MicroPitch

Eventide originated the micropitch effect by accident in the early 1970s with the introduction of the world’s first digital audio effects box, the H910 Harmonizer^®. The design of the H910 predates large (and medium) scale integrated circuits, including analog-to-digital converters, sample rate standards and digital signal processing algorithms. The H910’s system clock was not crystal-based but instead used an LC (inductor/capacitor) oscillator circuit which proved to be just a tad unstable. As a result, the pitch ratio would wiggle about.

Early owners of the H910, especially studios that could afford two, discovered that setting the pitch ratio on one H910 to ‘flicker’ between 0.99 and 1.00, while adjusting another to flicker 1.00 and 1.01, resulted in a rich spread stereo effect. And, a few adventurous engineers like Tony Visconti working with David Bowie and Brian Eno on Low, discovered that combining a tiny bit of pitch change, a short delay and feedback created something new and exciting – “Pitch Dive!”. 

Eventide’s second Harmonizer, the H949, introduced in the mid 1970s, ‘fixed’ the randomness of the H910 by incorporating a rock-steady crystal oscillator. The H949 provided a number of new features made possible by digital audio – reverse effects, de-glitching and “u PC” (“u” being engineering speak for ‘micro’) – thereby formally introducing this new effect into the pro audio lexicon. The H949 was also an early digital audio device, 100% DSP/CPU-free, predominately analog, and, to achieve small, precise, deviations of pitch it employed using a radio technique called Single Side Band modulation. 

With the introduction of the DSP-based Eventide H3000 Harmonizer®, an enhanced version of the MicroPitch effect was developed and the effect became a ‘go-to’ tool for audio pros and artists worldwide. Today’s MicroPitch continues the long tradition of offering ever-expanding capabilities to this fundamental effect.