Free space is a stricter concept than an unbounded region
Evidence
Free space is a region in which the sound wave is free to travel in any direction. That is, there are no obstructions or changes in the propagation medium to affect its travel. Therefore, free space is a form of unbounded region. However, not all bounded regions are free space. For example, the wave may be coming out of a tube in a very large wall. In this case there is a transition between a bounded and an unbounded region but it is not free space, because the wave cannot propagate in all directions. — David Howard, Jamie Angus, coustics and Psychoacoustics, 355
Categorization
Category: Definitional Content
- DEFINE: Distinguishes free space from unbounded regions — a key boundary condition distinction for practical acoustics.
Related
- Free space requires unobstructed propagation in every direction, not mere unboundedness. (similarity 0.98)
- Free space requires freedom in all directions, not just unboundedness. (similarity 0.96)
- Free space requires unobstructed propagation in all directions (similarity 0.95)