I have an old pair of RadioShack inductors part # 40-1326 . This
4.25 mh inductor uses about 340 G of #17 magnet wire on a .8"
core with a length of .8" which is almost exactly I get when I try
to calculate a 4.25 MH inductor using a .8" diameter coil form with
a length of .8" using #17 gage wire ( well it's listed as 1.1mm ) .
But the RadioShack coil has some ferrite material making up about
1/3 of the center of the coil. Why in the world would they do that as
when I ran the figures it can't be influencing the inductance much.
Could that small amount of ferrite degrade the audio much if any
compared to a pure air core coil when used in a crossover ?
4.25 mh inductor uses about 340 G of #17 magnet wire on a .8"
core with a length of .8" which is almost exactly I get when I try
to calculate a 4.25 MH inductor using a .8" diameter coil form with
a length of .8" using #17 gage wire ( well it's listed as 1.1mm ) .
But the RadioShack coil has some ferrite material making up about
1/3 of the center of the coil. Why in the world would they do that as
when I ran the figures it can't be influencing the inductance much.
Could that small amount of ferrite degrade the audio much if any
compared to a pure air core coil when used in a crossover ?