Since sound waves travel in straight lines, is it possible to generate sound such that it can only be heard in a specific direction away from it's source? Normally when we generate a sound, for example when we say something, the sound we make can be heard all around us. The person left and the person right to us can hear us when we say something. I assume this is because when we say something we don't generate a disturbance on one particular particle that propagates the disturbance, but we do this on many particles in many different directions. So I was wondering if it is theoretically (or even practically) possible to make a sound (obviously by a machine and not our voice) that can be heard only for example in front of the source in a specific radius?
EDIT: I assume it is not possible because particles aren't perfectly lined up, so when they hit each other and propagate the disturbance the direction of the sound wave gets deflected. But then again, I read that sound waves travel in straight lines, so what does this mean exactly?