What is Immersion?

Spaciousness versus 'Immersion'

This is an extract from my dissertation literature review which explores the differences between spaciousness and what this project will term 'immersion'. This definition of immersion will be used to underpin the primary aim of the project, therefore it is crucial that the reader is able to understand the proposed distinctions between spaciousness and true immersion. This review will also allow me to successfully define the scope and context of the project. It is also important that I use this information to set my own boundaries to keep the project focused.

Extract:

The primary difference between conventional techniques where the surround channels are used for cues to provide 'spaciousness', and the techniques for creating an immersive audio environment, is how the audio is captured and presented. There are several methods for capturing and replaying multi-channel audio that provide spaciousness but fewer that are capable of creating a sense of true immersion. We can use a combination of techniques that allow traditional methods to create a sense of immersion and as this project seeks to determine if methods such as Binaural and Ambisonic approaches can provide that to a greater degree compared with traditional approaches, it is important to discuss the context for which these techniques are intended.

According to Holman, 'spaciousness applies to the extent of the space being portrayed, and can be heard over a 2-channel or 5-channel system' (2000: p.216). In practice it is possible to determine the size or extent of a location in which a recording took place by the reverberation or diffuse field characteristics that accompany the direct sound. The ability of a 2-channel system to reproduce this is limited by the fact that the image itself can only exist between the two loudspeakers. The image that appears between any two loudspeakers is referred to as the phantom image. Although the space can be imagined and represented by the phantom image there is little chance of a listener thinking that they are present in that space if only two loudspeakers are employed. He then goes on to say that 'envelopment...applies to the sensation of being surrounded by sound, and thus being incorporated into the space of the recording' (2000: p.216). This envelopment does require the use of at least a multi-channel reproduction system to create this sensation. With multiple speakers and multiple phantom images created between each source the listener can begin to imagine the sound field that the system aims to represent.

Holman's concepts of the "Direct/Ambient" approach where the front two loudspeakers provide the direct sound and the spaciousness is conveyed through the rear channels, and the "inside the band" approach, where direct sound and ambient sound do not follow these conventions as a result of direct and ambient sound being played through any loudspeaker, determine the audio perspective that the viewer is offered (2000: p.102). When viewing a visual sequence it is important that the audio picture supports the narrative conveyed through the visual picture by creating a sense of continuity between the two, unless of course the sound designer or director is trying to juxtapose the two to create an entirely different narrative. The sense of direct involvement can only come about if the viewer is experiencing the sound that the image suggests, i.e. from the perspective offered by the camera angle. Chion uses the term 'spatial and subjective point of audition' to make the distinction between the possibilities offered by camera angles and audio perspectives. He refers to the spatial designation as 'the place from which I the spectator see; from what spatial location the scene is presented' and the subjective designation as the character's point of view as seen by the spectator (1994: p.89). Understanding these distinctions is crucial for the sound designer to successfully fuse the two entities and create a true sense of envelopment.

In the case of the audio and visual examples provided within the context of this research the perspective falls into the subjective category as the camera angle is providing the viewer with the character's point of view. It is also hoped that when the ‘inside the band’ soundtrack accompanies the visual sequence, the viewer will 'become' the character by seeing what s/he sees and hearing what s/he hears.

End

So what can we take from this extract? Immersion, within the scope of this project means envelopment, being surrounded by sound, and with that comes the possibility of audio functioning as a tool that helps to involve the viewer in an experience.

To establish if there is any real benefits of immersion over spaciousness then this project will need to produce films and soundtracks using the techniques outlined above as a means of finding this out. Further research into similar technologies aimed at providing such experiences will need to be explored and further exploration of techniques and processes will need to be carried out.