Pages

Sunday, October 23, 2011

Serious Bat Call Analysis Software

Well, Folks, judging by some of the recent e-mails I've received - It looks like I'm going to need to focus my attention on bat call analysis software. I was actually planning to, but was going to wait until at least mid-Winter. As, I fully expected to have FUN recording quite a few more bats, especially Red Bats! And, perhaps even another "surprise" species or two?...

Let's see here - The software packages whose names kept "popping up" (mentioned by interested readers) so far, have been: BatSound, and SonoBat
Both are regarded as excellent software programs for Professionals, as well as dedicated Hobbyists. As with most things, the really good stuff isn't cheap.

In any case, after some recent correspondence with other Hobbyists - I'm beginning to realize that it is time for me to consider investing in a good analysis program.
Also, there are some interesting Free applications available, for Bio-acoustic analysis. I may look into a couple of them, test, and report my findings.

For the most part, I use Audacity (which is free) and Bat Scan, which is very reasonably-priced software, from BatBox, Ltd. in the UK.

While I'm on the subject...
I've been meaning to post some of my thoughts and ideas, on good activities for bat hobbyists; for the "dead of Winter" (as in, January, mainly). For the month of January, in the Northeastern United States for instance: We have pretty much zero bat activity : (
So, it's a good time to focus our attention on things like:

* Becoming well acquainted with, and experimenting with, bat call analysis software.
* Going through (sorting out) all of the recordings collected from earlier in the year.
* And, of course: Analyzing, organizing and archiving the recordings (and sonograms, etc.)

Happy bat detecting!

Thursday, October 20, 2011

Added A Section For Bat Organizations

Just a quick post, to let you know, that I've added a place (on the right-hand side of the main page) for Links to Bat organizations. I received a note from a reader recently, who made me aware of this organization; and their upcoming events: North American Society For Bat Research I've still got a lot more to add. There are so many great Bat Conservation Organizations...all over the world...
{Also, for those who might be interested, this blog (that is, Bat Detector Reviews) gets approximately 1,530 Visitors per month.}

Here is a site (from Sweden) that I've been getting some traffic from recently, so I thought I'd post it up here (for those who speak Swedish) - And for those (who, like me) enjoy poking around foreign sites: Here's the link I usually "click around" on: http://www.chiroptera.se/tips.html And, here is the Main page: chiroptera.se
Well, no, it's not very easy when you don't know the language...and when BabelFish (and other) services cannot translate for you... But: If it has anything to do with bat detecting, then I'm there!

Until next time...

Wednesday, October 19, 2011

Recent Visit To Bartow Pell Mansion - And, Other Miscellaneous Things...

What follows, is the "debriefing" of my recent visit to Bartow Pell Mansion:
Unfortunately, there weren't many bats recorded: We are getting pretty close, to the end of the season for the majority of our local bats here. I'm still sorting through the recordings made on The Griffin, so there is a chance that I did pick up (an unseen) bat... If so, I will add the sonogram(s) to this post.
-But- I did end up recording a nice assortment of singing insects. That was great!
Yes, one of my other major hobbies is recording singing insects - But - In the interest of those who are interested only in bats; I've kept the subject (and recordings) of insects, out of this blog. I'm sure most Folks prefer it that way. The subject of recording singing insects would definitely need it's own blog!

I can tell you, that The Batbox Griffin and the SSF2 BAT were a pleasure to use in the field!  Dodotronic's Ultramic200K was great, too! (set up on a tiny tripod)

For now, you can have a look at a short video I took of the area. This is behind the mansion. You can hear the water fountain (pond) in the background, among the sounds of singing insects:

video

Remember, The Griffin Review isn't finished yet...and the SSF2 BAT Review will be coming up soon...

Happy bat detecting!

Thursday, October 13, 2011

The Next Detector To Be Reviewed: The SSF BAT2 Detector!

The next bat detector I'll be reviewing, will be The SSF BAT2. This detector is really neat!

Here is a quick snapshot I took, while on the trip to Bartow Pell Mansion. Pictured, from left to right, are: The SSF BAT2, The Batscanner from Elekon and the Griffin from BatBox (I apologize for the poor image quality):


Happy bat detecting!

Sunday, October 9, 2011

Future Site Of Bat Detecting Adventure - Bartow Pell Mansion

I haven't been on a bat detecting field trip in quite a while. This will be the awesome place I'll be visiting:


Bartow Pell Mansion

It is my favorite place to go Birding, and to photograph wildlife; during the day. It is also a very safe place (when it comes to 2-legged "predators"), which is also a big plus. I like to be able to focus all my attention on the fauna & wildlife while walking through the woods - Not having to be concerned with my own safety as well.
So, I requested (and was graciously granted) permission to visit the premises at night. I'm bringing some of the latest bat detectors that are currently "on the test bench". There's nothing like bringing new, cutting edge bat detectors on an "expedition" like this!

Among the instruments I'll be bringing are:

The Griffin, from BatBox Ltd.

The SSF2 BAT2 from BUND

The Ultramic200K from Dodotronic

The D240X from Pettersson Elektronik

A full "Debreifing" is forthcoming...

Review: The BatBox Griffin From BatBox, Ltd. (UK) Part 3 Of 3

Review: The BatBox Griffin Part 3 Of 3

Of course, as many of you are aware, The Griffin from BatBox experienced some delays prior to it's actual release. This was a disappointment to many bat enthusiasts, and especially to bat working Professionals. Only because many Pros were very anxious to try The Griffin!
When I log my bat recordings, I generally like to record:
The location, the date & time, and the weather conditions; including temperature and the current wind speed. One of the reasons for this: Is that quite a few texts & books written on the subject of Bats, mention the importance, and impact of wind on the flight behavior of bats. With The Griffin, time & temperature are recorded for you.



Above: The unit is in heterodyne mode (indicated by the 'HET' at the top of the screen)

In a recent e-mail I received, someone inquired as to the sample rate of this unit. The Griffin uses a sample rate of 705.6 kHz to accomplish it's time expansion detecting. But, makes the actual recording at a sample rate of 44.1 kHz (16-bit PCM).
As mentioned, in Part 2 of this review: There are many great updates and changes planned for The BatBox Griffin - As soon as these additional improvements are made, they will be described here, in detail.

*Update* 11/11/2011 *

The latest news I'd like to share, regarding The Griffin; is that I've gone ahead and updated the firmware on the system. Twice. In order to get the system up to the latest firmware version (V.20).
These firmware packages can be downloaded from the BatBox - Griffin Web page.

Very easy, and straightforward; each downloaded (zipped) package includes a Word (Text) document, which guides you through the process.

As with many computer-based instruments (as well as many PC systems themselves) the instrument must be updated in a progressive order. So, to get to Ver. 20, you must first successfully update to Ver. 18. (Ver. 19 did exist, but was for testing purposes only).
So, firmware version 18 was unzipped, and installed as per BatBox's instructions. The firmware upgrade process has The Griffin behaving just like a PC. The removable memory card is used to perform the upgrade. The process was finished in less than the 10 minutes stated in the accompanying instructions.

After completion, the unit reboots itself - The screen displays: A blinking cursor, followed by "Upgrade finished", and "Starting Griffin"
Although I knew that I'd be following up, right away, with the next firmware update: I wanted to do a bit of testing, following this upgrade. - As with most firmware updates - The issues addressed, improved features, and/or changes are listed by the manufacturer. What I found, in addition to these - was that the unit was even more sensitive than before! Awesome!
Next, was firmware version 20. All went smoothly, as above. This time, what I found, in addition - was that the unit was more responsive to input (such as pressing buttons, making selections, launching modes, etc.).
I was pleasantly surprised, and well-pleased. The Griffin from BatBox Ltd. is truly a brilliant machine.

Happy bat detecting!

Thursday, October 6, 2011

Review: The BatBox Griffin, From BatBox, Ltd. (UK) Part 2 Of 3

Review: The BatBox Griffin Part 2 Of 3

Aside from the fact, that that The Griffin is an advanced instrument for bat detecting - I feel compelled to mention, that it is somewhat of a conversation piece as well! You may think that I've "lost it" this time...but, it's true! And, I just had to mention it - Although it may seem trivial to some...I find it to be a nice advantage.
You take this beautiful, blue display for instance:



It's a back-lit, LCD/negative blue display (128x64). And, it's simply a joy to behold, most of my pictures do not do it justice - Complete with very cute splash screens at boot-up and shut down! - I do have pics of said cute splash screens, but won't post them up. They will be a neat surprise to new owners of this unit.
Well, these are the kinds of things that even the layperson (even one who has no interest in bat detectors) can appreciate.

OK, this is a serious bat detector - So let's get back to a serious review...

In general, the layout on The Griffin, is very straight-forward and simple. I like the front-mounted, diffused, LED indicator. It's a bi-color LED, and provides a soft, intermittent flashing: Green: to indicate Normal/On operation. And Red: to inform the user that a program has been stored, and will execute. It serves to assure the user, that although the unit is in a powered-off state; it will be turning on/recording later.

Below, is an example of what a typical triggered recording looks like; in Audacity (free program). In this example, upon first opening the file, Audacity "decided" to use 44.1kHz & 32-bit. The machine actually makes the recording at PCM 16-bit 44.1kHz quality. Which, as many of you are aware, is substantial. You can see the dialog box where I chose to specify 70560, as the sampling rate:



By specifying 70560, you are reducing the original 705.6kHz sample rate of the recording by a factor of 10.
This is simply one random experiment. There are almost countless combinations, and opportunities to experiment further. The example above, contains calls from my local Katydids (@ ~40+ Meters distant) and a couple of bat calls.

Below, is an example of what a single, isolated bat call looks like, when using Audacity:




This is an example of what Katydid calls & Bat calls look like, when using Audacity -
As far as I can tell, (and after listening to the recording numerous times) the first 2 are insect calls, the rest are Bat calls):



Here is a sample section, of the recording above, using BatScan Ver. 9 software (from BatBox, Ltd.):




The Time Expansion option was selected in Batscan, when analyzing the file above. This particular example appears to be of a bat that was recorded at a fair distance. I will be posting a few more examples in the future.

Here is a look at what the additional, detailed Info, (in raw format) that was recorded by The Griffin:


<batbox_recording>
<batbox_file_version>0.1.1</batbox_file_version>
<sample_rate>44100</sample_rate>
<record_time>00h 00m 48.02s</record_time>
<sample_count>2117632</sample_count>
<file_size_bytes>4235308</file_size_bytes>
<begin_record>
<date>03-Sep-11</date>
<time>17:12:46</time>
<degrees_c>20.000000</degrees_c>
<light>4.701802</light>
<endtag>0</endtag>
</begin_record>
<end_record>
<date>03-Sep-11</date>
<time>17:12:51</time>
<degrees_c>20.000000</degrees_c>
<light>4.701802</light>
<endtag>0</endtag>
</end_record>
</batbox_recording>

This information, can be viewed in a much neater format, by using an application that reads .HTML or .XML files.

And this is the other data file, that is automatically created, with each recorded event:
This was simply opened with Notepad, but can opened using various text editors (The data looks the same when using MS Word to view):


date=03-Sep-11
time=17:12:46
sample_rate=705600
temperature(C)=20.000000
light=4.701802
rec_time=00h 00m 3.00s

I find it to be a nice plus. And, for those who are really into spreadsheets, applications and databases: There are numerous possibilities.
These are all just some minor details, which you will discover on your own. Advanced (experienced) users of bat detectors, will be able to just "take the ball and run with it" (as they say).

Suffice it to say, that programming the unit (for automated operation, etc.) is not difficult in the least.
Which reminds me: I've found it easy to become accustomed to using The Griffin. After only reading through the User Manual once. This is not the case with all advanced bat detectors, by the way. With other high-end detectors, you need to practically study the manual...So, I believe this is important to note.
As far as one-handed operation: Although it is possible, I much rather use both hands when operating the unit.

I happen to like the way it instantly switches (or toggles) between each of it's operating modes - With a press of the 'H' key. Each push will scroll through: Heterodyne, Frequency Division, Binaural, and Silent (recording) mode.
Another advantage, is that your recording time, is only limited by the size of your CF memory card. It's basically the kind of instrument you can take on a bat survey or exploration, without the need for any additional equipment. This is not to say that you cannot bring additional recorders, etc. if you so choose. As some users, may want to do just that. The usual (lossless) direct-to-card recording is not the only way to record. There happens to be a perfectly serviceable Headphone Jack provided. This can be used for recording either a heterodyne, frequency division, or Binaural output - to any suitable recorder.

For example: I tried a few further tests myself, this evening. And the results were great, just as I expected - Like having 3 different detectors available, all in the same box.
So you see, you do get a lot of bat detector for your money. If your an advanced Hobbyist: You'll have enough variations to experiment with (to keep you busy for a while).

But again, the point of this system; one of it's main advantages, is that you can just grab it and go. Battery life is great - A set of 4 AA-size, fully charged (NimH), or fresh alkaline batteries - will last you all evening, and well into the dawn hours. This has always been the case for me (regardless of the type of batteries I've employed).
I have come to realize, that an important facet, of the overall value of a bat detector - Is how easy it is to use. A bat detecting system that is easy to set-up and use, is likely to be one that you use more often. As opposed, to one that needs a bit more set-up time, accessories, and sometimes: A bit of a hassle.
In other words: How is the detector for daily use? Well, at this price-point; you get an advanced system that also happens to be very easy to use. When you become familiar with it: It can go from 'Off' to 'Listening' (recording) in under ~20 seconds.

Things I like: 
The display! Plus it's ability to automatically or manually (10 levels) adjust LCD brightness.
The external power option - Makes stationary recording free of the hassle of battery changing.
The internal (electronic) design of the unit - Such as limiting the AGC to be employed for speaker or headphones only.

Things I don't like: 
I would like to see a slightly more protected microphone: Something to provide a bit of protection of the mic element. This appears to be the only (external) design weakness I could find. I realize I may be "nit-picking" here... Let me be a bit more clear on this: The housing itself is OK, and in general, seems to be sturdy enough. What I'd like to see, for example - Would be perhaps a fine (translucent), or black nylon (fibrous) material in front of the element. I think I would just feel a bit better. The reason for this, is - The Griffin is such a high-end and capable system, I would prefer to have the "business end" of it kept safe.

More to follow - I hope to add more images to this post in the future (sonograms, etc.)

Stay-tuned for the upcoming Part 3 Of 3 of this review...
*Note* Part 3 of this review, will cover all of the latest updates and new features. As I type this, new firmware-based features are in the works for this unit! There will be quite a few very interesting updates and improvements made to The Griffin, in the very near future...

Link to Part 3 Of 3

Until then, Happy bat detecting!