A musical lowshelf filter (two pole recursive, direct form 1). Filter frequency, gain (in decibel) and quality (resonance) must be specified. The filter frequency is expected to be normalized, ie. between 0 and 0.5. The normalized frequency is simply the target frequency divided by the sample rate (eg. 1000Hz / 44100Hz = 0.02267). To let the filter ring out, a number of samples can be specified that will be appended as zeros to the input, and extend the filter response by the same number of samples.

Input parameter:
double[] inputArray, double normalizedFrequency, double gainDb, double q (, numAppendedSamples)

The input is not modified.

Writing good docs:

Communicate Value

A good introduction should make it clear why someone might use your API.

Show and Tell

Give examples of using your API and explain those examples.

Easy to Skim

Ensure your docs are structured such that familiar users can quickly jump to the content they want.


Revisit your docs after making breaking changes or adding new features to keep them up-to-date.