Category Archives: Acoustics

Getting to an Inexpensive Audio Datalogger

Well, I spent my Saturday morning programming a C# application for Windows Mobile 5 to periodically record audio. I was aiming to set up a data logger using the Raspberry Pi board I’ve got, but I’ve run into enough problems that I decided to look at another approach. The idea is to log acoustic data […]

Raspberry Pi First Run

I checked the UPS tracking number periodically today. My Raspberry Pi was marked as delivered at about 2:30 today. When I got home, I found the package. I still needed to prepare the SD card, so I brought up the RasPi Wiki instructions for SD card setup and went with the Debian Squeeze distribution to […]

Personal Research and the Budget

Diane and I are working on a personal project to put together an acoustic sampling system that could yield information about the activity levels of snapping shrimp. Whitlow Au and his group have done this sort of thing out in the Pacific. Of course, they’ve gotten research funding to do it. We’re looking to do […]

Python and the STFT

I’ve been going through biosonar data and while the SciPy specgram method is serviceable, I was interested in a short-time Fourier transform (STFT) implementation. There are a couple of ad hoc routines on Stack Overflow and the like, but I’ve started off with the Google Code PyTFD module. There are others out there as well, […]

Some Data Analysis and Visualization

As noted here before, I’m working through refreshing archived data, mostly from CD-ROM media. I’ve run into a whole batch of CD-ROM disks that are in good physical condition, but which mostly cannot be read. I’m trying some tools that I’ve seen recommended, but would be open to suggestions. But the whole point of getting […]

The Weekend

I don’t know what other people got up to this weekend, but mine has been pretty well filled with computing projects. I’ve been working with my friend Marc to try to get to the bottom of the Verizon FIOS connection foul-up. We each ran TCPDUMP on our respective machines while making a request that could […]

Multiple Sound Sources in the Bottlenose Dolphin

It’s been a long time coming, but the paper on evidence for multiple sound sources in the bottlenose dolphin appears in the October 15th issue of the Journal of Experimental Marine Biology and Ecology. I’ve been told that the PDF will be freely available soon, hopefully in the next week or so. The abstract is: […]

Cool Acoustics Product: Tern Micro GR4

I occasionally check out the Tern Micro website. They are manufacturers of controllers and expansion boards for embedded applications. Their controller boards use IAPx86 class CPUs and are programmed in C. A few years ago, I had checked with them about whether they had components suitable for a field acoustic recorder, and given the short […]

Plotting a Dolphin Biosonar Click Train

I’ve been busy recently doing up figures for a paper on dolphin biosonar. One of the figures we ended up turning in earlier this week wasn’t exactly as I wanted it, but deadlines don’t wait. I put a lot of hours into trying to find alternative plotting for it, but just hadn’t found the right […]

Listening to Snapping Shrimp

I’m working on setting up a citizen scientist project to document where snapping shrimp (family Alpheidae) are active pre- and post-contamination by the oil spill in the Gulf of Mexico. In this post, I just want to introduce the basic concepts and provide an example sound file. Snapping shrimp comprise a number of species, mostly […]

Beaked Whale Stranding in the Azores

This came across MARMAM just now. Subject: [MARMAM] Six Beaked Whales stranded in Azores (URGENT) From: “marc fernandez” Date: Sat, June 27, 2009 5:47 am Dear Colleagues, I want to report an unusual situation occurred during the last week and a half in São Miguel island, Azores, and ask for help in order to get […]

Acoustics Blooper in NCIS

I saw the NCIS episode “One Shot, One Kill” and noticed a blooper in the show. Maybe that’s not that cool, but this particular blooper requires knowing something about acoustic localization. This is the technology that is being used to let marine mammal researchers place the position of whales who are vocalizing and also lets […]

Sirenian International Goes Sociable

Sirenian International, a manatee conservation and public outreach organization, now has a Facebook group. SI also has a field course in Belize that one can sign up for: Ecology, Behavior & Conservation of Manatees & Dolphins A Unique Field Course in the Drowned Cayes, Belize Host: Caryn Self-Sullivan Type: Education – Class Network: Global Start […]

Biosonar Turns Waspish

Nature (7228, p.361) had notice of an article in Biological Journal of the Linnean Society (96, 82-102, 2009) that demonstrates the use of biosonar in several species of parasitic wasps. These wasps seek out beetle larvae in trees, using hammer-like ends of the antennae to produce sound. So far as I know, this is the […]

Sigh… Another Item for the Wish List

M-Audio has updated its handheld Microtrack solid-state recorder to the Microtrack II. The specs are attractive. It records in stereo to Compact Flash or MicroDisk format cards, in either WAV or MP3 formats. It can record at up to 96 kilosamples/second at 24 bits per sample. It has both 1/4″ and 1/8″ microphone/line inputs, and […]