I am training an animal (let's assume it's a rat) to do sound-source localization in a cylindrical plexiglass chamber that is approximately 30 cm in diameter (see figure). That is, the animal must approach the speaker that is presently on (there are four speakers present, one is on, the other three are off). Sound is 70dB at 10kHz.
They are getting confused, perhaps due to echoes or reverberations in the chamber. I am not sure how to optimally design the chamber (i.e., frequency and volume of sound source, and diameter of cylinder) to minimize confusion.
In case this is a known problem from partial differential equations, the cylinder is closed on the floor, open on the top and we can consider the speaker a point source for all intents and purposes (it is a piezo buzzer with a pure tone).
We have argued about whether sound should be extra loud to help them find the right source, or perhaps quiet to minimize echo/reverb in the chamber. Ultimately I think there is an optimum value to minimize all these effects. I have cracked open my Giancoli Freshman Physics book but it didn't get beyond unencumbered sound travel, and the basics of wave reflection (e.g., angle of reflection = angle of incidence: e.g., what you'd find at Wikipedia - https://en.wikipedia.org/wiki/Reflection_%28physics%29).
Adding a padded inner surface to dampen reflection is not an option because the animals will climb it and escape to freedom.
Their errors seem fairly random. For instance, when the speaker turns on to the right they go to the left instead. I know they can do these types of tasks in general: when I replace speakers with little LED lights, they learn it in a couple of days and they are very happy. I really think this is a problem with the acoustical physics of my setup.
[If someone were to suggest a simple piece of software to model sound in simple reflective enclosures I would not complain about it--I searched and didn't find it--but I am not asking for such a tool because I know this question would get closed for asking such an off-topic question about tools :)]