Whats the deal with non inductive ww resistors?

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OK, now I'm experience enough in the field of audio to know that things don't always sound like they measure, nor do the measure like they sound...

With that in mind, I recently received some Mills non-inductive wire wound resistors. Out of curiosity, I compared their inductance to standard sand-cast white rectangular wire wound resistors that I got from Radio Shack for a fraction of the price. The result is that BOTH have EXACTLY THE SAME inductance (3.4 uH):headbash: What gives? Are the ones from Radio Shack secretly non-inductive, or are the ones from Mills really NOT non-inductive?

Just seemed sorta strange to me :(
 
Non-inductive ww restors doesn't exist but bifilar (bifilärt in swedish, not sure the english word) wounded resistors have less inductance than a regaular one wich is a coil. If you are after power resistors with good HF-properties, check the one from Caddock, very expensive but also really good.

BTW: 3.4 µH is rather much. Compare with a regular coil in a output filter for power amps. 10 mm diam and 15-20 turns = 0,5-1 µH.

If you shall use the resistors as emitter resistances you should have as low inductance as possible.
 
I am planning to use these resistors on the emitters of my a40 amp.

Joe: I suppose the leads could have contributed to the inductance - they are 3 inches long, but I used the leads when measuring both types of resistors, so the additive inductance would be the same in both cases.

I had just assumed the Mills 5w resistors would be very different from the Radio Shack ones and was surprised to find no difference in measurement.
 
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