What do I need for RMS wattage on a an amp if i am wiring my subs in parallel?

Question

I plan on putting two 300 watt RMS subs in a car. I am going to wire the subs in parallel to a one channel amp. Should I buy a 300 watt RMS one channel amp or a 600 watt RMS one channel amp for my subs?

Answer 1

You need 600w rms amp. For impedance this is the math. If you connect your speakers in series , just add the total is your total impedance, example: two 2ohms in series is a 4ohms load. If you have dual coil subs, each coil counts for it's own impoedance, for instance, a dual 4ohms coil sub, if the coils are connected in series this load will be 8hms, but if in parallel the sub's total impedance is 2ohms. When you connect two subs in parallel just devide by half (this is the easiest way to come up with the total but, this math only works if not pass 8ohms, anyhting over that you have to use the formula). The general formula for parallel is: 1/Rt = 1/R1 + 1/R2 + 1/R3 ... R stands for resistance, load measured in ohms.

Answer 2

The power will be split between the subs, so if you want to run the maximum power to the subwoofers you need a 600-watt amp.

Be sure to figure out your subwoofers' total impedance so you know which power rating to look for. Most mono amps have different power ratings for 4-ohm vs. 2-ohm loads.

Answer 3

Regardles how subs are wired, you ALWAYS add the total watts RMS of both subs (or all).

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