User`s manual

The Output spectral Shape may be selected as Flat, illustrated in Figure 4-43, Figure 4-44, and Figure

4-45 above. It may also be set to Voice or Pink. See Figure 4-47.

The Attack Noise mode does not attenuate Out-of-Limits signal, but equalizes and attenuates in-

Limits signal frequencies. Figure 4-46 illustrates.

Applications Suggestions

The following suggestions may be beneficial in setting up and operating the Spectral Inverse filter.

Analyzer: The FFT spectrum analyzer automatically produces the power spectrum of the signal

entering the SIF. For SIF to be effective, a smoothed spectrum is necessary; SIF adjusts for long-term

stable noises including resonances and steady noises. Short-term effects of voice and non-stationary

noises will decrease the filter's effectiveness; therefore, the Number of Averages should be set large.

At least 32 averages are recommended, but more will give a smoother spectrum from which to build a

filter.

Figure 4-46 Attack Noise operation, Filter Amount set to 100%