As you all know, some JBL inductors have rather large DCR values. JBL was careful to factor the DCR into the network design, so substituting high quality, low DCR, air core inductors can have disastrous effects. For example, Giskard wrote, “…the 3.5mH air core inductor often used across the LE5’s is very tiny and has a DCR of 7.5 ohms…” “Rich” wrote “The 1.8mH iron-core inductors that JBL used the 4350 monitor’s N-3107 network, to crossover from the 2202 mid-bass to the 2440 midrange drivers, each have a DCR of 3.5 ohms.” Giskard wrote, “[The 3124’s L1s] are little 1.0mH air core inductors wound on plastic square bobbins and they have a DCR of 7.5 ohms.”
My immediate concern is purchasing inductors for a 4344 MKII network that I’m building. The schematic calls out iron core inductors and I need to know if I can use low-DCR air core inductors instead.