Support Forums › Forums › FIR Designer M Support › DFM Question › Reply To: DFM Question
We don’t have much experience tuning line arrays. I know some systems, that don’t have FIR capability, do perform HF adjustment (as you described) using IIR filters or minimum phase FIR filters (which are essentially equivalent). The brands I’m thinking of treat the line as roughly 3 zones – short throw (lower boxes), medium throw (mid boxes) and long throw (upper boxes).
With FIR you can do things somewhat differently. For example you can EQ the whole array as one using IIR (or minimum phase FIR) – this retains the line array behaviour, particularly at LF and MF – then use FIR for “linear-phase” filtering of upper MF and HF for different groups of cabinets – upper, mid or lower. My understanding is that L’Acoustics array optimisation takes this approach, and some other brands may also.
Linear-phase FIR filters are a subset of FIR filters and have the same effective delay across all frequencies. For more on linear-phase FIR filters, read
Best regards,
EA Support