Originally posted by SupraKid
"Lights dimming" when the bass notes hit is a different problem, and is caused by the battery and alternator not keeping up to the transient demands of the system. For this kind of problem, a capacitor will do an excellent job of helping the problem by evening out the system demands. Increasing alternator output has little or no effect on this problem.
elementary physics disagrees with you. lights dim because of an amp drawing more current than your electrical system can provide at a given moment. if your alternator puts out higher current, then you won't have that problem.
EDIT: just look at any db drag type competition vehicle. most of those cars have power demands that would cluster fuck your little stock alternator and cap. the vast majority (if not all) run without caps and do just fine.