i bought this speakers, polk 6.5 db651s

this.http://www.crutchfield.com/p_107DB65...lk+db651&ssi=0

i'm very noob about speakers installation, so what i did was removed the old bose speaker, and installed the new one, i plug the green wire to - and the purple to + (this is all to a oem factory stereo system, stock amp) i was not surprise by the sound even though i have not install the other 3 door speakers. by any chance i'm i doing something wrong and is this the way i'm suppose to connect them.

please remember that i'm a noob on