VA can insert digital filters into the signal path before display, measurement or output. This makes it possible to analyse a filtered signal or use the PC as a real-time audio processor.
Processing types
- Low-pass, high-pass and band-pass
- Band-stop and notch
- DC removal
- FIR and IIR filters
- Graphic equaliser
- Routing of the processed signal to output
Use in measurements
A filter can isolate the band of interest, reduce noise or interference and simplify later measurements. Remember that filtering changes amplitude and phase: the result represents the processed signal, not the original input.
Always check gain. Band summation, resonances or non-normalised coefficients may cause internal or D/A-output clipping.
Read more in the Visual Analyser Handbook
This page is an operational introduction. Chapter 5 — Digital filters of the forthcoming book covers theory, controls, algorithms, examples and measurement notes in much greater depth.