DSP Filter Type
DSP filter type identifies whether digital audio processing uses infinite impulse response (IIR) filters, finite impulse response (FIR) filters, or both.
These describe how a filter is implemented, separately from its frequency settings. Either approach can shape the audio response; the available adjustments and timing behavior depend on the design.
DSP Filter Type — Equalizer
In an equalizer, IIR filters commonly provide parametric bands with frequency, gain and bandwidth controls. FIR filters use a set of coefficients and can provide detailed amplitude and phase correction. A processor supporting both may use them for different parts of the signal path.
Compare the actual correction controls, supported filter length and processing latency. FIR support does not mean every loaded filter has linear phase, and a phase label alone does not identify the implementation. A DAC's reconstruction-filter menu is a separate feature from the equalization filters described here. Analog equalizers do not use either digital method.
DSP Filter Type — Crossover
In a digital crossover, IIR or FIR filters divide the signal into bands for separate outputs. FIR can allow amplitude and phase to be designed independently, while IIR commonly implements selectable crossover slopes and alignments. The available filter types determine which crossover designs the processor can implement.
Compare supported slopes, channel allocation and latency together with filter type. A linear-phase FIR crossover may add delay that matters when combining its output with another signal path. FIR alone does not promise a particular slope or perfect driver integration. The acoustic result also depends on the drivers, their placement and the chosen settings.