Support Forums › Forums › FIR Designer M Support › DFM Question › Reply To: DFM Question
I’ve contacted DFM asking for the IIR parameters. Please let me know which information you need in detail.
Thanks. See the section “Branded IIR Filter Emulation” on
Regarding the Multiway FIR I have some questions:
– We mainly use multi-way speakers with active processing (no passive crossovers). So, I want to know the differences (advantages and disadvantages) between making the X-OVER using IIR HPF and LPF and enventually All-Pass filter for Phase slope correction, and then use a FIR in the input to flattern the phase from around 400Hz and above – and using FIR on each way instead of IIR.
If both approaches result in the same transfer function, and you have the processing flexibility available, then there is no advantage of one method over the other method. However, doing crossovers and phase unwrapping all in FIR usually requires longer FIR filters, than doing a mixed IIR+FIR approach, and the maximum available FIR filter lengths in your processor might not be long enough. So mixed IIR+FIR might be the most viable for you.
Also with FIR, even though the software can calculate very fine and high-Q correction filters, we suggest taking care not to correct specifically for one measurement at one level. To help, we provide measurement averaging – the last tab in the workflow. You can use this to spatially overage measurements (and/or average measurements from different levels) then use the averaged measurement in the FIR Designer workflow.
Best regards,
EA Support