Listen to a Bach chorale with four instruments in different directions. Uses your webcam to track your head and render the instruments in space.<p>The interaural time and intensity differences are relatively straightforward to do — the sound source is here, the ears are there, introduce delay for speed of sound and attenuate by inverse of distance.<p>For the direction-dependent frequency attenuation and emphasis, I used a very small neural network to learn an HRTF (head-related transfer function) interpolating between head-related impulse responses at fixed directions.<p>Everything's running in the browser.