The existing lowpass and highpass BiquadFilter implementation has a defect where valid filters cannot be represented. To fix this, the filter formulas were updated. However, the new formulas will cause a change in the output of the filters.
Docs: http://webaudio.github.io/web-audio-api/#filters-characteristics
Samples: https://github.com/GoogleChrome/web-audio-samples/wiki/Detection-of-lowpass-BiquadFilter-implementation https://rtoy.github.io/webaudio-hacks/more/biquad/biquad-lowpass-q.html?usedB=true