Car audio experts, fuse and wire guage?

[scottmandue]

So I have settled on installing a Soundstream RUB2.450 130 x 2 power amp.

They recommend 4 guage power wire... is that correct?

It comes with two 25A fuses built in, should I add a fuse to the hot wire? What Ampere rating fuse?

Thanks,

Scott

[RWebb]

4 is huge

how long is the run?

good practice to fuse all wires as near the origination with the battery as possible

[masraum]

Originally Posted by NotaBRG

Total RMS Wattage x 2 (Inverse of Amp Efficiency) ÷ 13.8 Volts = Current Draw in Amperes

You just totally made that up, didn't you?

j/k

[greglepore]

Wire gauge aside, if you for some reason short he powercable on the battery side of the amp, its unprotected by the amp fuse, so yes, it must be fused at the battery.

[scottmandue]

Originally Posted by NotaBRG

I assume he's putting the amp in the trunk of the Miata, so the run will be a foot or two.

Yes, I am figuring three feet max.

Amazon has the fuse holders with 100 amp fuses that I'm pretty sure is WAY too high of a rating, using the formula all I should need is 20A. I don't want a fire hazard but I don't want to be popping the trunk to change fuses all the time either.

[imcarthur]

Follow the lead of the amplifier & use 25A inline fuses. Too large a fuse is useless. 4 gauge seems overkill as well but follow the recommendations in the users manual.

Ian

[RANDY P]

4GA? for that amp?! You'll spend almost as much on wiring and bull **** as you will on the amp.

Point of reference: My old-skool Punch150HD has 10GA INPUT WIRE- it puts out almost 400WRMS and is inefficient compared to a new amp...

3 FT run I'd do 10GA and a waterproof blade fuse. Get that at the auto parts store. DONE!

10 GA you'll be just fine.

rjp

[RANDY P]

Oh and deadly important, install a fuse (like I said, waterproof blade in 10GA) within 6 inches of the battery terminal.

Ground wire, reasonably as short as possible n same GA as input wire.

[Gogar]

4GA is bling and is the recommendation of the people who sell 4GA wire. 10 will be great.

[rusnak]

I spent as much on cables and fuses as on one of my 3 Soundstream amps. Everything is hidden and sounds pretty fantastic.

[RANDY P]

Dood u need welding cable

[rusnak]

Well I did have one of the amps set itself on fire and burn up completely.

[imcarthur]

Here is a simplified chart: Recommended Power and Ground Cable Sizes & Speaker Wire Size and Length

So for a bit of safety margin, use 8 gauge & fuse at 25A. It would appear that your amp has lugs that will accept 4 gauge but that doesn't mean it is necessary.

Ian