sup
I have a 400watt amp powering two 10" JL subs, for some reason when im playing at a moderate volume the subs suddenly gets weaker ( lower ) and then later comes back normal.
Im pretty lost when it comes to audio lol.
anything i should look at?
Thanks

 

your battery is dying, try getting a battery recharger. they should have em at best buy in the car audio section, or pick one up at a car audio shop

 

i think he is refering to a cap... but a cap wont solve your problems... when the subs shut off or get lower have you ever looked at the amp or touched it??? what kind of amp is it and what kind of subs do you have a few more specifics and we might be able to help you...

did you install the system or was it done by a pro???

what i would think is that either the amp is getting too hot or is going into protection...

but i need a few more details to know what is happening...

 

also, check the power connections from the battery, then check the connections to the amp. Make sure all wires are FIRMLY and COMPLETELY connected, not loose.
Check amp/head unit settings.

If that all checks out, i would try buying a new battery.

 

I have the JLW0's
me and a friend did it, pretty good job, double checked everything to make sure lol hes also pretty experienced with audio work.
dont think its the batt. had it for like 2 months lol.
i think the amp is getting hot, i mounted it on top of the box, the thing is the box is alittle bit high, so it touches the hatch cover.
ill try mounting it somewhere else. thanks for the info, anymore would be cool
thanks

 

i never understood why people mount the amp on the box. that is just another way for air to leak out of the box and lower sound quality. anyways
check your ground. it might be comming loose. it happened to me, i was driving and my subs were getting lower and lower then it just shut off. i looked and my ground had come off.

if it is not the ground, then it might be the battery or safety mode on the amp

 

^ agreed... my first guess is inadequate cooling for the amp

 

I mounted my amp on the back of my seat with some 3/4" screws.
Check out my cardomain to see how. The amp box also covers it, to keep it shaded. No troubles yet, although its only a week old.

Just an idea for a mounting position.

 

i would say that it IS your electrical system, because even though the battery is new, your system may not be charging as it should. My acura's alternator will handle my alpine MRV-1507 up until about 800w RMS, then the lights get really dim, and the spedometer drops a little and the tach drops ever so slightly... my point is, your battery can be only 5 minutes old, but if your stereo is pulling more amps than your alt can handle, your gonna drain till you reach equilibrium... just my 2 cents

 

would a new alternator fix this?

 

also, some days the subs work really great, never turning low, and some days they act up lol weird
thanks