eCrack you think floating voltage = floating charge? Do I really need to expain the difference????
Let me explain it to you in easy terms so you can attempt to grasp this simple info. At 12.6v a batts floating voltage = resting voltage (batt with 0 load). When charging a batt the floating voltage is higher than 12.6v.
Now when an alt is charging a batt, lets just say its charging it at 50A. Now when you hit a quick bass note that makes your amp demand 100A of current. 50A will come from your alt, and the other 50A will come from the batt. If the load is quick enough, your voltage will NOT drop below 12.6v. The alt is not fast enough to change its output dynamically based on the load from the amp. (oh crap, I think this last sentance was over your head)
I said the batt CAN and DOES provide output at above 12.6v. Obviously it will only be for a very short time.