I just bought an Infinity Class D mono amp that will do 850 watts RMS @ 4ohm and an Infinity Kappa Perfect DVC 12" that can handle 400 watts RMS. Now, at the moment, I only have one of these subs because the other one is on backorder until Feb. When I get both i am going to wire them up so that the pull 4ohm on the amp and everything will be perfect. But, until Febuary, should I just wire the 1 sub up at 2ohm and leave the gain way down or wire it up at 8ohm and not worry about it? I have head that 8ohm will hurt the amp but I am afariad that 2ohm power will pop the sub. What should I do?
Temporary Solution
- Thread starter Fawks
- Start date
Wiring the sub as a 2 ohm load will hurt the amp if it's not specifically labeled "2-ohm stable."
Wiring the sub as an 8-ohm load will reduce the power to a level the sub can safely handle.
Eric
Wiring the sub as an 8-ohm load will reduce the power to a level the sub can safely handle.
Eric
Your amp puts out 850 @ 4 ohm, and your sub can handle 400...right? And it is a dual 4 ohm sub?
If that is the case, I would definately wire it up to 8 ohm. This will not hurt the amp one bit, and should throttle back the power to give the sub about it's max RMS. I will give you a 99.999% guarantee that wiring that amp at 8 ohm will not hurt it. You could wire four 8 ohm subs to it at a 32 ohm load and not hurt it...you just would not get much power at all out of it. The problem with impedance comes with showing the amp too low of a load. Since the impedance is a measure of the resistance to the flow of current through the amp, if you drop it lower than the amp is designed to handle then you get more current flowing through the circuit than it can handle and things get too hot. The heat and current flow are what will damage the amp, not the lack of it that would result from higher ohm loads.
As an example...if you took a 2AWG fused wire from the battery to say, a 2000 watt capable amp, and grounded that amp with say, an 18AWG wire, then hooked the amp up to a load that should draw max power from the amp...you are likely to catch the 18AWG ground on fire. The fuse in the 2AWG wire will not blow if it is the proper size for the amp, and the sheathing on the 2AWG wire probably won't even get warm at all...but that 18AWG wire was not designed for that amount of current, and nobody fuses a ground, so what happens is thermal failure of the wire. This is pretty much the same thing that happens to the internals of an amp (circuit traces, components, wires, etc...) when you surpass the amps ability to handle the flow of current.
If that is the case, I would definately wire it up to 8 ohm. This will not hurt the amp one bit, and should throttle back the power to give the sub about it's max RMS. I will give you a 99.999% guarantee that wiring that amp at 8 ohm will not hurt it. You could wire four 8 ohm subs to it at a 32 ohm load and not hurt it...you just would not get much power at all out of it. The problem with impedance comes with showing the amp too low of a load. Since the impedance is a measure of the resistance to the flow of current through the amp, if you drop it lower than the amp is designed to handle then you get more current flowing through the circuit than it can handle and things get too hot. The heat and current flow are what will damage the amp, not the lack of it that would result from higher ohm loads.
As an example...if you took a 2AWG fused wire from the battery to say, a 2000 watt capable amp, and grounded that amp with say, an 18AWG wire, then hooked the amp up to a load that should draw max power from the amp...you are likely to catch the 18AWG ground on fire. The fuse in the 2AWG wire will not blow if it is the proper size for the amp, and the sheathing on the 2AWG wire probably won't even get warm at all...but that 18AWG wire was not designed for that amount of current, and nobody fuses a ground, so what happens is thermal failure of the wire. This is pretty much the same thing that happens to the internals of an amp (circuit traces, components, wires, etc...) when you surpass the amps ability to handle the flow of current.