Security without audio is akin to watching a silent movie.
Without thinking about it — you may have noticed that sound (audio) travels slower and shorter distances than light (visual). This has to do with the fact that sound travels at a rate of about 1,100 feet per second while light travels at 186,000 miles per second.
While the difference between the two is quite dramatic, sound is further affected by a governing law of physics known as the Inverse Square Law.
Given that humans typically speak somewhere in the range of 60dB, we can see that sound can only travel a certain distance. Because of the speed, distance, and other environmental factors affecting audio, we can see that audio is quite sensitive to external factors and audio capture close to the sound source is important.
Translating this to audio in security, the further away from the sound source, the more the sound level decreases. In turn, audio quality diminishes.
Omni-directional microphones like the Verifact A have a range of 15 ft. in each direction for a total range of 30 ft.
While directional microphones can capture audio for about 8–12 ft in one direction, this doesn’t mean you won’t be able to capture audio beyond 15 ft. However, it does mean that audio beyond 15 ft will be affected.
Learn more about pickup patterns and how they affect range and audio monitoring here.