The specific objectives of the proposed project are designed to produce results that will aid the product designer and/or service provider in choosing engineering compromises in sound delivery systems involving surround sound capability. The reason for concentrating on the issue of degradation is in order that one may determine what degrees of compromise are possible in system and service design, taking into account the likely effect on the verdict of the end user. The following are the primary research objectives:

  1. To quantify the effects of specific controlled degradations in multichannel sound quality on the mean opinion score (MOS) according to proposed EBU and ITU test methodologies.
  2. To measure the programme and context dependency of these effects (does the effect depend on the type of programme material used, the environment implied by the programme and the recording technique?).
  3. To measure the subject variability of these effects (does the effect depend on the expertise/experience of the subject, and what is the degree of consistency in judgment among subjects?).
  4. To measure the listener position dependency of these effects (are some effects more or less noticeable in different listening positions?).
  5. To compare alternative methods for the evaluation of intermediate audio quality including the use of specific descriptive rating scales.
  6. To quantify the effects of spatial sound quality artefacts when (i) the subject is engaged in a task related to the sound source whilst a visual image is concurrently present and (ii) the subject is engaged in a task related to a concurrently presented visual image/scene.

These experiments are designed to explore task-dependency and modality interactions in a multidimensional environment, and will provide an excellent basis for subsequent projects dealing with multimodal sensory interaction in later years.