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Speaker wire impedance? Speaker impedance?

I finally got into the owner’s manual for the speakers I bought last May (Revel M126Be) and under "SPEAKER CABLE" Revel is saying that, "High loop resistances that exceed 0.07 Ohms (for each wire run) will cause the loudspeaker’s filter network to be mis-terminated, resulting in considerable degradation of sound quality."

I ohmed out my (longer than I think is optimal) single run (the Revels are not bi-wireable) of (what I think I remember being) Kimber 8TC and I read 0.07. My B&Ws were shotgun bi-wired, so today I also doubled up my single runs with the other bi-wire cable (so two wires are terminating on one speaker post for + and - for both speakers) and rechecked the impedance and read 0.05 ohms which I assume is a variance going in the proper direction.

But I have a probably stupid and probably very basic question (as I make NO claims of having a tight grasp on this stuff). If a lower impedance run of speaker cable makes for an easier load for an amp to drive, why is it that a speaker with higher impedance is a easier load to drive? Can this be dumbed down for me?

I apologize because I am sure this has been asked before, but I cannot find the right combination of words for a search engine that is yielding an answer.

 

immatthewj
immatthewj OP
2,084 posts
 

@atmasphere and ​​​​​@carlsbad2 and @everybody else who tried to dumb this down an explain it for me--thank you.

@atmasphere and ​​​​​@carlsbad2 I now know that on a couple of levels I wouldn’t get an accurate reading--for one the meter I was using,

and also: the fact that I was taking my reading from the amplifier post (with cables hooked up) to speaker wire post of speaker (with cables hooked up, and then again from amp post to the other end with cables NOT hooked up on speaker end).

Either way, that probably screwed up the measurement I was TRYING to take, right?

So last question: the actual resistance was probably way lower that the 0.07 and 0.05 that I THOUGHT that I was reading?

And as an aside, my speaker cables (Kimber, and I THINK I remember that they they are 8TC and 4TC) probably are longer than what would be considered ideal.

 

 

 

carlsbad2's avatar
carlsbad2
1,637 posts
 

Your 8TC cables are 9AWG equivalent which is heavy enough for any run inside a listening room.  You have nothing to worry about.

Jerry

immatthewj OP
2,084 posts
 

Your 8TC cables are 9AWG equivalent which is heavy enough for any run inside a listening room.  You have nothing to worry about.

Okay, thanks for getting back to me on that, @carlsbad2  , the reason I mentioned it is because in one of my earlier configurations, in a larger room, I bought cables that were made up to be long enough that my year was not situated between speakers but on a side wall.  Therefore they are longer.  

atmasphere's avatar
atmasphere
11,844 posts
 

@immatthewj As a general rule of thumb, no matter what speaker cable you have, its good practice to keep it as short as possible. This is why monoblock amplifiers are common in high end audio as it allows the shortest cable length possible.

If the cable was connected to an amplifier and speaker, the reading you got isn't representative of anything. That's a pretty good meter that can read 0.05 Ohms BTW!

immatthewj OP
2,084 posts
 

@atmasphere , after I read the replies I started thinking that the fact that I had always had at least the amp end of my cables connected when I was trying to measure made my readings to not be valid.

I would think that regardless of the length of the cable, the actual resistance was lower than what I thought I was reading?

As far as the meter, I didn't think it was anything special--when my old Radioshack meter that I used to bias my amp, I bought a Southwire at Lowes and that's what I was using.  

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