FIR Designer

Create finite impulse response (FIR) filters and mixed FIR + IIR filtering solutions for loudspeakers.
Load filters into any FIR capable speaker processor or amplifier. Advanced Direct-to-Processor function available for some brands.
Using FIR Designer’s single-channel workflow, build a complete loudspeaker preset (DSP signal chain) by generating Summary Output files in combination with FIR &/or IIR filter files.
Evaluate filtering and presets in real-time using auditionDSP.

Create loudspeaker tunings/presets with specific magnitude and phase characteristics.

Match different makes & models of loudspeakers in install systems.

Perform system/room correction.


  • Intuitive, fast workflow from impulse response import through to filter coefficient export
  • Continuous filter calculation and error display as parameters are updated
  • Two workflows
    • FIR filter design from a loudspeaker measurement
    • Direct FIR design, without a measurement
  • FIR only or mixed IIR & FIR design
  • FIR Filter sample rates: 12, 24, 44.1, 48, 88.2, 96, 176.4 and 192 kHz
  • IIR filters (unlimited)
    • Bandpass, low and high shelf
    • Low-pass and high-pass Bessel, Butterworth, 2nd order variable Q, Chebyshev I & II, Elliptic, Linkwitz/Riley & Neville Thiele notched crossover.
    • IIR coefficient export: regular transfer function and MiniDSP formats.
  • IIR filter modes with brand-specific parameter limits
    • Generic (all of the above filter types)
    • Biamp Tesira
    • BSS
    • Lake
    • Linea Research
    • Marani
    • Powersoft
    • QSC Q-Sys
    • RAM Audio
    • Symetrix
    • Legacy (General)
  • IIR reference mode and reference editor with IIR filter conversion between brands
  • Auto IIR function for matching a response to target with IIR filters only
  • FIR filter design
    • Magnitude Adjustment using common filter prototypes, above, and with minimum, linear and maximum phase options.
    • Phase Adjustment using minimum-phase and maximum-phase all-pass filters, and a unique 4th order all-pass parametric phase filter
    • Automatic magnitude correction with smoothing
    • Automatic phase correction with smoothing
    • EQ Voicing (post target) using common filter prototypes
    • Unlimited filter prototypes and automatic correction frequency bands
  • Target responses:
    • User-defined parametric magnitude target with low frequency shelf and unlimited slope segments
    • Magnitude filter prototypes with minimum, linear and maximum phase options
    • All-pass filters with minimum and maximum phase options
    • Impulse response target from file (with options to use magnitude only or magnitude and phase)
    • Both user-defined and file responses combined.
  • auditionDSP: a built-in processor & audio player for listening to custom processing (filters &/or presets) during development
  • Use coherence in automatic magnitude and phase correction algorithms
  • Load and view loudspeaker impedance
  • Import measurement resampling (measure at one sample rate and export filters at any sample rate.)
  • Second View: an additional window for any workflow plot, which can be viewed on the primary display or on a different monitor/display.
  • Continuous Wavelet Transform display for time/frequency impulse response analysis.
  • SMAART® Control for live measurement streaming and capture directly into FIR Designer.
  • Comprehensive range of measurement file formats (TXT – magnitude/phase/coherence, TXT – Klippel, TXT – samples, WAV, STO – SysTune Overlay, TRF – SMAART Trace, ETM – Easera measurement, SPK – Monkey Forest and more)
  • Multiple export formats compatible with most processors and amplifiers (including Powersoft, BSS, miniDSP, EV/Dynacord, Linea Research, DFM and more)
  • Processor gain, polarity & delay settings
  • Generate complete loudspeaker presets via the processor channel summary setting export option
  • Supplementary Responses window for seeing the effect of processing on other measurements, including a polar map (heatmap-style contour plot).
  • Direct-to-processor (DTP) functionality:
    • To LAKE PLM & D series amplifiers and LM series processors. Requires the FIR Designer LAKE plugin and the LAKE FIR 3-way module.
    • To Powersoft X, Ottocanali, Quattrocanali and DueCanali series amplifiers. Works via an XML file which can be loaded into the amplifier’s “Speaker EQ” or “Output EQ”.
    • Optionally side-load pre-existing FIR filters (with automatic sample-rate-conversion, if necessary) from other programs for transfer to LAKE &/or Powersoft. Rewindow longer FIR filters to the LAKE & Powersoft tap limits.
  • Integrated Measurement Averaging
    • Load up to 200 measurements of any type
    • Multiple level matching options
    • Auto time alignment with manual adjustment
    • Four averaging modes: Complex, Power (flat phase), Power (minimum phase) and Power (minimum phase + reference excess phase)
    • Export averaged response in a variety of formats.
  • Moveable license: deactivate and reactivate on a new computer.
  • macOS and Windows versions. (Windows 10 22H2 & above. Or macOS 11 above)
Compare FIR Designer & FIR Creator features on our Filter Software Comparison Table.





Measurement Averaging

Continuous Wavelet Transform Display

FIR Designer screenshot: Continuous Wavelet Transform Display

Target File with Non-flat Phase

Direct Design Mode

SMAART is a registered trademark of Rational Acoustics LLC, Connecticut, USA.