Plater 10+ year member
Member
I would have to agree with starting at the battery connections. A good quality ground wire from the battery to the engine and chassis is only going to coast 10 bucks or so and a little time. You might even get away with cleaning the metal surface that the ground wire connects too. That is the cheapest way to go first. Try it, it won't cost much see if there is an improvement. If there isn't then a new alt. or rewound alt could fix your problem. Because if you draw more current then the alt. provides the battery drains and voltage drops due to a litte thing called source resistance. If money is a problem look for high current rating alt. that are after market replacements. They won't be labeled HIGH OUTPUT but if they are rated higher in terms of current they should help. You could go to a car wrecker and look for bigger alt that are out of bigger cars, trucks that might fit in with little modification. A cap will only help if the alt has enough time between bass hits to recharge the cap from the last bass hit. You could try making the charging wire from the alt heavier gage wire so that there is minimal losses between it and the battery. Take a look at all the heavy gage wire conection to make sure that they are good and clean. Clean them up and cover them with a good conductive grease. A bigger battery could help assuming that the alt. can keep up with the loading.