why are the fuses blowing?

Back up the bus, you are running a Rockford 1501BD on a 50 amp fuse. If this is the case the fuse size you have chosen is waaaaaaay to small. A fuse size of 140 amps minimum is more along the lines of what should be used. This amp if it is the one I think it is, is a monster amplifier that has a big appetite for current, what size power / ground wires are used? Where is the ground run to, what kind of car is it in?Top Secret, I can tell you but then my wife will kill me.

its on a mitsubishi eclipse, my plans right now is to have two amps (1501's) and two MTX 9512-44.  ground/power wires are 4ga.  should i use two 140A fuses or what do you recommend?

Where is the ground wire run to? Have you upgraded all the factory ground / power wires from the alternator to the battery and battery to chassis yet? A 4 gaugs on that amp is almost a little too small for most cases. However in yours if you do not have a HO alternator then your hopes of using two of these amps properly is a long shot. An amp cannot make power unless it is given power. One fuse at the amp and another that is one the main power line within 18" of the battery is pretty much a must. The first fuse at the amp is for the amp, the second fuse is to protect the wire from a short circuit.Top Secret, I can tell you but then my wife will kill me.

actually, no, i haven't upgraded non of the alternator wires, i wanted to upgrade my alternator,but i have no idea on how or what to buy, damn seems like i have a whole lot to learn!   the ground is about 12" from the two 1 farrat caps that i have, and its grounded right on the nut where the seat belts are. appretiate your help man!