Photo: Mr. Bonzai
With so many tools available at our fingertips, it's hard to imagine a time before parametric equalizers existed, but we have George Massenburg to thank for this development. In 1967, Massenburg was using a prototype sweepable EQ designed by his friend Bob Meushaw. The unit had noisy early op amps and an odd interface, but offered advantages over the graphics, program EQs and filters available at the time. Two years later, Massenburg wanted to create a more elegant interface on a 3-band equalizer (with independent control of gain, Q and frequency for each band) for a console he was designing for ITI. Only one ITI board was ever built (it's currently at the bottom of the Baltimore Harbor), but the ME-230 parametric EQ it featured was shown at AES in 1971.
It was somewhat crude, and many of the components (particularly op amps) were hardly up to today's standards, but the parametric equalizer was finally born, and Massenburg presented his findings on parametrics in an AES presentation a year later. Massenburg never patented the circuit or trademarked his term “parametric,” but continues to build (much improved!) parametric EQs sold through George Massenburg Labs.