Review of The SM2BAT System From Wildlife Acoustics Part 3 Of 3

Review of The SM2BAT system from Wildlife Acoustics Part 3 Of 3

Here is where I would like to share some miscellaneous sonograms and screenshots.

My usual workflow, is to:
Remove the SD card from the SM2 and check it (on PC) for recordings from the night before.
I select one WAC file at a time - Working from the largest (WAC) file to the smallest.
Convert the WAC file to WAV format using the (free) WAC2WAV converter application. The WAC2WAV software allows for a few options & variables. One of the options, is to choose (check-box to tick) is the 'Divide Output By 10' which I normally use. This provides you with wav files that are slowed down by a factor of 10. So, for example, if you were to analyze the files later with BatBox's Batscan SW- You don't have to select anything for 'Frequency and Time Conversion' - It should be left 'Off' which is the default.
Typically, the conversion will produce a lot of individual files. So, I go through each of them, using the same method above.
Recently, I've been using Audacity, to open each Wav file. It's very convenient, because it gives you a visual representation of the audio file very quickly. You can see if there are any bat calls, mixed in among the insect calls. My trees are all occupied by Katydids, etc. - I'm not complaining ('cause I like recording them also!). But, when you're focusing on bat recordings, you have to "weed them out" of course.
Since it's now mid-Summer, I usually find an abundance of my triggered recordings to be entirely of Katydids (for instance). And, I simply delete those and check the next file.
Again, using Audacity (or another audio app) which displays the 'Project' (audio track) conveniently:
What I do, is 'Select All', Amplify' and look at the recording closely, to find any area that looks like a bat call.
I also find myself listening to certain areas of the recording sometimes, just to be sure.

Adhering to the chronological order of a typical workflow, we have:
A typical wav recording (for me), displayed in Audacity:

The above shows a recording with nothing but a Katydid calling. This gives you an idea of what a recording without bats on it looks like.
I've also found, that if you're in a hurry: You can open multiple (wav) files at the same time; and just glance at each one (before closing/deleting) and you can see the bat calls (if they are present) right away. Without even having to 'Select All' and 'Amplify' for instance. It all depends on how much time you have.

This next image, below - gives you an idea of what a recording with bats looks like:

The bat calls, are represented by the "long spikes" on the right-hand-side of the spectrogram. So, as you can see, it's very easy to tell which recordings picked up bat calls - And, which didn't.
Most times, I like to select the area containing bat calls; and cut/paste/save into a new wav file. Which would look like this:

And then, you can look at/analyze the (wav) file, using the application of your choosing. Such as BatBox's Batscan software. Which will produce a sonogram like this quite easily:

BatScan just happens to be the application I go to (these days) - But again, any suitable app of your choosing may be used. For instance, the image above was made quickly, using just the default settings. But, it can be: Enlarged/zoomed-in on, to create an even more prominent "hockey stick" look to the calls.
The kHz settings can be changed, for a more accurate display and analysis.
And, (for a quick "trick") if you do select 'Time Expansion' it will automatically produce a more accurate analysis - Where you can see the calls were actually made between 40-50kHz (Big Brown Bats typically echo-locate between 25-51kHz) see below:

In the above example, you can also see a few Katydid chirps, on the lower left.
The recordings produced, using the SM2BAT are very high-quality. The 192kHz sampling rate is very nice - Crisp & clear. My next post(s) will feature some audio files you may listen to, made by the SM2BAT. And, probably some made by the Pettersson D240X; since I am still very fond of the TE recordings produced by that unit as well.
I hope that you've found this (3-Part) review of the SM2BAT informative (and hopefully, interesting as well).

Happy bat detecting!

Review of The SM2BAT System From Wildlife Acoustics Part 2 Of 3

Review of The SM2BAT system from Wildlife Acoustics Part 2 Of 3

The SM2BAT happens to be the approximate size of other comparable unattended recording solutions. In fact, it is a bit smaller than some. It is easily portable, fitting one (along with accessories, etc.) into a backpack is effortless. Without batteries installed, the unit is very light. In fact, you could probably fit 2-3 units in a backpack (depending on the size of the backpack).

The layout of the unit is nice and simple. The SM2 platform features a large LCD display, several jumpers for setting filtering parameters, and a green LED (for status indication). Sensitivity and filtering are fully adjustable, across the spectrum of the unit's abilities.

The fact is, that once you've read the User Manual(s); and become familiar with operation of the unit - You'll probably find your bat recording becoming so automated; that you'll become lazy! Especially, for those of us who are used to the typical set-ups required for overnight bat recording. In most cases, this consists of:

Standard check of the detector - Battery condition, and any other settings
Standard check of the recorder - Same as above
Locating your audio cable - For connecting the two
Masking (adhesive) tape, etc. for temporary mounting 

Once the SM2BAT is set-up, you can let it go for a few days, a week, or more! And, the unit will diligently record bats, every evening - From sunset to sunrise. So, you can see how easily one can become "lazy".
Click Here to see a graphical representation of the unit's specifications.

OK! On to some more good stuff!

Among the features I like:
The fact that the unit records unadulterated sound, in 192kHz, is great!
The nice selection of audio filtering combinations available. There are lots of options selectable from the jumpers. Below, is a pic of how the unit's jumpers were set at the end of my testing:

Over the testing period, they were slowly migrated, from left to right : )

The fact that the unit can be used as a "Set-and-forget" recorder (for up to 9 days, in any case) is a plus.
The unit is very economical; especially when compared to the similar systems that are currently available.
If you have a quick look at the Comparison Chart, on the Wildlife Acoustics site, you'll see what I mean.
The SongScope software, from Wildlife Acoustics is very versatile; and produces nice-looking (and informative) sonograms.

With the great help/suggestions and support I received from the Folks at Wildlife Acoustics, I ended up with a diverse collection of recordings. The nice thing about it, is that I was able to test a lot of different variations of settings. In a short period of time. You can basically go either way, in your approach to the use of this system: You may choose to rely mostly on the default settings - And take a more simple approach (which is exactly what I did in the beginning of the test period). Or, you may be the type who enjoys tinkering & experimenting. In which case, you'll find no shortage of combinations/settings available to you.

Among the features that I'm not crazy about:
Obviously, one of the drawbacks, is that it cannot be used as you would a typical hand-held bat detector. You can't just grab it and go, on your way out to the woods, or to attend a Bat Walk.
I also wish there was a way to insert and remove the SD cards a bit more easily - Instead of having to remove one of the D-cell batteries each time.

The additional offering of the free, WAC2WAV software - Which is of course, as the name implies: For converting the propriety Wac files into universally used Wav files - Could be placed in both the 'Like' and 'Dislike' category. Likes would be: That it is free, and very versatile. I must confess, that it does offer some features that I find fascinating. Such as systematic removal of noise - In the form of separate Noise Files that are automatically created. As well as a few other neat little options.
But, at the same time, the Dislike would be: The fact that it is needed in the first place!

There is still the matter of providing sonograms, and possibly some recordings; produced by the SM2BAT. The fact that my original hard drive is (temporarily) inaccessible prevents me from posting them easily.
So, I'd rather just go ahead and extend this review a bit: Stay tuned for Part 3 of this Review...

In conclusion, I have a feeling that I'll be writing some more posts demonstrating the abilities of The SM2BAT Platform soon. In addition to the final installment of this review (AKA Part 3). I may be "re-visiting" this unit, and the Pettersson D240X in future posts. Since at this time, I consider both of them to be very impressive.

Click here for Part 3 Of 3 of this review

Happy bat detecting!

Review: The SM2BAT From Wildlife Acoustics - Part 1 Of 3

Review of The SM2BAT system from Wildlife Acoustics Part 1 Of 3

In this first Part of the review, I will be focusing on the main attributes and features of the SM2BAT. The second Part will present lots of great stuff! Such as: Impressions of performance, summary of typical workflow, and a synopsis of how it compares to other ultrasound recording devices - Sensitivity and quality of sound recordings. And, any other stuff I'm able to share! Part 3 Of 3 will provide: Sonograms and sound recordings of bat passes.

To begin with, there are a few features that make this bat detecting system desirable:

* It is particularly well-suited for unattended monitoring/recording of bat activity (it's proven to be excellent for my nightly recordings).
* It is capable of recording many bat passes, for up to 9 nights! directly onto multiple (up to 4) SD cards.
* It's very easy to use, and no PC is needed for the set-up, or actual recording.

There's something else that I must point out, it is the Customer Service/Support aspect of Wildlife Acoustics: In a nutshell, their Technical Support is second to none. That is not to say that other manufacturers of (high-end/top-of-the-range) bat detectors are lacking in this department - They clearly aren't - Certainly not any of the ones that I've dealt with (so far, anyway).
It's just that, in this case, any questions or issues that one may have about their products are answered almost immediately. Their Customer Support is lightning fast! Questions sent via e-mail or left on voice-mail are responded to in moments. And, always with clear & concise information. Usually followed by a follow-up e-mail as well.
How do I know this?

OK, First a confession: I did read both of the included Manuals...Just not very thoroughly - Yes, shame on me...I was very anxious to see how well the SM2 would record bats, so I basically just skimmed over the User Manual...So as a result, I was unclear in the proper operation of the unit, or the most efficient way to post-process it's recordings. So, I ended up having quite a few questions and minor issues. All of which can be classified under 'Operator error' (by the way). As we used to say when I was a Service Technician (many moons ago).

Well, the point of all this, is that I came to discover just how quickly and politely all inquires are responded to. So, potential buyers can rest assured. Wildlife Acoustics definitely excels at customer support!

Another neat attribute of the SM2BAT I like, is how the microphone units are protected.  Using a well-secured, dark gray foam. In the printed materials provided, Wildlife Acoustics explains just how waterproof their SM2 Platforms are. And also explains best practices, and tips for outdoor deployment. I have not used the SM2BAT in inclement weather. As I'm always reluctant to do so (with any ultrasonic recorder).

The SM2 has been blessed with great pick-up range. There is a PCB mounted, 3.5mm earphone jack located inside the SM2 box. This is provided so that one can listen to the sound input while recording; this may be used for live monitoring, to check the status of microphone(s), perform test recordings, etc.
Just plug a pair of earphones/headphones into the 3.5mm jack, and listen for yourself -You'll notice that the omni-directional microphone is picking up everything! Very clearly, I might add. Of course, thresholds/triggers need to be set...

- To open the SM2BAT, you may use either an appropriately sized Flat-head screwdriver, or medium sized Phillips-head (which is what I prefer).
The unit can be permanently mounted to a flat surface (or, a relatively large tree) using the 4 built-in screw holes.
With the top cover screwed back on, in preparation for mounting/deployment - The green LED light will be visible to you, via a built-in diffuser. So that you can get feedback before, during, and after the unit is mounted:
- A steady, repeated blinking: Indicates the unit has started it's scheduled recording. This informs you that the system is awake, and is actively monitoring.

Using the downloaded Song Scope software, available for a 14-day trial period Here You can analyze the data in Wildlife Acoustics' proprietary WAC format. Or, use their free WAC2WAV converter utility. It's really neat! See a screenshot below:

Keep in mind, that the installation and configuration of the SM2BAT is an easy process. But, the (very nice) Folks at Wildlife Acoustics were kind enough to configure my loaner unit, so that it was all ready to go!
What this means, is that they configured the unit to begin recording at sunset; and stop at dawn.
Just install batteries - 4 D cells (Energizer brand recommended), a Class 4 SD memory card, and you're done. 
Some of the other main features, located "under the hood" are: The LCD display - Which is easy to read, and will help you set all device options.
Among the main things you might want to do are:
- Set the Record Start and Stop times, set the internal clock.
- Change jumper settings for advanced filter settings
- Modify the trigger schemes
- Adjust Sensitivity values which you can use to fine-tune the level for the triggering.
 And quite a few other things.

Of course, after a brief phone conversation with one of the Gentlemen at Wildlife Acoustics - I understood everything very clearly. I had quickly learned how their proprietary WAC files work, and how to manipulate them, etc. - And it's been nothing but fun ever since! I've got lots of recorded bat calls to listen to, and create various sonograms with...So I'll be signing off for now.

Click here for Part 2 Of 3 of this review

Happy bat detecting!

The SM2BAT from Wildlife Acoustics

I have recently took delivery of the latest SM2BAT recording platform, from Wildlife Acoustics. The Folks there were nice enough to loan me a unit for a few weeks; so that I can test and review it.
I have been interested in the SM2BAT, and Wildlife Acoustics' software since early 2009 - As evidenced by my own "computer records". I think it just goes to show you, what an amazing product it is. It's not easy to keep me interested in something for over 3 years!
Well the unit arrived just the other day. And so far, all of my usual preliminary tests are producing very nice results. I like the fact, that in it's most basic option package (1 microphone) you get a very capable, professional bio-monitoring device. You start out with it, as a mono recorder. And that is fine with me! But, you may purchase an additional microphone, to make it a 2-channel recorder. More on that subject later...
I like the design, the layout, and the way it records ultrasounds. I can already tell, that it is a selective HF recorder..
The Song Scope software is also robust, effective, and packed with features. There is a lot more to report - but, this is just a quick "heads-up" for now. To let you know that a full, detailed test report and review will follow soon.

Happy bat detecting!

Just something I came across while surfing the Web...

While surfing the Web, for additional research data on bats - I found a certain scientific research paper; that was written, using the Big Brown Bat as the test species. The link to the PDF, etc. really isn't important. I wouldn't want to "single it out" or anything anyway. And, in any case, the data is far too detailed to be of interest to the average bat enthusiast.
But, one of the pieces of equipment used, was this company.
It appears the equipment is no longer available, but at the time it was called the IOtech WaveBook/516E.

In addition to this ridiculously expensive piece of equipment, were equally expensive microphones.

Frankly I just think that it is really excessive, and ridiculous. There are plenty of manufacturers today, that offer excellent equipment - With equal or better capabilities.
With far less complicated interfaces/software; and for far less money. I believe both hobbyists and Researchers are very fortunate today, to have many bat recording solutions that are essentially "Plug & Play"

Here are some that come to mind: 

Pettersson's D240X - D240X

Wildlife Acoustics' SM2BAT - SM2BAT

Binary Acoustics' FR125/AR125 -  FR125/AR125

Animal Sound Labs' LunaBat DFR-1 - LunaBat DFR-1 

In the meantime, I've gotta tell ya, I do my best, not to fall in love with the bat detectors that I review... : )   But, this D240X from Pettersson is a real beauty! Be sure to read my recent review of it, on this Blog!

And, finally - Here are 2 sonograms I made, using Raven Lite; representing it's Time-Expansion capabilities:

 

I'll post more sonograms (and sounds) in the near future.