Stick one of these in the box, but the battery only last 5 days.
 
http://www1.brickhousesec...a-logger-tracking.html
 
Bunch more here
 
http://www1.brickhousesec...g-vehicle-logging.html

Tint your windows so nobody can see them
 
Gotta car alarm at least??

This mite help you out but what you can do is to hide it if you can! http://www.dynamicsubwooferenclosures.com/catalog/index.php

Seems like you live in a high crime rate area... unfortunately there's not much you can do to prevent theft in that case. Unless you're willing to spend some bucks on security systems? Cameras? Where do you park your car at night, during the day etc?

Then you can exercise your 2nd amendment rights when you find them.

If a fiberglass box costs as much as your setup, I'm going to assume you didn't spend too terribly much money for your total setup (taking a guess at about $500-$1000?). Is this system really worth paying for an expensive GPS or alarm system that you may never use?
 
In my opinion your best bet here is not by buying a product for this. I mean yes, I have seen some nice security systems with  6 seperately wired 150db sirens inside the car underneath the interior run on backup batteries inside the car, but that was to protect a car with a $10,000+ system. Instead, I'd say a little bit of common sense here can go along way. Don't mount your amp in your back window, don't put stickers in your window like "Alpine" or "JL", don't park in areas with a high crime rate if you can help it (and if you do have to park there, don't bump within 4 blocks of that parking spot), don't brag about them to anyone your might not trust, put the subs in your trunk and not your back seat, be sure to screw them down (so if anyone actually does get in it'll take them that much longer to gets subs/box out of your car). The only thing I actually would recommend paying for would be some dark tint (5-35%) so no one can actually see in your car. Even when professionally done, this shouldn't cost more than $300 for 5 windows.
 
Also check with your insurance company and see what there policy is on theft. Some won't cover your system and some only will if it's part of the vehicle (bolted down). If it is covered by insurance, be sure to have pictures/video of the system and copies of receipts in case anything were to happen.
 
Another idea on the cheap: wire in a little red LED on your dash that blinks every so often. Someone looks in and sees that and they think you have a big fancy security system while you really only have a $5 circuit wired to a LED. Edit: Oh hey, look what I found.

Tweaked

My best advice!  Only bump on the open roads.  Never bump in parking lots, your apartment complex, or residential neighborhoods.  I have had competition systems in cars with no security systems, and never even had an attempt to steal my stuff.  The reason is because no one knew it was there.  Also, if you have a garage, park in it.  

I currently have a Viper alarm installed with a proximity alarm, and I park less than 20ft from my bedroom, so if anything happens, I'll hear it right away.

Good advice if you ask me.. besides that not a whole lot you can do

i honestly dont know why even put the sound system in
 
cops WILL pull over people from what ive seen for too loud of music
 
and do you really wanna make yourself death?

I would go with the gps tracker.  If not I would just find some how to make a custom bracket to secure that thing down
 

Buy some C4, connect it with some trip wire. If they pull it out, boom. For insurance if they see the trip wire, you can add a weight sensor under the sub. If the weight is decreased, instant detonation. I recommend about 10 pounds of C4 for maximum justice.

brunions

Gakusei

Buy some C4, connect it with some trip wire. If they pull it out, boom. For insurance if they see the trip wire, you can add a weight sensor under the sub. If the weight is decreased, instant detonation. I recommend about 10 pounds of C4 for maximum justice.

Except the both sensors could easily be set off by hitting bumps. A fix for this would be to use an RFID tag inside of the sub box that sends a signal to the C4 detonator once it goes out of range of the partner RFID tag in the car. By using this method, you can also save your car when the explosion happens

 
LOL well then if I had some super expensive high end 15s or 18s wouldn't it suck to get it stolen then? I'd rather not blow up my subs so I can have a chance of the cops recovering it later (if they cared... pigs...) xD

Just hang this on the outside of your car
 
 
 

ZachA

Just hang this on the outside of your car

 
I LOVE THIS ONE LOL!!!!!!!!!!!!

Install your subs in this and see if anyone tries to steal them...

MSIM, that video was a riot.  I loved it.