A website devoted to the  science of web handling

Here is a video (derived from a PowerPoint) on the physics of infrasound. It's based on work done for a client in 2003-2004. When the project was finished he gave me permission to explore the possibility of marketing the microphone and signal processing system.

The main challenge was to find an application that would support a small enterprise. None were obvious, so this PowerPoint was created and placed on line in hopes that Google would lead prospects to it. Every year or so I get a few inquiries. They fall into two categories - serious and non-serious. The serious inquiries are almost always from biologists who are studying vocalizations of animals - for example, elephants. The non-serious range from ghost hunters to chiropractors. I soon concluded that there was no prospect of a viable business. Quantities would be so small that there was no possibility to sell anything but handmade costly ($5,000 to $10,000) prototypes which no one could afford to buy.

It should be noted that Microflown no longer markets bare sensors needed for making the microphone and the TestPoint software used for the signal processing is no longer available.

I have left the video up because it summarizes some interesting physics which may be helpful to researchers. My advice to anyone needing infrasound equipment is to talk to companies such as Larson Davis and G.R.A.S.   They have microphones that can get as low as 3 Hz. Many types of microphone systems can be rented at the Modal Shop.