The latest version 4.4 releases of FIR Designer and FIR Designer M introduce new features which expand functionality, improve usability and accelerate the filter design process.
Plot Export
Any plot can now be exported as an image file (PNG format), with a user-defined pixel width and height, for consistency. Also, any individual plot trace can be exported to a multi-column text (TXT) file, for loading into Excel or other plotting software.
To access plot export, click the button on the lower right of each plot.
Especially useful for documenting designs and preparing presentations, the new Plot Export functionality avoids the need to use third-party screen capture software.
FIR Designer M Plot Export dialog
Impulse Response Windowing
The ‘Import’ tab in FIR Designer (or Channels>Import in FIR Designer M) now includes a windowing option for the loudspeaker measurement impulse response. Impulse response windowing can be useful to reduce or eliminate the effects of room reflections, at the expense of low-frequency resolution.
A new ‘Frequency Varying Time Window’ is available which has a longer effective window at low frequencies and progressively shortens at higher frequencies. Also available are all windowing options from the FIR filter Export tab – Boxcar, Cosine Tapered, Modified Adriene, Hanning, Blackman-Harris and Kaiser-Bessel – with adjustable start and end lengths.
When enabled, windowing is applied prior to frequency smoothing.
FIR Designer M Windowing examples: Off, Frequency Varying Time Window, Hanning
Channel Plot Customization
Specific to FIR Designer M, plot displays can now be customized separately per channel within each tab of the channel workflow, so that different magnitude and phase traces can be v