Oui, ils utilisent le phénomène de Haas. Ils en parlent dans la vidéo je crois.
Ca me parait une version simplifiée de Haaze https://klevgrand.se/products/haaze que je possède et qui est très sympa.
Panning an audio signal can be done in several ways, where the most common is to alter the volume on one channel. This is a CPU efficient way (and many times the best) to achieve a sense of positioned audio. Almost every DAW and mixing console have this feature built-in.
Another way is to add a short delay to one of the channels – the Haas method. This renders a richer sound, but can also make a sound come off as somewhat unnatural.
A more elegant way is to apply a low pass filter to one of the channels. This maintains the audio energy on both channels, but at the same time makes it sound positioned. This works very well on transient rich sounds like drums or other percussive instruments.
Ce n'est pas l'effet Haas.
Pour les utilisateurs de Live, voici un plugin M4L basé sur le même principe, mais en plus puissant (et avec aussi un "Doppler manuel")