Wire Guide

[chevyaudio]

Keep in mind that length is a factor here as well. If you're doing a long run (>20 feet), you should use one size larger. It doesn't hurt to use a wire size that's larger than necessary, but it will usually cost more and can be more difficult to install.

Power Wire:

10 gauge: ~35 amperes
Class D (~70% efficiency) - <350 watts
Class A/B (~50% efficiency) - <250 watts

8 gauge: ~55 amperes
Class D (~70% efficiency) - <550 watts
Class A/B (~50% efficiency) - <400 watts

6 gauge: ~87 amperes
Class D (~70% efficiency) - <875 watts
Class A/B (~50% efficiency) - <625 watts

4 gauge: ~140 amperes
Class D (~70% efficiency) - <1400 watts
Class A/B (~50% efficiency) - <1000 watts

2 gauge: ~220 amperes
Class D (~70% efficiency) - <2200 watts
Class A/B (~50% efficiency) - <1500 watts

1/0 gauge: ~350 amperes
Class D (~70% efficiency) - <3500 watts
Class A/B (~50% efficiency) - <2500 watts

2/0 gauge: ~440 amperes
Class D (~70% efficiency) - <4400 watts
Class A/B (~50% efficiency) - <3000 watts

4/0 gauge: ~700 amperes
Class D (~70% efficiency) - <7000 watts
Class A/B (~50% efficiency) - <5000 watts

Speaker wire:

22 gauge: ~2.2 amperes
8 ohms - <36 watts
6 ohms - <27 watts
4 ohms - <18 watts
3 ohms - <13.5 watts
2 ohms - <9 watts
1 ohm - <4.5 watts

20 gauge: ~3.4 amperes
8 ohms - <96 watts
6 ohms - <72 watts
4 ohms - <48 watts
3 ohms - <36 watts
2 ohms - <24 watts
1 ohm - <12 watts

18 gauge: ~5.5 amperes
8 ohms - <240 watts
6 ohms - <180 watts
4 ohms - <120 watts
3 ohms - <90 watts
2 ohms - <60 watts
1 ohm - <30 watts

16 gauge: ~8.7 amperes
8 ohms - <600 watts
6 ohms - <450 watts
4 ohms - <300 watts
3 ohms - <225 watts
2 ohms - <150 watts
1 ohm - <75 watts

14 gauge: ~13.7 amperes
8 ohms - <1500 watts
6 ohms - <1125 watts
4 ohms - <750 watts
3 ohms - <563 watts
2 ohms - <375 watts
1 ohm - <188 watts

12 gauge: ~21.8 amperes
8 ohms - <3800 watts
6 ohms - <2850 watts
4 ohms - <1900 watts
3 ohms - <1425 watts
2 ohms - <950 watts
1 ohm - <475 watts

10 gauge: ~34.6 amperes
8 ohms - <9600 watts
6 ohms - <7200 watts
4 ohms - <4800 watts
3 ohms - <3600 watts
2 ohms - <2400 watts
1 ohm - <1200 watts

8 gauge: ~55 amperes
8 ohms - <24000 watts
6 ohms - <18000 watts
4 ohms - <12000 watts
3 ohms - <9000 watts
2 ohms - <6000 watts
1 ohm - <3000 watts

Thanks to Jmac