Why do speakers and amps use ohms ratings?

So you can correctly match the impedance's when rigging the systems up. An ohm is a measurement of resistance. "Ohms is a measure of resistance. You don't think of it, but substances conduct or resist electricity on a scale. Rubber isn't very conductive, copper is...

"When the electricity passes into the speaker, some of it is 'resisted.' The ohms rating of the speaker is how much is resisted, and an indication of how much energy it takes to drive it - the higher the ohms rating, the more difficult it is to drive.

"An amplifier amplifies the electricial signal, causing the speaker to vibrate with greater force, otherwise the impulse would be barely audible. How much the amp drives is measured in watts. When an amp manufacturer gives it's wattage rating, it's always at a specific Ohm resistance. 100 watts @ 4 ohms, for example. When the resistance is 4 ohms, this amp will produce 100 watts. If that resistance changes, the amp will produce a different amount of watts."

Basically, you will want to match the ohms ratings of the speakers and the amplifiers to get the most efficient combination. You will not get a better match by using an 8 ohm amp and 2 ohm speakers... you just run a better chance of blowing out the speakers. You're best off matching 8 with 8, 4 with 4, etc.

Some manufacturers make speakers at 6 ohms to bridge the gap between 4 and 8 ohm amps... these will work with both without much issue or without you being aware of any problems, but technically not at the highest efficiency. amps use ohms ratings to 1) provide flexibility in installations 2) provide a "load" for the amplifier circuitry and 3) to protect the circuitry from loads that draw too much current. current (amps) is a fucntion of resistance (ohms) and voltage (potential). current = voltage divided by resistance. the amplifier puts alternating voltage to the terminals, and that value depends upon the sound frequency and intensity. if your speakers have too much resistance, very little current will flow through the voice coil. it might not be enough to move the cone if it's too high! if your speakers have too little resistance, they will draw more current than the amplifier is designed to handle and you will damage the output transformers and/or your speakers. power is also related to resistance. power(watts) = volts squared divided by resistance. by that, you can see that a lower load results in greater power output. keep your speakers in the design range of your amp and you can't go wrong, but generally the lower the better. It's a way to decide whether an amp

and speaker will work together or not.

See the information from the links below.

_

_

_

_

_

The answers post by the user, for information only, CeQnA.com does not guarantee the right.