The Moog Bass
The first of twelve basslines built a step at a time, and the step that matters turns out to be the filter you can't get from Web Audio. A Moog's ladder is four one pole stages with feedback around all four, and that feedback subtracts the input, which is what eats the bass: for an 8.5 dB resonant peak it pays 10.4 dB of fundamental while the peak itself rises 12.1 dB. Two cascaded BiquadFilterNodes put up the same peak within 0.1 dB and pay nothing at all, so at matched peaks the ladder sits 12.5 dB further down. First of twelve.