Project #1 - Uncanny Dynamics

To the human ear, the ratio between the quietest sound the ear can detect to the level which begins to cause pain is about 90db (1 part to 10 trillion).

My first project demonstrates a practical maximum dynamic range in a large air conditioned room containing about 40 humans walking about and a number of computers. The project, played on the 5.1 sound system in the ACTLab, consisted of a short series of computer generated tones which I used as a volume adjustment reference followed by three selections from my recordings using a Core Sound TetraMic, a commercial tetrahedral ambisonic microphone.

The first sounds are of a group of feral cats to which I offered a meal around the microphone. Their mewing is followed by my distributing the dry cat food from a tin cup around the mic, then the crunching sounds as they enjoy the meal. Next is a flyover of an American Eagle jet recorded about 0.7 of a mile from the north end of runway 17R of Austin's Bergstrom Airport. At no extra cost, insects were singing from a wooded area to the left of the microphone while U.S. Highway 183 was to the right.

The last segment is the final seconds of a fireworks display recorded at the Dell Diamond baseball complex near Round Rock, Texas. The explosions from the display finale end and the crowd cheers. In the following quite moments, voices can be heard as car engines are started and people leave the park.

The final seconds of this last segment is in extreme dynamic contrast to the fireworks and in its quietest moments is about 56db below the peak levels.