More Pi Day + Friday the 13th + VIXI + Smorfia, Special song with guest vocal by Adam MacKay-Smith, GPT Corner, Sciencey Stuff, Sped up discussion of guitar picks.

Including:

Original song: "To Sing On Command" by Lex Plexus ft. Adam MacKay-Smith 

GPT Corner: Fog Lights + Omnidirectional Bass + Localization ITD & ILD + Sound Shadows + Sensor Fusion + Haas Effect + Brain Compression Circuits + Phonemic Restoration Effect + Fundamental Inference + Shepard Tones

Shepard Tones demonstration (Endless Series)