A 600W RMS car amplifier normally calls for 4 AWG copper power and ground wire, with a main fuse sized to the cable’s rating, not the amp’s wattage.
For the full breakdown, see our best 600 Watt Amp guide.
A 600W amp fed by 8-gauge wire will heat that cable long before the bass hits, because the fuse and the wire — not the amp’s box — decide whether the run survives. Sorting out what gauge wire for a 600 watt amp actually needs comes down to two numbers: how much current the amplifier draws, and how much current the cable is rated to carry. Miss either and the cheapest part in the system turns into the most expensive one.
How Do You Pick Wire Gauge For A 600 Watt Amp?
For a 600W RMS amplifier, 4 AWG copper is the standard pick. That gauge covers the 500–1000W RMS band, and it’s what most installers reach for on a 600-watt build. Smaller systems under 500W RMS can run 8 AWG, and anything past 1000W RMS steps up to 2 AWG or 1/0 AWG.
Current draw is the number the gauge has to survive. A 600W RMS amp is commonly treated as roughly 50 amps on a 12-volt system, but the real figure shifts with amplifier class, efficiency, and charging voltage. A Class D amp at 14.4 volts pulls less than a Class AB amp at 12.6, which is one reason installers size wire generously instead of exactly.
Run length counts as well. Resistance climbs with distance, so a long cable to a trunk-mounted amp may justify stepping up a size even at the same power level. Wire material and brand ratings vary too —