4" vs 6.5's

Bryn Mountford Silver Member Username: Brynm Prince Albert, SK Canada Post Number: 140 Registered: Jul-05	Posted on Friday, January 06, 2006 - 00:24 GMT how much difference would i hear if I have a set of 4" up front and 6x9's in back vs. 6.5's up front and 6x9's
ty mutlow Silver Member Username: Tjmutlow Post Number: 856 Registered: Sep-05	Posted on Friday, January 06, 2006 - 00:34 GMT enough to use 6.5 if you can fit them