Microphone for Nocturnal Flight Calls

This is part of the LycoBirds Guide to Recording Nocturnal Flight Calls by David Brown

My microphone is the Old Bird 21c. These microphones are built specifically for this purpose and are sold by Bill Evans from the oldbird.org website. The cost is approximately $300.

Instructions for building your own microphone are also provided on the Old Bird website.

The Old Bird 21c is completely set up already. All you have to do is connect the cables together. I attached my microphone to my roof by simply setting it on a flat area and bungee cording it to an adjacent gutter. This perhaps isn't the best idea because it increases the noise on windy and rainy nights, but it was the easiest way to get it set up quickly and hasn't been enough of an issue to change.

A short cable with XLR connector comes out of bucket. Attached to that is a 100 foot cable with XLR connectors on both ends that feeds inside the house. To avoid permanent changes I just popped out the corner of a window screen, fed it through, then used duct tape to seal the area to keep bugs out.

The XLR connector at the other end plugs into a small black box that has additional electronics inside. This box needs to be near your recorder and near a power outlet.

The black box has a power adapter and a 3.5mm audio jack (short cable included, but of course a different one can be used). The box also has a low-cut filter installed to cut out the rumble of traffic and other low frequencies. Instructions for turning this filter off are included.

The microphone turns on when you plug in the power adapter. Electronics inside the bucket emit 5 tones that the microphone picks up. Each hour a single tone is given again.

Additional information about the microphone and installation can be found in the following videos: