That is true in some cases. A power cap will, in SQ based systems, improve the bass response of an amp up to a point. However once all the stored charge is discharged, the system will either be the same or even possibly worse than it was originally. A 2 farad power cap will indeed do a better job than a 0.5 farad cap due to being able to store more charge, but the same problem arises with both. For instance Phoenix Gold make a 15 Farad power cap for high end systems but after half an hour with long low bass tones playing, the capacitor is draining power from the battery to get its power back therefore hindering the system.
personally a larger battery with a good cranking amp figure would be a better investment. Something like an Optima or another Deep Cycle Battery for instance.
Russ
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