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# Biquadratic IIR filters

Apply biquadratic filters to single-channel and multichannel data.

## Topics

### Biquadratic IIR Filters

  <doc://com.apple.accelerate/documentation/Accelerate/equalizing-audio-with-discrete-cosine-transforms-dcts>

[`Biquad`](/documentation/Accelerate/vDSP/Biquad)

A single- or double-precision biquadratic filter.


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