# Building a new system...have some questions **URL:** https://forums.speedlife.net/t/building-a-new-system-have-some-questions/241394 **Category:** Shift518 Automotive **Created:** [January 15, 2009, 5:47pm UTC](https://forums.speedlife.net/t/building-a-new-system-have-some-questions/241394 "2009-01-15T17:47:29Z") **Posts on this page:** 1 **Showing post:** 61
### Author: ![Auto0utcast](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/auto0utcast/32/6281_2.png) [@Auto0utcast](https://forums.speedlife.net/u/Auto0utcast) #### Post date: [January 22, 2009, 2:36pm UTC](https://forums.speedlife.net/t/building-a-new-system-have-some-questions/241394/61 "2009-01-22T14:36:34Z")
> [@Drug Addicts](https://forums.speedlife.net/t/drug-addicts/12891/2): > > How do you isolate a capacitor to one amp that is being powered by the vehicles common electrical system? > > (and yes, I know it could be done in a competition vehicle-talking daily drivers here) 0/1 gauge power wire off battery to distro block… split to two 4 gauge wires… one 4 gauge wire goes directly to interior speaker amp… other 4 gauge wire goes to capacitor, capacitor gets grounded. run 4 gauge wire from capacitor to subwoofer amp… then ground subwoofer amp. i ALWAYS used separate grounds for separate amps in my vehicles…might be more time taking and a pain in the ass to do but when done PROPERLY, a shorter, thicker, isolated ground will prove to be better than a shared common ground. ive had PLENTY of systems in my cars… the most radical of which was (4) 12" jl w3’s powered off a 1000/1, a jl A4300 4 channel interior amp powering a set of MA Audio HK-68 speakers off a alpine head unit… i ran all the wiring, installed all the speakers, and tuned the amps myself. and yes… i had a 2 farad MA Audio digital capacitor in there as well…isolated to the sub amp of course. --- _[View the full topic](https://forums.speedlife.net/t/building-a-new-system-have-some-questions/241394)._