Danley DNA 10K4, User Manual

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smearing the arrival time). The LIR crossover can thus be described as having a flat Group Delay
response, and thus entirely free of Group Delay Distortion.
The shape of the LIR crossover filter is quite similar to a 4
th
order or 24dB/Oct Linkwitz-­‐Riley filter,
and maintains zero phase difference between the adjacent bands across the crossover region to
keep the polar response rock steady.
FIR Linear Phase Equalization
The Input High-­‐Shelf Equalizers use Finite Impulse Response (FIR) filtering to produce Linear Phase
equalization; that is all frequencies are delayed by the same amount, perfectly preserving the
transient response. This can also be important in applications where different amounts of EQ are
applied to different parts of a speaker cluster, such as to add 'Throw' EQ boost so that parts of
cluster which are throwing further can have HF absorption correction added. If this EQ is not linear
phase, then the zones where the speakers combine may suffer frequency response anomalies.