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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 2 responses by gdnrbob

gdnrbob
4,417 posts
 
And, remember most of the amps power is going to the lower frequencies. So, if the impedance dips at low frequecies, your amp will have a hard time keeping up with the demands of the speaker.
Like the water in the hose instead of being restricted by a nozzle, is now having to provide the same pressure in a larger diameter hose.
HTH
Bob
gdnrbob
4,417 posts
 
 If the former, than some of the lower impedance speakers and higher power transistor amps will be of interest; if the former, then you will be very careful to be matching the speaker to the amplifier (and not the other way ’round) and most likely avoiding lower impedances in general. 
 Ralph, you mentioned 'former' twice in the last part of your post.
Bob

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