Here’s a list of the stuff I’ve been using to record and analyse bird songs and calls.

Recording

Hardware

I use my iPhone.

It’s usable on its own, but captures a lot of wind and ambient noise, e.g. traffic. With plenty of both the norm in my area, I bought a directional microphone: RØDE VideoMic Me-L

This plugs into the lightning port, and comes with a furry baffle to reduce wind noise.

The next step up would be a hand-held recorder such as these popular models from Olympus or Zoom.

Software

Reording software must be easy to use and must be able to record at high quality in a lossless format! (Guidance on the Web always says ‘WAV’ but FLAC, ALAC etc are fine too).

I use Apple’s built-in Voice Memos app.

  • It can be set to record losslessly and is easy to use.
  • It’s supposed to sync to the Voice Memos app on my Mac, which would be nice but it doesn’t work.
  • It can automatically name files based on location. This feature is inaccurate and awful and must be switched off.

I haven’t explored alternatives in depth yet - I would like to find something that includes metadata such as lat and long, but that might not be out there.

Editing

I have found two easy to use audio editing programs, Audacity and Ocenaudio.

Both allow you to do all of the very basic things I use them for:

  • view waveforms, spectrograms or both together
  • perform basic edits, eg trimming out unwanted noise or copying an interesting section to a new file
  • Normalise, to bring the volume up to a standard level
  • High Pass filter, to get rid of some of the low-frequency background from wind and traffic etc.

I don’t do more processing than this as messing about with noise reduction or trying to use dynamics processing to improve sgnal:noise ratio seems to do more harm than good. The answer is to get a better recording in the first place!

Spectrograms

Audacity and Ocenaudio both give you a spectrogram view of your sound file, and provide (different) tools for modifying the spectrogram display, however I haven’t found an export function for either. One could always take a screen shot.

I’ve found two more specialised programs for spectrogram analysis. Both are designed for people doing complex analysis of sound and include features for preparing spectrogram figures e.g. for inclusion in scientific papers.

Praat is designed for people working with human speech. It has a learning curve but I quickly found I could create pleasing images of spectrograms and export an image file with a bit of fiddling.

Raven is designed for bird song analysis. I have played with it less but it’s perhaps a better choice. There’s a free Lite version. The paid version is pricey but I think anyone who actually needs it is including it in their research grant applications!

There’s a third approach, which is to learn how to create your own spectrograms. Features to do this are ready available for anyone willing to learn some of the basics of R or Python.

For quick-and-dirty images and videos I’ve gone with the latter approach. More on that in the future!