FIR Calculation
In this page the FIR filter coefficients are computed starting from default settings (or from the
parameters set of the FIR Wizard project, when a project file is recalled at the Wizard home page).
The two graphs in the screen show the time and frequency response of:
1) the loudspeaker IR (red line), as it appears in the preceeding page.
2) the compensating FIR filter (green line), which is normalized so that when the FIR filtering is
enabled or disabled, the sound loudness remains roughly unchanged. This is very important for
performing listening tests and it is a good feature in general.
3) the convolution between the IR and the FIR filter (IRxFIR, yellow line). It represents the result
of the IR compensation process, that corresponds to what would be the IR if it is measured with FIR
processing enabled, or in other words, the new loudspeaker IR when the computed FIR filter is
applied.
4) The target magnitude curve, that is shown only in the frequency domain when the magnitude
view is selected. By default the target magnitude is flat, but it can be changed by the user as
described afterwards.
Curves in the graphs are overlaid to allow a better comparison between the IR, the FIR filter and the
resulting convolution. Anyway, if needed, each curve can be hide acting on the checkboxes at the
top right of the plotting area as shown in the picture below, where FIR filter and target curve are
hidden.
Summary of Contents for LPP-480F
Page 1: ...User Manual LPP 480F...
Page 49: ......
