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Why are low impedance speakers harder to drive than high impedance speakers

I don't understand the electrical reason for this. I look at it from a mechanical point of view. If I have a spring that is of less resistance, and push it with my hand, it takes little effort, and I am not working hard to push it. When I have a stiffer spring (higher resistance)  I have to work harder to push it. This is inversely proportional when we are looking at amplifier/speaker values.

So, when I look at a speaker with an 8 ohm rating, it is easier to drive than a speaker with a 4 ohm load. This does not make sense to me, although I know it to be true. I have yet been able to have it explained to me that makes it clear.  Can someone explain this to me in a manner that does not require an EE degree?

Thanks

128x128crazyeddy

Showing 1 response by kfirbar

kfirbar
1 posts
 
Hi all, 
This is my first post in this forum :)

According to Al's information, having the two extreme examples, 
I have the exact opposite question: 
For headphones, why do we need good, high, powered amp to 
move headphones with very high impedance (300-600 ohms). 
According to the ohm equasion, for the same power, as long as the amplifier "understand" that the output is not disconnected (as the "100,000 ohms" al's example), than the amp needs only a tiny current to "drive" the headphones.
What am I missing here? 

Thank you all!
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