was loud enough. now, with this alpine deck installed, the sound is garbage. i've played with the b and treble settings, the defeat, the loudness, all of it. any help would be great? could the installer have hooked up the speakers out of phase? do i need an amp even though the alpine cda 105 has its own amp?