[mou] Digital Voice Recorder

[Larry Sirvio]

I've been trying to use an Olympus VN 240 PC to record bird songs. The only
purpose I have is to aid in bird id. Therefore I don't want to carry a large
device. The recorder works ok if the bird is close and the frequency is not
too high. I have tested it from 3000 Hz to 10000 Hz. It only reproduces well
up to about 3500 Hz.
Thanks to Julian Sellers I now understand that the "sampling rate" of the
device is important as is the frequency sensitivity of the microphone.
I found out that the VN 240 PC has a sampling rate of 22000 by looking at
the properties of the wav file that it generated. So, in theory, I should
have been able to record up to 10000 Hz.
I don't know why this didn't work.

I also did the frequency test on an IPOD (4th generation) with a Griffin
I-Talk attached. This attachment has a microphone and small speakers.
Unfortunately, it has a sampling rate of 8000 so it was even worse than the
recorder. It can record only to 4000Hz

I also read the Yahoo - Birding Peru list. Someone there had suggested that
she had thought to buy an Olympus WS-100 voice recorder to use for bird id.
I checked their website and found that it has a sampling rate of 44,000/sec.

I bought the WS-100  this morning and tested it. It reproduced all
frequencies up to 10000 Hz.
Sampling rate was indeed 44,000. So it's a keeper for me.

The downside for some might be that they created WMA files which can't be
modified by audio software. This isn't a problem if you can convert wma to
wav (non-compressed). The  audio allows you to amplify, deamplify or cut out
parts of the recorded file.

The other issue I have with the recorder is that the batter cover can open
too easily - I'm sure it's going to open some day out in the field. I may
have to tape it shut.

I still haven't tested it on yellow warblers. That's next. If it can do
yellow warblers then it can do anything.

Larry S