I'm thinking of replacing my current speakers and amping them (65x4). Is it really necessary to rewire the fronts? At what point is the added trouble worth it (I'm assuming its not goint to be that easy from what I've read)? This won't be a competition vehicle I just want it to sound good and I have a hard time understanding how a larger speaker wire is going to make that much of a difference.

 

IMHO, it depends on how much power your pushing.
I'm running 50w speakers, use factory wiring thru the door connectors, then splice into the harness. Haven't noticed any degradation of sound, and the wires haven't melted yet.

In a pure DC circuit (audio is close enough):
Power = (Current)² x DC resistance.

With wire, you're interested in the resistance of the wire and the amount of current it can handle, which is determined by its guage.

So plugging some numbers in:
50 Watt Speakers = (Current)² x 4 ohms
50 watts / 4 ohmes = 12.5 = (Current)² , therefore
Current = sq rt of 12.5 = or 3.5 amps

The factory wiring can handle this without concern.

 

thanks..that should make it much easier to wire in new speakers. Is there a rule of thumb for how much amperage drawn vs. gauge of wire?

 

http://www.crutchfield.com/installgu...ble_gauge.html

If you can work out the amperage of the power being sent through, this chart will work nicely

 

Hey grutter I hate to tell ya but, the power coming out of an amp and going into a speaker is not dc current , it is def. ac current.

 

You're absolutely correct. But the formulas for calculating AC are more complex. Additionally, you can't really use the DC resistance of the speaker, it should be impedance. And the amp power is rated RMS, but the circuits need to be designed to handle peak. And AC calculations are based on sinusoidal waveforms, but audio is non-sinusoidal (unless your idea of music is test-tones). So what I offered was a basic formula that will provide relatively accurate results for a single phase AC circuit.


BTW, the Crutchfield table that bastard <no disrespect intended> refererenced is for power wiring, not speakers. It looked pretty crude to me.

Here is a better wire guage table that hopefully will help someone out. The table below is based on the cross-sectional area of the wiring and its corresponding ampacity, or ability to carry current.

AWG Max Current (Amps)
0 150
4 85
8 45
10 30
12 20
14 15
16 10
18 8

 

Hey just so you know i wasnt trying to flame you just didnt want wrong info being passed , but i understand what your saying now. It's alllll good !! ( ford focus commercial )

 

lol btw should i run 0 awg wire for my 150 watt speakers ? lol