i have 2 alpine type rs hooked up to individual amps
when i play music with the car off its fine
then when i turn on my car it seems to make the subs move all weird
whats causing this?
i checked my ground and power wires they seem to be fine.
also when i turn the volume more then half my amps shut off completly
but my interior amp and speakers are still working.

 

Check the gains on your amps. If they're shutting down, it's usually because of a protection circuit of some kind, whether it be thermal etc. Plus the speaker pop you're seeing could still be grounds, anywhere from the amps back to your deck.

 

can you please list model of subs and amps you are running?
my guess is that you are running amps of lower ohm's then they can be ran at and once you turn it too loud protection shuts them off
i had same thing when i tried bridging amp to 1 ohm and it wasnt 1 ohm stable.

 

thats probably your problem

or you have a bad ground....make sure the metal you ground to is actully well connected to the chassis of the vehicle and its not jsut some support bracket holding some plastic parts in place

made that mistake once

 

i am running 2 12 inch alpine type R`s with 2 alpine pdx 1.600
these amps can run at either 4 or 2 ohms
and i have each amp hooked up to there own sub
these subs in no way are hooked up together
and in the wiring diagram that alpine has i have them wired at 4 ohms
but these speakers are 2 ohms
i also have one capacitor hooked up to just the one amp and not bot
could this be creating the problems

 

that really sounds like a issue with one of your rca's or teh splitter that your using try just running one amp at a time, there also might be a issue with one of the non fading outs on the amp

 

with a capacitor on only one of your amps you will be expieriencing voltage drop in one compared to the either, small or large, it makes no difference as your amps are not both running at the same voltage... therefore they are not outputting the same power... best advice would be redo your wiring for your amps

 

i bet you 5$ you got SWR-1221D = 2 ohm per voice coil and coils connected in parallel = 1ohm

it doesnt matter what you amp is stable to 4 oh 2 ohms what matters is how you hookup subs to it.

example:
dual voice coil sub with 2 ohm per coil can be hooked up :
parallel = 1ohm
series = 4 ohm

dual voice coil sub with 4 ohm per coil can be hooked up :
parallel = 2ohm
series = 8 ohm



ALSO you say subs move all weird. my guess is that you got subs hooked up wrong and they move opposite directions. try reversing + and - for one of the subs and see what happence. also I had same problem rofl :S

 

decribe the weird thing it's doing!
are the subs sucking in and out and making a "thunk" or popping sound?
if so it's GROUND related.
check your connections on the amp connector for ground
check connections where ground cable is mounted to metal
check ground connection on battery terminal to battery
check ground wire off battery to car body
look for rusted, loose, corroded connections or in splices in your wiring.

 

Does it make weird noises when u skip tracks or adjust volume and stuff like that? My guess is grounds or RCAs just like mentioned above. If it makes weird noises when skipping tracks or things like that on the deck then i would blame the deck's ground or RCAs for that part.
Also, feel the amps and see if they are getting hot quickly. Although sometimes you wont actually FEEL the heat of the amp so much. I had an amp brought to me by a guy at work who claimed it never heated up at all but cut out all the time as if it was being loaded down too far or getting too hot. It turned out someone had serviced the amp at some point in time and forgot to screw down the transistors to the heatsink of the amp. The result was overheating transistors causing the amp to think it is overheated. Im surprised this didnt kill his amp almost instantly. Its the whole reason amps even have heatsinks.