f the array where we have tested that they are
                // consistent.
                should(actual, 'IIRFilter for Biquad ' + filterType)
                    .beCloseToArray(expected, errorThreshold);

                let snr = 10 * Math.log10(computeSNR(actual, expected));
                should(snr, 'SNR for IIRFIlter for Biquad ' + filterType)
                    .beGreaterThanOrEqualTo(snrThreshold);
              })
              .then(() => task.done());
        };
      }

      // Threshold