An attempt to reproduce the effect of the drug diisopropyltryptamine on auditory perception.

The effect was created with software called SPEAR, which stands for Sinusoidal Partial Editing Analysis and Resynthesis. Essentially, the original sounds were broken down into number of parallel sine waves, which are layered together to "resynthesize" the sound. Before resynthesis, however, I applied a global frequency shift to each partial, causing the harmonic relationships between the partials to be distorted (two partials with a 2:1 frequency ratio might now have a 1.8:1 ratio).

This gives many sounds a metallic or bell-like timbre, which is exemplified particularly well in Keith Jarrett's piano. It also breaks down the traditional harmonies of tonal music. DiPT had a virtually identical effect, which leads us to conclude that the human brain must similarly deconstruct sound into sinusoidal partials.

Ralph Blum (DiPT effect)

TheAppleCore