For how crucial whales have been for humanity, from their harvest for meat and oil to their future use of saving the world from a space probe, humans knew very little about them until surprisingly recently. Most people, even in Herman Melville’s time, considered whales to be fish, and it wasn’t until humans went looking for submarines in the mid-1900s that we started to understand the complexities of their songs. And you don’t have to be a submarine pilot to listen now, either; all you need is something like these homemade hydraphones.
This project was done as part of a workshop in Indonesia, and it only takes a few hours to build. It’s based on a piezo microphone enclosed in a small case. A standard 3.5 mm audio cable runs into the enclosure and powers a preamp using a transistor and two resistors. With the piezo microphone and amplifier installed in this case, the case itself is waterproofed with a spray and allowed to dry. When doing this build in places where Plasti-Dip is available, it was found to be a more reliable and faster waterproofing method. Either way, with the waterproofing layer finished, it’s ready to toss into a body of water to listen for various sounds.
Some further instructions beyond construction demonstrate how to use these to capture stereo sounds, using two microphones connected to a stereo jack. The creators also took a setup connected to a Raspberry Pi offshore to a floating dock and installed a set permanently, streaming live audio wirelessly back to the mainland for easy listening, review, and analysis. There are other ways of interacting with the ocean using sound as well, like this project, which looks to open-source a sonar system.
Thanks to [deathbots] for the tip!
Love the Star Trek reference. I am lucky enough to live in Hawai’i, and this time of year the humpback whales are arriving for their winter vacation. At our favorite local swimming spot, if you swim out past the the noisy surf break, then dive down about 10 ft or more, you can hear the whales singing in the distance. It is a lovely and unforgettable experience :)
Didn’t give us a Dishonored reference though.
Nuke the whales!
Also:
They are about as smart as pigs.
fMRI explains the extra grey matter.
Sonar processing.
The dude that boldly asserted they were as smart as humans was on LSD at the time.
Now it’s just unquestioned hippie derp.
Imagine no hippies!
User name checks out – you are funny ! If you’re going to assert that someone did fMRI on a whale, at least give us link.
It was done. Wasn’t much gray matter to account for, but some curious orange hair on the skin.
I made a few types of piezo hydrophones, but the end result was not as good as just an electret in a plastic bag (for humanly audible sounds). still, it is fun building them.
Not a surprise. A piezo has a very high impedance, you must at least use a J-FET stage to be able to use it.
This is a good and inexpensive project for making a hydrophone. I like that they incorporated a FET buffer that will work with most recorders.
When you really get hooked on underwater sounds and want to upgrade, consider building a set of these:
https://www.instructables.com/The-Gladys-Hydrophone/