Audio Systems: Battery Wire, amp fuse, fuse size

Question
I'm not getting power through my battery wire apparently. If i splice the ignition wire and the battery wire together i can get the stereo to work but the memory is erased everytime i turn the car of. Any reasoning i am not getting power from the battery? i actually believe when i started the day i was. Could i have shorted a fuse or even ruined the wire?

Answer
Most likely a blown fuse, either under the dash (fuse box) or under the hood (fuse box or fusable link). The wires are pretty tough, so rarely are they the problem. If you absolutely can't find a blown fuse, just run a new wire and fuse holder from the fuse block, or battery. Make sure the fuse is at the beginning, not the radio end. 15 amp fuse size is usually lots.