We have recently published an article about the perception of focused sources in Wave Field Synthesis in the Journal of the Audio Engineering Society.
It is open access and can be freely downloaded and distributed.
Hagen Wierstorf, Alexander Raake, Matthias Geier, Sascha Spors. Perception of Focused Sources in Wave Field Synthesis. In J. Audio Eng. Soc. (2013)
Supplementary material can be found on figshare.
There you will find data from the experiments plotted in the figures and a video showing the geometry of the setup together with listening examples.
All stimuli from the experiment can be listened to at the supplementary material for a contribution to the 129th AES Convention.