A level in four layers of sound. useMusic plays one tune in two files and swaps to the muffled one in the pond without losing its place. The meadow is a sound with a zone, full on the grass and fading off it. The birdhouse is a placed sound with a cone, louder in front. The coin is a plain effect. The ears are on the player, with useAudioListener.
Arrow keys to walk and Space for a coin; headphones tell front from behind.