Spectral "Compensation"?

weefuzzy · January 3, 2021, 7:16pm

It’s hard-coded to that because the coefficients in the standard are only given for 48k:

To get equivalent coefficients for other sampling rates would require a bit more reverse engineering. This seems to be the bit of Gerard’s code that initialises the filters for arbitrary sample rates

github.com

flucoma/flucoma-core/blob/97f68a56e9d773d67a556e78cc937252b4e77f89/include/algorithms/util/KWeightingFilter.hpp#L22


#include "../util/AlgorithmUtils.hpp"
#include "../../data/FluidIndex.hpp"
#include <cmath>
namespace fluid {
namespace algorithm {
class KWeightingFilter
{
public:
  void init(double sampleRate)
  {
    // from https://github.com/jiixyj/libebur128/blob/master/ebur128/ebur128.c
    // Shelving filter
    using namespace std;
    double f0 = 1681.974450955533;
    double G = 3.999843853973347;
    double Q = 0.7071752369554196;

Which, I guess, is based on what this library does