<p>Megan,  Hi.  The trigger option within Audiomoth firmware is quite new, so there are probably few people able to comment well on this?</p>
<p>However... the use of amplitude-based triggers within the audible range has a few difficulties.  Within ultrasound it works well, as there is often not that much going on apart from bats and some species of invertebrates, so triggers are only activated when something (i.e. a bat call) occasionally happens.  If you are in an urban area, then low frequency sounds are probably relatively common from planes, trains and autombiles, and you will be triggering fairly continuously.</p>
<p>However again - I note that you are looking at the 30-200 hz super-low band only, so maybe events within that band are fairly rare, and so triggers filtered within that range might work OK - depending on the local soundscape context.</p>
<p>So far, so useless as an answer? It might be down to you to test and provide us all with the results?  Best of luck</p>

CC BY-SA 4.0
2022-07-12T22:30:21.583Z
Thanks Carlos, your answer is actually very helpful! It seems like maybe I should record some baseline data first to see what kind of frequency ranges I'd be dealing with and assess the potential for irrelevant triggers.
Megan Perra
CC BY-SA 4.0
2022-07-11T14:12:15.660Z
2022-07-11T14:12:15.660Z
Carlos Abrahams
<p>I was curious if anyone has used the frequency trigger in <a href="https://www.openacousticdevices.info/audiomoth" rel="noreferrer">AudioMoth</a> and if they found it functioned well? I’m exploring the idea of using it to detect lower frequency anthrophony (30-200 hz) to monitor sound disturbance in an industrial area, and was hoping the trigger might reduce the amount of data that has to be processed by only recording when the sounds of interest are present.  Has anyone had success testing this feature yet? I'm afraid that a lower frequency trigger would get triggered by wind.</p>

<identification><anthropogenic-noise><frequency-response><audiomoth><monitoring>
Anyone have experience using frequency trigger in AudioMoth?
# Anyone have experience using frequency trigger in AudioMoth?

(Asked by: username_0 on 2022-07-08)

I was curious if anyone has used the frequency trigger in [AudioMoth](https://www.openacousticdevices.info/audiomoth) and if they found it functioned well? I’m exploring the idea of using it to detect lower frequency anthrophony (30-200 hz) to monitor sound disturbance in an industrial area, and was hoping the trigger might reduce the amount of data that has to be processed by only recording when the sounds of interest are present. Has anyone had success testing this feature yet? I'm afraid that a lower frequency trigger would get triggered by wind.

**Tags:** identification, anthropogenic-noise, frequency-response, audiomoth, monitoring


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## 1 answers

### Answer by username_1 on 2022-07-11. Score: 1

username_0, Hi. The trigger option within Audiomoth firmware is quite new, so there are probably few people able to comment well on this?

However... the use of amplitude-based triggers within the audible range has a few difficulties. Within ultrasound it works well, as there is often not that much going on apart from bats and some species of invertebrates, so triggers are only activated when something (i.e. a bat call) occasionally happens. If you are in an urban area, then low frequency sounds are probably relatively common from planes, trains and autombiles, and you will be triggering fairly continuously.

However again - I note that you are looking at the 30-200 hz super-low band only, so maybe events within that band are fairly rare, and so triggers filtered within that range might work OK - depending on the local soundscape context.

So far, so useless as an answer? It might be down to you to test and provide us all with the results? Best of luck

> **Comments:**
> **username_0**: Thanks username_1, your answer is actually very helpful! It seems like maybe I should record some baseline data first to see what kind of frequency ranges I'd be dealing with and assess the potential for irrelevant triggers.  

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