Transient Shaper, in some cases called transient designer or modulator, is a type of audio processor whose core is designed quite similarly to the compressor. It could be best described as a level-independent dynamic processor. It is similar to compressor and expander effects but comparing to them its effect does not vary with signal level.
One of the main challenges in audio engineering is to place elements right in the mix. Sometimes is hard to hit the fine line between presence and domination especially with percussive sounds. A transient is a high amplitude, short-duration sound at the beginning of a waveform that occurs in percussion sounds. They are non-harmonic sound content which are affecting character and brightness as well as perceived distance of the sound. In the late 90`s company by the name of SPL revolutionized the music production and recording industry by introducing their, now famous, Transient Designer hardware effect processor. The processor used a combination of VCAs (voltage controlled amplifiers) and envelope followers to clamp down on specific areas of a sound’s transient events.
In the core of the mentioned effect lays SPL`s “differential envelope technology“ which allows producing level-independent dynamic processing. Unlike compressor effect, transient designer had the ability to transparently shape the attack and sustain characteristics of sounds no matter their level and without the need for threshold and other parameters found in compressor effect. In fact, when SPL brought out their original transient designer, engineers were so taken with the ability of the unit to completely transform their drum tracks that many of them saw the unit as an absolute studio essential. Although the same thing is achievable using a standard compressor or gate effects, many producers find the speed of achieving the desired effect with transient processing simply amazing.
Attack and Sustain
The base of every today’s transient processing hardware unit or software plugin are two main controls, the attack and sustain. By controlling the attack level this effect gives direct control of the presence of the sound. By changing the sustain level it is possible to change room and density of the sound. When working with drum sounds if you increase the attack the drums will be in front of the mix.
On the other hand, reducing the attack will result in placing the drum sounds further back in the mix. By reducing the sustain level it is possible to get tighter, more aggressive sound. Opposite of that by increasing the sustain the result will be more dense and roomy sound. Besides drums, this effect can be placed on many other types of instruments that possess clear transients in their signals.
In recent times, there are many similar hardware and software versions of this effect. With some differences in the design and parameters, they are functioning more less in the same way with inevitable attack and release controls.
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