#Sciencedeskdigs: Sound Level Meter

a sound level meter component resembling a computer chip

NPS Photo/M.Reed

We want you close your eyes and picture a National Park. What do you see? Snow-capped mountains, wildflower covered prairies, historic battlefields? Now what do you hear? All parks have sounds associated with them, and thanks to physical scientists like Damon Joyce in the Natural Sounds division, we can study and preserve these unique soundscapes.

What is it?
This is a custom designed sound level meter that I built in collaboration with Colorado State University. This is one component of a unit that we send to different parks in order to record, store, or stream live audio data. The units costs around $150, which is significantly cheaper than the high-end sound meters that can be thousands of dollars. Since these units don’t cost a lot, we can also use them as outreach tools to educate visitors on how we measure sound in parks.

Natural sounds are important for both park visitors and the animals that live there. Visitors want to experience the natural or cultural sounds that are associated with that park and animals use sound to find a mate, food, and avoid being food. Gathering data on all sounds in parks is the first step to preserving natural sounds. Right now these instruments pick up louder noises such as birds, motorcycles, and cars and are being used at parks like Grand Teton, Great Smoky Mountains, Lake Mead, and Bryce Canyon to display vehicle sound levels on a roadside sign.

Describe your workspace in one word:
MacGyver-ed. You'll often find me trying to fix some test unit with scrap pieces of wire and whatever other things I could salvage from a willing electronic host.
a sound level meter unit with several wires and boards
The components that make up the sound level meter unit that is sent to parks.  They are put together and then encased in a weatherproof container.

NPS Photo/M.Reed