2012-09-05

Soundfishing

"the most important thing to understand with regards to human underwater listening is that our ears are mostly useless" via

Introducing Soundfishing, the latest sporting activity in the great outdoors of the San Francisco Bay Area.  In a city that is all about recreation, water activities, fitness, etc., what is there to do for the non-sporty among us? To prove my credentials (in being un-sporty), I have caught exactly one fish in my entire life.

The recreational landscape of the Bay is all about the shoreline. We have hundreds of miles of it. The wrinkly edge (when it's not impenetrable due to industry or freeways) is a varied landscape for interaction between people and the water. We can imagine the soundscape of this edge - wind rustling sails, birds, water surging over rocks when a large boat passes by.  It's predictable. It's also not as clean as that. There often is a freeway nearby, or any number of sounds. But what about sticking a microphone beneath the water's surface. What does this tell us about the urban, watery edge?



Soundfishing bypasses the usual urban soundscape for an entirely new one, in which motor boats sound like angry hair-dryers, and the propellers of cool old ships produce lo-fi drone music for anybody listening in.


I like environments where it is difficult to hear. Difficult, not because it is loud, but because we are not made for a particular listening environment. When a human ear is underwater, the ear drum does not vibrate the same way that it does in air. The ear barely works under water, so the way we hear is actually through bone conduction. Pressure in water is translated to our skull, which transmits the sound directly to our inner ear.

If my ears are useless, then lend me a microphone. In order to listen to this underwater world, we must augment our hearing. I like that, the opportunity to question how we hear sound and what we might do to hear things differently. So I made a hydrophone with about 15 dollars worth of electronic parts and threw it in the water.

The hydrophone as "bait" , coated in silicone

In water, sound travels four times faster than it does in air. It's a thick medium for sound, which means sound travels well and quite far. It also means certain sounds are not able to move far, such as high frequency sounds. Above a few thousand kilohertz, sound dies off shortly after it is emitted.



My first fishing expedition was in the Oakland shipping channel off the shore of Alameda. I saw a couple people pulling out actual fish. I certainly wouldn't want to be a fish in these waters, not just for the fear of being prey but it is LOUD in there. At one point I was listening to five boats motoring around, plus a jet ski. It just sounds like a bunch of mad screaming lawn mowers and pencil sharpeners under there.

But there are some cool, subtle sounds, and a lot more exploring to be done of the Bay.  Stay tuned.