Greetings All,
I'm finally building a set of surround sound speakers for the house. I'm currently working on fabricating the cross overs for the midrange drivers.
The question is, how would you measure if an iron cored inductor is going to saturate and cause a problem?
The golden rule for 'audiophiles' is air cored inductors only in the signal path, but I need 5x 0.6mH inductors and that turns out to be ALOT of magnet wire. (approx 270 feet of 20 gauge wire for 5 air cored inductors.)
Being a pack rat, I've salvaged a bunch of toroidal cores out of scrape 360watt SMPS. The cores were originally used as inductors on the line input section. I've test wound one of these cores with ~8 feet of 20ga wire, and achieved my goal of 0.6mH. Here's a picture of a bare core and my home made inductor if it helps:
At the moment, I am at the decision point of deciding between abiding by the 'audiophile law' or just using the iron cored inductor.
If it helps, this inductor will be used as part of a Butterworth 3rd order low pass filter, with a crossover frequency of 3Khz, driving an
8 ohm midrange speaker at no more than 50 watts rms.Also, I can measure the impediance vs frequency over the audio range, can I test the iron cored inductor at various amplitudes settings and get an idea on the likely hood of core saturation becoming a problem?
Thanks in advance,
Take Care, James Lerch