Realistisk formidling af virtuelle lydkilder - 4-to-one

The following is a short summary of some of my experiences with the system in use. The experiences
are not based on scientific and systematic user tests of well-defined aspects. Rather, they are based on
open and improvised try-outs. Beside myself, approximately 10 others – primarily friends and family –
have tested the system. Some of them more than once. I know that this can seem as quite a fragile
foundation to base my experiences upon. However, I still believe that I can present experiences with
some validity.
Generally, the users seemed to react positively to the tests – the system generally and overall seemed
to work as intended. I know that friends and family generally would do so regardless of their actual ex-
perience, but I also feel capable of decoding to what extend a positive response is pretended. Of course
there were situations with ‘breakdowns’ in the illusion of realism. One of the reasons for such break-
downs might be that the users did not use personalized HRTFs. To get a more precise knowledge of
what caused the breakdowns, more user tests must be conducted.
A more specific experience was a noticeable lack of user head movements. The users did generally not
rotate their head, even though that I, beforehand, had explained the system’s functionality. One of the
reasons for this might be that our general experience with headphones is that rotating your head has no
influence on the sound, and another reason is probably that the listener doesn’t ‘gain’ enough by rotat-
ing his/her head.
The tests of the system seem to emphasize that an implementation of position tracking of the listener
would greatly enhance the system’s potential in an experience-oriented context. This would, I presume,
also make the effects of listener rotation more meaningful and appealing to the users.
The tests also pointed to the importance of the simulation of room acoustics in such a system. In fact, it
seemed to be more important than I initially assumed, and therefore it deserves more attention than I
have given it during the development of the current system.
Concluding this summary, I will list some aspects of relevant future work.
One such aspect is to implement and gain experiences with position tracking of the listener. Further-
more, it could be interesting to investigate the technology in other contexts such as movies and com-
puter games. It will also be relevant to examine the quality of binaural synthesis in the frequency domain
compared to synthesis in the time domain, as well as examining the quality of different ways of perform-
ing frequency domain synthesis. Generally, it will be relevant to conduct a lot more, and perhaps more
systematic, user tests. These maybe focused on specific aspects of the system, for it does consist of a lot
of different technologies and techniques that can be improved individually. And future developments in
technology will certainly make it possible to create more realistic, more immersive experiences of the
spatial aspects in sound reproduction.
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