Sub/amp/electrical questions
bhw33191
09-05-2008, 11:00 AM
I don't hav emuch time to type this so bare with me. I'm going to get a new amp and sub for my car. I was just wondering what an ohm is? I heard you have to pay attention to these or else you risk damageing amp/sub.
silicon212
09-05-2008, 12:55 PM
An ohm is a unit of measure - it's used to measure DC resistance and AC impedance, which are not the same thing.
Ohm's Law is used to determine current requirements (and therefore wire gauge) for a particular circuit.
DC measures straight resistance, where the AC measurement is not only of resistance, but inductance as well (an inductor impedes the flow of AC electricity, the voice coil in a speaker is an inductor).
Therefore, when it comes to audio, the ohm is used to measure AC impedance, as audio frequency energy is a form of AC electricity.
On an audio system of high wattage (high being anything more than factory), it is imperative and critical that your speakers match the impedance requirement of your amplifier, or the amplifier could fail. Likewise, if the impedance of the speaker is too high for the output of the amplifier, the speaker could fail.
Ohm's Law is used to determine current requirements (and therefore wire gauge) for a particular circuit.
DC measures straight resistance, where the AC measurement is not only of resistance, but inductance as well (an inductor impedes the flow of AC electricity, the voice coil in a speaker is an inductor).
Therefore, when it comes to audio, the ohm is used to measure AC impedance, as audio frequency energy is a form of AC electricity.
On an audio system of high wattage (high being anything more than factory), it is imperative and critical that your speakers match the impedance requirement of your amplifier, or the amplifier could fail. Likewise, if the impedance of the speaker is too high for the output of the amplifier, the speaker could fail.
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