[quote]Originally posted by Philizdaman:<br /><strong>ok ive been reading a lot on car audio systems but im still kinda in the dark. Can someone explain hz and khz to me and ohms, and rms i think i understand them just it would help for someone to explain them in english without using the huge tech words also how do i know if a amp can handle a speaker(like what do i look for)<br />thx</strong><hr></blockquote>

Okay let's see. Hz is short for hertz which is a numerical expression of the frequency cycle of the tone. Now that I have confused you more <img src="smile.gif" border="0"> Let me break it down for you. Imagine you are looking at a pond. And you threw a rock in the pond. When the rock hit the water it makes a splash. But there is a ripple sent across the water surface. This is the same way sound travels in waves. With me still <img src="smile.gif" border="0"> Each wave is a cycle. So the term Hz or hertz is just a measure of these cycles per second. So let's use the pond reference once again to help out. When you threw the rock in the water it made the ripples or waves. Looking at the waves there is a dip then a peak then a dip and peak and so on. A cycle is measured from the bottom of a dip to the bottom of the next dip. In the middle there is a peak. This is what is known as a cycle. Still with me I hope <img src="smile.gif" border="0"> So all the term hz or hertz is. Is a measure of the number of these cycles that occur in one second. For example 1hz would be 1 cycle per second, 2hz would be 2 cycles per second and so on.

Khz or Kilohertz is the same thing to hz or hertz. As a kilometer is to a meter. It's a thousand of them. So 2khz or 2kilohertz would be 2000 cycles per second. Did I lose you yet <img src="smile.gif" border="0"> hope not.

Okay ohms is an electrical measurement of resistance. This may take a little longer to explain <img src="smile.gif" border="0"> But here goes. I will have to explain the three basic principals of electricity. The three most basic units in electricity are voltage (V), current (I) and resistance (r). Voltage is measured in volts, current is measured in amps and resistance is measured in ohms. <br />A neat analogy to help understand these terms is a system of plumbing pipes. The voltage is equivalent to the water pressure, the current is equivalent to the flow rate, and the resistance is like the pipe size.

There is a basic equation in electrical engineering that states how the three terms relate. It says that the current is equal to the voltage divided by the resistance.

I = V/r

Let's see how this relation applies to the plumbing system. Let's say you have a tank of pressurized water connected to a hose that you are using to water the garden.

What happens if you increase the pressure in the tank? You probably can guess that this makes more water come out of the hose. The same is true of an electrical system: Increasing the voltage will make more current flow.

Let's say you increase the diameter of the hose and all of the fittings to the tank. You probably guessed that this also makes more water come out of the hose. This is like decreasing the resistance in an electrical system, which increases the current flow.

Electrical power is measured in watts. In an electrical system power (P) is equal to the voltage multiplied by the current.

<br />P = VI<br />The water analogy still applies. Take a hose and point it at a waterwheel like the ones that were used to turn grinding stones in watermills. You can increase the power generated by the waterwheel in two ways. If you increase the pressure of the water coming out of the hose, it hits the waterwheel with a lot more force and the wheel turns faster, generating more power. If you increase the flow rate, the waterwheel turns faster because of the weight of the extra water hitting it.

In an electrical system, increasing either the current or the voltage will result in higher power. Let's say you have a system with a 6-volt light bulb hooked up to a 6-volt battery. The power output of the light bulb is 100 watts. Using the equation above, we can calculate how much current in amps would be required to get 100 watts out of this 6-volt bulb.

You know that P = 100 W, and V = 6 V. So you can rearrange the equation to solve for I and substitute in the numbers.

<br />I = P/V = 100 W / 6 V = 16.66 amps<br />What would happen if you use a 12-volt battery and a 12-volt light bulb to get 100 watts of power?

<br />100 W / 12 V = 8.33 amps<br />So this system produces the same power, but with half the current. There is an advantage that comes from using less current to make the same amount of power. The resistance in electrical wires consumes power, and the power consumed increases as the current going through the wires increases. You can see how this happens by doing a little rearranging of the two equations. What you need is an equation for power in terms of resistance and current. Let's rearrange the first equation:

<br />I = V / R can be restated as V = I R<br />Now you can substitute the equation for V into the other equation:

<br />P = V I substituting for V we get P = IR I, or P = I2R<br />What this equation tells you is that the power consumed by the wires increases if the resistance of the wires increases (for instance, if the wires get smaller or are made of a less conductive material). But it increases dramatically if the current going through the wires increases. So using a higher voltage to reduce the current can make electrical systems more efficient. The efficiency of electric motors also improves at higher voltages. still with me <img src="smile.gif" border="0">

RMS is "the root mean Square" which basically means an average of the power a speaker can handle. As far as an amp handling a speaker. Make sure the ohm load can be handled by the amp. Let's take a Rockford Fosgate BD1000.1 as an example. It is rated to put out 500w RMS at 4ohms That means at 4ohms itwill put out an average of 500w some times less some times more. Depending upon the music signal from the source unit (cd player). Look at the rms ratings and the impedence ( measured in ohms) ratings of the speakers. If the speaker can handle the power, and the speaker provides the impedence the amp is rated for. You have a good match. Did I miss anythng. I feel like I just wrote a book <img src="biggrin.gif" border="0"> If I confused you in any way. Just post and I will try to help clear it up.

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