Adding a Amp

[jdc753 10+ year member]

Background: what I have is 4 Infinity 5.25" speakers said to handle 45w RMS and 2 Infinity 12" subs 4ohm SVC said to handle 300w RMS. These are being powerd off the headunit for the speakers and the subs from a Jensen 4 channel amp feeding them a claimed 150w each. The amp is wired with 4awg from a cheap Scosche made Wally world kit, 40amp blade style fuse.

Planned: I would like to add an amp most likely this http://www.crutchfield.com/S-yYpu2I0fmaI/cgi-bin/ProdView.asp?g=120&I=489AP2000

Or something comparable I can get my hands on for cheap //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif and then swap my Jensen amp onto the door speakers giving them 50 watts each RMS.

Question: I have extra 4gauge laying around and I would like to do this with buying as few things as possible. However I'm sure I will need to upgrade the fuse and fuseholder but What size fuse should I run? Should it be 100amp to match the fuses in the Profile amp, or should it be a combination of the 2 amps fuses, 140amp? I know its not a big system compared to what everyone else seems to be running but will I need to upgrade to 1/0 guage or will the 4 guage handle this? I guess I could always make 2 runs of 4 gauge too, if that would be recommended versus putting the entire load on one run.

Looking for suggestions and maybe a lead on a cheap 300x2 @4ohm amp //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

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[Boulderguy 10+ year member]

Up to about 1200w RMS & 15' you're fine with 4g cable, tho 2g would be better after 1000w, but not a big difference. Fuse the wire at 140a. You can always add a second run of 4g should you upgrade.

 

[jdc753 10+ year member]

Thanks for the reply, I will have to look if I have enough 4g to make 2 runs, seems to be the easiest/cheapest way of doing it, and I would feel better knowing that much current wasn't going down one wire. The run is over 15' but under 20' Now to just get the components and get creative with my install.

 

[Boulderguy 10+ year member]

Not sure I was clear before - the single 4g should be fine for what I'm reading in your setup. Unless you're going for serious SPL or driving the system really hard frequently there's no gain to adding a second 4g - yet.

Start adding amps later? Then do the second 4g.

 

[jdc753 10+ year member]

ok. Makes sense, I will probably pick up a cheap distrobution block then to accept 4g and have 2 4g outputs, along with the fuse holder and fuse. Its definitly not going to be a major SPL system 2 12's that only take 300rms would get laughed at I would think, especially in a sealed box. So far they pound pretty good off 150w though, looking foward to feeding them 300w each.

 

[Boulderguy 10+ year member]

If you put the D-block close to the amps - like within 24" - you're fine using 8g from there.