How is headphone impedance ( DC ) created ? That is... is it due to the co= pper coil resistance or is additional resistance added via more resistive m= aterials or discrete resistors ? I am not asking about AC impedance. Gus =20 --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .