Description of the Space: 

This is a rectangular basement parking garage located underneath the Scripps College field. The space itself is made up of only concrete walls and pillars that cause sounds in the space to produce a prolonged echo. The lot was about half full, however, it must be noted that there were no cars around where the balloon was popped so as to avoid any of their alarms going off. There were no background sounds. The space was pin-drop silent while this balloon pop was recorded.

Recording Setup:

I used a TASCAM DR-40 sound recorder to record this reverberant space. My friend burst the balloon while I operated the sound recorder. The recorder was located approximately 4 feet from the balloon, which was popped in the middle of the parking lot.

Reverberation Time:

30 dB decay: 1.3 seconds

50 dB decay: 2.3 seconds

60 dB decay: –

decay to background level: 2.9 seconds

Acoustic Description:

Being an underground car park, the space was surrounded by nothing but cement (the walls, ceiling, pillars, and floor!). This meant that there was bound to be a prolonged echo no matter what. The fact that the parking lot was relatively empty only increased the chances of this happening. It is because of this echo that it takes the surrounding area so long (2.9 seconds) to return to its original sound level.

Due to the fact that the balloon was popped in a relatively enclosed solid space, it reached a massive 89.135 dB as its maximum intensity. From the spectrogram above we can see that there was barely any background noises prior to the balloon pop. This graph also shows that the sound lingers before dissipating slowly.