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Why Fusion-IR is different from other convolution reverbs

Convolution reverbs are not all created equal and in this article we tell you why Fusion-IR is different from other convolution reverbs.


This revolutionary new processing technique captures the evolving character of time-varying reverbs using multiple true-stereo reverb streams that are processed simultaneously. The inputs to the convolution streams are modulated and the outputs fused into a rich, captivating space that mixes effortlessly with your music.

Fusion-IRs typically also contain separately sampled early and late reverb components for a level of mix control never before found in convolution reverbs or sample packs.

We provide sets of Fusion-IR expansion packs for LiquidSonics Reverberate 2/3 and Slate Digital VerbSuite Classics. The Fusion-IRs within Seventh Heaven and Seventh Heaven Professional further develop the concept by incorporating multiple variants of a preset so that many more dimensions of a reverb device can be reproduced.

Fusion-IR Synthesis in Illusion and Lustrous Plates take the concept to the next level, and from an algorithmic base generate synthetic impulse responses to feed to a modulated convolution engine.

It’s all in the modulation

Since an impulse response can only provide a single-shot capture of a reverb, most of the benefit of the modulation is lost. Attempts to capture modulated reverbs have in the past led to lifeless reproductions that reproduce many recognisable qualities of the original but lack their true character and do not blend organically with source material. They couldn’t fool anybody that has used the original. For years, convolution reverb has garnered a poor reputation as a result.

The perfect visual analogy of the problem is that of a photographer trying to capture the motion of cars on a highway at night. It is possible to use a long exposure blurring vehicles into a long streak of light along their path, smearing the detail but capturing an effect of the motion. This effect is what happens when one tone-sweeps a reverb; all the modulation is blurred into a single capture with impoverished definition. Alternatively, a very fast exposure captures all the details of the highway at a single moment in time, but it cannot convey any sense of the motion so much is lost in translation.

Naturally, the solution is to take multiple photographs and replay them in sequence. Using a suite of proprietary multi-sampling impulse response capture and replay technologies, LiquidSonics Fusion-IR follows the same approach for convolution as the early pioneers in motion picture.