Tonal Balance and Equalizers in The Production of Audio

Equalizers are a very well-known aspect of any engineer’s life. Even for the average person who has no real knowledge of audio engineering knows what an equalizer is and for the most part how it operates in a plain world setting. Equalizers have gone through a lot of major changes throughout the years, but they have kept their main purpose and functions about the same. In the early years of equalizers, they were used for audio receivers and phonographs to help fix issues of clarity. They were fixed and integrated into the actual circuits of the systems and couldn’t be altered afterwards. Through the movie industry, with the inclusion of sound, came an emergence of external equalizers that could be varied. Most notably, John Volkman’s external equalizer design from the 1930s featured a set of selectable frequencies with boosts and cuts and is sometimes considered to be the first operator-variable equalizer.

After 1950 the equalizer began growing even more for use with post-production for audio recordings and were used for speech enhancements. Graphic equalizers were giving an extra help with being able to add and takeaway necessary frequencies to a certain extent but due to their design of being locked to a certain frequency, there was still a limit to what could be done. The evolution of audio equalizers has progressed that negates the stated issues.

With the advent of parametric equalizers, there became a more precise method of filtering out frequencies that was not before possible. Parametric equalizers were able to sweep across frequencies and then could be cut or boosted to the necessary levels. This would greatly help with being able to lower unwanted noise that could come from boosting frequencies in a graphic equalizer that you could control the exact frequencies only a specific band. Throughout the years there have been various brands of equalizers that have come to the market and each have their own characteristics that make each of them unique. One of these such equalizers is the Manley Labs Massive Passive equalizer. Its name reflects its design that runs off of passive electronic components. Passive components do not require an electric signal to energize them, instead they impart their characteristics when a signal passes through them.

It also uses a makeup amplifier that runs off of six valve tubes that counteract the electrical losses caused by the passive components (2013). Emulations of this specific equalizer has become available from the Universal Audio company with their advent of the UAD2 Massive Passive plugin. Universal Audio has gone through various steps to emulate this hardware and transform it into a software replica that is able to replicate the distinct characteristics of the Massive Passive. To further add to the authenticity, the plug in affects the sound even when the EQ sections are disengaged, simulating the coloration made by just running audio through the transformers and valve circuitry.

As the years go on, equalizers will continue to play a vital role in the production of audio. With new inventions creating new and innovative ways to shape frequencies equalizers will always have a part in the way we interact with sound and how we continue to shape what we hear and create.