Originally posted by DDF
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I read this about the Dale 50W resistors... and was scratching my head myself, due to measurments of this family and others a few years back.
There was a thread much like this, a few years back, starting with a semi-troll (maybe not so semi) about how the Dayton "non-inductive" resistors were supposed to be a ripoff, since they cost more, and didn't have much lower inductance.
I had some examples, and at work a $3500 lab LCR meter, so I did some measurements. The Dayton standard resistors didn't have much inductance to speak of, the non-inductive ones had even less. Since we were talking tens of microhenries (.01 mH) you could say it ALL was too low to notice, (and so the higher price was unwarrented) AND yes there was a difference. (so they were lower in inductance, and as advertized) I didn't have single digit values of the Dale's, but ones in the 25, 50, 100 ohm range, and that should mean more turns and thereby more inductance. They were in the 10-50uH range, IIRC, also vanishingly small. I'd say that Phillip's meter might not do so well for such small measurments, but he then tests even lower values on the other resistors... Unless there's something weird with the 2 ohm value, I'd expect the Dale RH 50W series to be as low or lower and be an excellent choice.
The takeaway that I took away, was that most power resistors of small (<50 ohms) value are so low in inductance that special non-inductive windings aren't important. If you have a large value of thousands or tens of K ohms, then you will have a much larger inductance, and the counter wound resistors would make a difference.
I could pull the few values I have laying around and measure again, if anyone cares.
On the overall resistor/sound issue... I'm in the measuring camp, but have an open mind for possible effects I'm not aware of. I don't think there are many significant ones out there.
Probably the more important effect is, and perhaps reason to buy a "higher quality" part... is parts tolerance. If you have a 1% part vs a 10% part, say in the tweeter L-pad, and they are at their tolerance limits.. you could end up with a noticeable level difference between the two speakers. Or somewhere else, detuning a LCR notch, maybe causing a phase difference
by slightly altering the crossover tuning... and thereby degrading the overall sound or imaging... This goes for cap and inductor values too, of course.
Whether TC, or the effect of magnetic materials in the resistor construction, etc, have any perceveable effects... hard to imagine, but hey... someone come up with a test method and let's see if we can observe it...
And, listening can be a way to quickly hear large differences... but you should be able to hunt down and quantify the differences you hear.
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