Just added a sub to my setup and no surprise i just blew the fuse in the mainline. i have a jl 300/2 and i just added a jl 500/1 , as well as a cdt component system and a 12w7.....how big of a fuse do i need?

 

To get the minimum fuse size take all the fuses on the two amps, and add them together, and probably add an extra 10%. However, the fuse by the battery should be in contrast to the wire size, imo. I know other people will say to fuse according to your equipment, but I've never had a problem running a much bigger fuse in comparison to my amp.

 

You use the recommended fuse size according to your main power wire size/gauge. (www.bcae1.com). This is what will limit/determine what fuse(s) you can run. Ex: if you have a 4 awg main power wire, a 125A fuse is the maximum recommended fuse. If you have 0 awg, you're good up to near 325A, or anything less than that. This is to protect your car and you. If your amps don't have onboard fuses (like my Clarion, which has an internal breaker -type), just fuse accordingly with a fused distro block or inline fuse, according to wire gauge (the specs on the DPX1001.1 say 130A max draw, but I'm only using a 100A fuse, as I doubt I'll ever pull that much). If you're ever in doubt, drop by a reputable local shop. Cheers.