We’re all familiar with terms like distortion and saturation. These tools allow us to add warmth, character, and additional harmonic content to our sounds. However, there's another tool at our disposal that may be less familiar - the waveshaper. In this article, we'll explore waveshapers and shed some light on their unique capabilities and applications.
Distortion Vs Saturation
Before discussing waveshaping, it's useful to understand the distinction between distortion and saturation. Distortion is a broad term encompassing any alteration of an audio signal. If it’s changed then it’s been distorted, however we tend to reserve this term for processes which add additional frequency content to the signal. Saturation, on the other hand, refers to a specific type of distortion that emulates the behaviour of analogue circuits. It aims to recreate the warm, nonlinear characteristics and additional harmonic content associated with analogue equipment.
Arbitrary Distortion
Waveshaping, in contrast to saturation, is a more arbitrary form of distortion. Instead of emulating the effect of specific hardware or components, waveshapers provide a versatile and highly customisable means of manipulating audio waveforms. At its core, a waveshaper plugin applies a mathematical function to the input signal, altering its shape, often generating harmonically rich and complex tones.
Understanding The Transfer Curve
To achieve these transformations, waveshapers employ what is known as a "stateless transfer function." This function maps input values to corresponding output values, allowing for flexible shaping of the waveform. The transfer curve shares the same format as those we are familiar with found in dynamics processors. If the transfer function is a diagonal line from bottom left to top right then no change happens, input equals output in the same way as a compressor transfer curve. However this curve offsets the individual cycles of the waveform, it ‘shapes the wave’. Hence the name.
Any deviations from 45 degrees either shifts the waveform either up or down from where it would be during its cycle. This can introduce very unnatural shapes and a great deal of inharmonic content which isn’t musically related to the input.
Filtering and Waveshaping
Introducing filtering alongside waveshaping opens up additional control and new creative possibilities. By applying filters before or after the waveshaper, you can sculpt the frequency content of the sound, emphasising or attenuating specific ranges. This can be very useful to sculpt the sometimes unpredictable results of waveshaping.
Aliasing And Oversampling
Just like distortion and saturation, it’s important to consider the use of oversampling when using waveshaping, particularly when waveshaping can produce so much additional frequency content which can cause significant aliasing. Aliasing occurs when high-frequency content is incorrectly represented at lower sample rates, resulting in unwanted artefacts. To mitigate aliasing, oversampling is often employed. By increasing the sample rate temporarily during processing, the plugin can better capture and preserve the high-frequency information, yielding cleaner and more accurate results.
How To Use Waveshaping
By pushing signals into extreme distortion territory, you can create extremely aggressive tones. But it’s important to understand that all saturation plugins are waveshapers, they just limit the processing to yield a specific result. A waveshaper can create subtle effects like gentle saturation, but with far more breadth of control, which if you are seeking to recreate a specific sound also means more room for error! Waveshapers are also useful in sound design, enabling the creation of unique and unnatural textures. In genres which suit extreme processing, waveshapers can introduced unmatched amounts of distortion and filth!
Waveshapers provide a fascinating and versatile means of distorting audio waveforms. Unlike the more familiar saturation plugins, waveshapers offer an arbitrary distortion canvas. The world of waveshapers is definitely worth checking out!