truck stutters when bass hits

been in business 20+ years and have never seen this.. need help got a 1991 Chevy truck basically when the bass hits.. the truck stutters to the beat.. not a lil bad enough to sometimes kill the truck. now the setup under hood 2 Optima batteries. stock 110amp alternator for those. in rear 1 optima battery hooked directly to my PB 5k amp another 110a alternator powering it directly now the riddle. the system battery is not hooked to the vehicle electronics at all. however when the truck stutters, I can see the volt gauge (aftermarket) drops volts from the vehicle batteries.. how in the hell can it do that. secondly.. it goes from system alternator to 200amp breaker.. then to system battery. if I pop the breaker. the truck will not stutter.. however with it popped rear battery receives no charge. somehow its drawing from the truck electronics. and I cant figure out how where or why.. please advise.

So you are not charging the audio Optima? (It is totally separated fro, the alt & main battery(s) and non-auto electrics.) Maybe insufficient grounding between engine-chassis-main_battery or shared audio grounding - ie- using audio sharing with main.

oldspark wrote: So you are not charging the audio Optima? (It is totally separated fro, the alt & main battery(s) and non-auto electrics.) Maybe insufficient grounding between engine-chassis-main_battery or shared audio grounding - ie- using audio sharing with main.

ok, the audio optima has its own alternator.. and is not connected to anything else.. truck will stutter, but if I break the fuse from alternator to batter the truck will run fine. however the optima then is not charging also for grounds. not sure if that would be issue. as amp is grounded rear battery is grounded. and I have grounded numerous places through out truck.

What have you done to add to the engine-chassis/body grounding?

Each alternator has a 4 ga ground Each ground strap has been redone. Also added 9 new 8 ga grounds throughtout body and frame

are your alternators internally regulated or do they have external regulator packs to control them? where did you tap for the field wire of the alternator for your audio?

Also, how is the engine driving the two alternators? Same belt/pulley or completely separate setup?Support the12volt.com

If grounds are good and since disabling the audio alternator solves the problem, I'd suspect its purely mechanical and needs to be treated as if it's an aircon.

soundnsecurity wrote: are your alternators internally regulated or do they have external regulator packs to control them? where did you tap for the field wire of the alternator for your audio?

internal, stock 1 wire chevy alts

DYohn wrote: Also, how is the engine driving the two alternators? Same belt/pulley or completely separate setup?

my truck doesn't have ac, but has a spot and pully for the upgrade so I mounted it there.