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I am working on my undergrad thesis with geographical variations on parrot vocalizations.I originally designed my study with Audiomoths because I had just gotten some. However, I now realized that although Audiomoths do a good job and give me a clear signal, I don't think it's "clear enough" to measure certain parameters, as the background noise is too loud or the calls are clipped. I was then going to borrow a Rode shotgun mic but it seems to be having issues, recordings have a mid-low frequency buzz which is audible and visible.

I have a Zoom H4n pro recorder, with the gain set at 80, the spectrograms are clear and background noise seems acceptable, there is some clipping but only for a few calls. I'm tempted to just go ahead and use this to record the parrots but at the same time feel it's not a professional choice and my results would be questioned. The only mic option I found in my country is a Boya BY-PVM3000 shotgun mic (no reviews related to birds). My other option would be to order an inexpensive mic online and wait until breeding season starts around October (which I am willing to do if it's the best choice). I'd appreciate any opinions or suggestions on this. Thank you!

Edit: I preformed some tests with my species of interest at a distance of approximately 200m. I selected a few calls of interest with Raven and then averaged the values:

Audiomoth at 32kHZ/32bit and low-med gain.

  • Delta t=0.38s Low freq=1082 Hi=freq 4641 Max freq=2024 SNRquick=15.1 Audiomoth spectrogram different call types

Zoom H4N Pro at 44.1kHz/24bit and 70 (out of 100) gain.

  • Delta t=0.31s Low freq=873 Hi=freq 4419 Max freq=2165 SNRquick=16.9 Zoom spectrogram different call types

Samples from XenoCanto for contrast.

  • Delta t =.26s Low freq=962 Hi freq=4642 Max freq=2749 SNRquick=21 NK XenoCanto RS XenoCanto
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  • $\begingroup$ This question is tricky to answer without knowing: 1) the vocalization frequency of parrots, 2) the [maximal] acoustic sampling frequency of the proposed device, and 3) the dynamic range of the proposed device, in concert with how far away you would like to record. Could you please specify these? $\endgroup$
    – Chloe
    Commented May 2, 2023 at 9:41
  • $\begingroup$ @Chloe thanks for the comment, I edited my question with the specifics, I also included a few spectrograms from my tests. $\endgroup$
    – user1396
    Commented May 11, 2023 at 8:32

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If you have a Zoom H4n and your tests give you clear spectrograms, go ahead and use it. It is not clear to me why this type of recorder is not deemed professional.

The only thing you must make sure is that bandwidth is sufficient, gain settings are such that none or only few calls are saturated, and that you can protocol all parameters, that means NO automatic gain control (AGC).

Edit: with all recorders you should check if you can modify the gain settings. IFAIK, Audiomoth has the option to change the gain. Adjust gain such that signals of interest are not clipped, while background noise is still visible in spectrogram.

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  • $\begingroup$ Yes, the device is fine. I use similar recording devices for similar animals. $\endgroup$
    – Dan Stowell ♦
    Commented May 2, 2023 at 12:38

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