How many watts rms is 4 gauge wire good for generally?

[SpeedEuphoria 10+ year member]

Roughly how many watts is 4 gauge good for with ~17ft length?

Click to read more...

 

[hispls 5,000+ posts]

No real rule of thumb on this. You can find ampacity charts out there, but they're mostly for 50' and up runs. The shorter your run the smaller wire you can get away with. I'd say go as big as you can afford and from my own experience 4 guage is adequate for say a 200X2 amp on your fronts and 1000 to 1200W class D amp on your sub(s)

 

[SpeedEuphoria 10+ year member]

Thanks I did see some charts, like this

They state the RMS or Amps with 50% efficiency.

I have no idea what the efficiency of most class D amps is currently and have not seen specs for any.

I'm looking to power subs only at this point and was looking at up to ~1500w, so 16' of 4 gauge should be OK I take it?

 

[SPLaudio 5,000+ posts]

17' of good 4g wire you can pull 120amps thru without out voltage loss. i wouldnt run anything more than 1 1500rms amp class d amp on 4g.

 

[SpeedEuphoria 10+ year member]

thanks thats all I needed to know as I'm familiar with the V x A=Watts formula