VA - Paradigm Shift

The z-plane records logo is a truncated sinc-fuction. Its truncated because it goes to infinity. If you theoretically could use the infinite sinc function as an impulse response in a filter you would have the holy grail of filters, a completely square edged filter with no ringing in the edges. Perfection. The Z-plane is the complex plane where numbers are 2-dimensional, and its how you crunch numbers in signal processing.