The New Howl - A Demonstration of Sasquatch Vocal Range and Lingual Dexterity

On various websites around the Internet witness reports have described loud vocalizations that were initially mistaken for a siren due to the sheer volume and tone of the call. But as the vocals played out, most witnesses come to realize they are listening to an organic sound, and not something mechanically generated. Until recently, few recordings existed to demonstrate that characteristic however, beyond those of John Andrews and Darrold Smith. Fortunately, some new examples of "horn-like" or siren-like vocals are being captured around the country in such diverse locations as Washington, West Virginia, Kentucky, Virginia and Mississippi.

This amazing clip of a loud vocalizer was captured by "Jolie" at 3:41 a.m. on February 10, 2009, outside of Hattiesburg, Mississippi. To protect Jolie's privacy we are leaving out her last name. To the casual listener the clip sounds like a bizarre mechanical cacophony, almost like hydraulic machinery under stress. But when we put on the head phones, pay close attention, and scrutinize the spectrogram of this recording, several telltale characteristics emerge including falsetto notes, abrupt pitch changes, attenuated fundamental frequencies and integrated wood knocks.

The metallic sounds of the higher notes in this clip have a brassy tone, almost horn-like. This unique call is difficult for humans to replicate organically and is not commonly known to be produced by other North American mammals. The evidence that sasquatch are capable of such uniquely cryptic vocals are another intriguing element of study in the realm of this poorly understood creature.

This is not the first time these mechanical/metallic tones have been captured, but this is one of the clearest examples that also contains other important sasquatch indicators. It is recordings such as this that help us understand descriptions from witnesses, such as the metallic "ping" vocal reported in this BFRO report: "Hunter remembers his lengthy daylight sighting through binoculars near Dora". With time, more of these vocals will emerge and be added to the growing lexicon of sasquatch vocalizations.

Post-Processing Audio Files with Audacity

Almost two years ago I wrote a post titled "Using Audacity to Get The Most Out of Your Recordings" with the intent of passing along useful information to other audio researchers interested in getting the most from their field recordings. In the time since that post I've refined my techniques and modified a few of the approaches I previously described. So it seems appropriate to revisit that old material and update it with some of the newer tricks I use while post-processing the audio files I've captured.

+++

Over the last few years I've had the opportunity to review a lot of "wild life" audio which normally involves digital recorders used to capture sounds over great distances. Often these recordings produce faint, noisy results that to the untrained ear possess nothing of interest. But after some looking around and a little practice, I've learned some techniques that work for amplifying weak sounds while filtering out noise to improve audibility. This has allowed me to go back and review hours of recordings that I thought were basically empty, only to discover an amazing amount of very interesting audio. This has proven so useful that I thought it worth while to pass along this information to anyone else who may want to give it a try. So here's my approach to post-processing my recordings using Audacity.

First, here's what you'll need: the free audio editing program Audacity (download from: http://audacity.sourceforge.net/ , get the 1.3.x beta, it's stable and has the features needed for this work); a reasonably good computer (probably the one you're using now will be fine, I used a five year old laptop for most of my efforts); and a good pair of headphones (over the ear type are best, you don't want stray noise getting in the way).

The rest of this post assumes you have isolated short segments of interesting audio worth post-processing. The processes described below may not work very well on exceedingly long audio clips. If you are starting out with a large audio file and need to review it for sounds of interest, I recommend you begin with this post about using Audacity to review large audio files.

+++

After installing Audacity, here's the process I use to first amplify, then high and low pass filter, and then noise filter a recording for best results.

-Open the audio file you wish to edit in Audacity and it will be displayed as a waveform in its own window.
-Go to the "Effect" menu, open it, then select "Amplify". The entire audio waveform will be highlighted and a window will pop up

-In the Amplify window it will provide a default Amplification(dB) and a New Peak Amplitude(dB). Normally it will automatically choose the amplification needed to achieve a new dB level of 0.0. This is often good enough for our purposes, and you can just click "OK" and be done.
-On occasion you may wish to use a higher amplification setting, which will cause "clipping" of the loudest sounds in your file. There are times when this is desirable (e.g. to over ride loud clicks in the foreground), and checking the block to "allow clipping" will force this over ride.
-Also note the "Preview" button. This allows you to test the results of the settings you've entered before committing changes to the file.Click it to see if you like what you hear.
-Finally, click OK and the whole audio file will be amplified.

The next thing I do is apply a couple of filters to minimize noise in higher and lower frequency ranges.

The first step is to apply a "Low Pass Filter".
-Go back to the Effect menu, open it, look toward the bottom and click on the Low Pass Filter.
-In the resulting "Low Pass Filter" window the settings I use most often are as follows:
-36 for the "Rolloff (dB per octave)" setting
-the default (0.7) for the "Filter quality" setting
-and 1750 for the "Cutoff Frequency (Hz)".

After making these settings, click OK and the frequencies above 1750 hertz will be continually reduced in volume by 36 decibels for every octave above 1750. The result is a recording with much of the high end hiss minimized (allowing everything below the 1750 frequency to "pass" unmodified".

Next use the High Pass Filter to minimize low end rumble and wind noise.
-Return to the Effect menu, open it, look toward the bottom and click on the High Pass Filter.
-In the resulting "High Pass Filter" window the settings I use are:
-36 for the "Rolloff (dB per octave)" setting
-the default (0.7) for the "Filter quality" setting
-and 315 for the "Cutoff Frequency (Hz)".

With these settings in plave, click OK and the frequencies below 315 hertz will be diminished by 36 dB, for each octave blow 315 Hz.

(Before discussing Audacity's Noise Removal tool, let me suggest that if you have access to Adobe Audition, even an older version like 3.0, it's Noise Removal tool offers far better results than anything I've been able to achieve with Audacity.)

Next, we want to use Audacity's "Noise Removal" tool.

-First, click the little icon at the top of Audacity that shows a magnifying glass with a plus symbol in it. This will zoom you in one step for each time you click it.
-Zoom in until you can see the individual seconds of your recording, left to right across the top of the spectrum window.

Look for a section in your recording that has the "noise" you want to remove, but contains none of the faint background sounds that you want to keep. It takes practice, but you'll be able to spot these areas eventually; they're normally the flattest part of the recording's spectrum.

Once you've found that quiet, white noise spot in your recording, use your mouse to click and drag across a couple of seconds of the white noise. This highlights a short segment of your file and defines an example of the noise signature to be removed by the Noise Removal tool.

-Now, go to the Effect menu again and from there select the "Noise Removal" tool. A little window will pop up and at the top, in "Step 1" you'll see a button labeled "Get Noise Profile".
-Click it, and the noise sample will be captured.

-Next, on your keyboard, hold down the "ctrl" key and hit the "A" key (Ctrl-A for short). This will select the entire audio file again.
-Now go back to the Effect menu and select the Noise Removal tool a second time.

In the Noise Removal tool section labeled "step 2" there are five settings you can adjust. For starters, try using these settings:
-Noise reduction(dB): 12
-Sensitivity(dB): 0.0
-Frequency smoothing (Hz): 150
-Attack/decay time (secs): 0.15
-Noise - Remove (radio button selection)

The Noise Reduction number is where you get the most bang for the buck. If it's a fairly quiet file you're working with, then a setting of 6 might be fine. If it's a very noisy file, you might try 12, 18, or even more. But be sure to use the "Preview" button in the lower left corner to see what your result will sound like. If you have the Noise Reduction number set too high, your result will have a "tinny" or metallic sound that is worse than the original noise. You want to select a number low enough to minimize that metallic sound, and high enough to minimize the noise in your recording.

-Click OK and the noise will be filtered from your file.

By this point, the Noise Filter, Low and High Pass Filters have probably knocked the overall volume level of your recording down a bit. So, as a last step, it might be advisable to re-perform the "Amplify" step described above. This should bring the recording level back up to 0.0 dB and make it suitable for basic listening on computer speakers.

Note that we haven't saved our work at any point in this process. Now might be a good time to to do so. But instead of saving it, you'll want to export it.
-Do this by selecting the "File" menu and then clicking on "Export".
-A box will pop up where you can enter a new file name (a good idea so that you don't over write the original file).
-Type in a new name and then hit OK.

As with anything, a little experimentation might improve your results. So feel free to play with the settings discussed above. But for a quick start to getting the most out of your audio files, these suggestions should work for most people.

Now you're done. You have an amplified sound file, with noise effectively reduced, and extraneous low and high end frequencies tamped down to improve audibility. It's time to give the file a play back through your head phones. Turn the volume up to a comfortable setting and you should be amazed at how much better the original audio sounds, and how many faint or previously inaudible sounds you can now hear clearly.

Using Audacity Spectrograms to Review Audio - A Cheat Sheet

This is a quick tutorial and list of actions that will get the first time user up and running with Audacity, for the purpose of reviewing their audio files visually, with spectrograms. This assumes you are already familiar with how to open an audio file in Audacity.

-Start Audacity and maximize the application's window to fill your whole screen
-The first time you use this tutorial you'll want to type "Ctrl-P" to open the Audacity Preferences window
-In the Audacity Preferences window select "Spectrograms" to bring up the associated options
-In the spectrogram options set window size to "4096 - most narrowband" (later versions of Audacity allow for much higher settings, but greater than 8192 may be of little use for this purpose)
-Set Maximum Frequency to 1200, and click the box to "Show the spectrogram using grayscale colors" (Gray scale is easier to work with until you're more familiar with spectrograms)
-Select OK to save your settings

See the image below for added examples of these settings...

-Now select File>Open and choose an audio file to load into Audacity
-Grab the bottom edge of the sound track when it opens and drag it down to fill in the empty space in the main application window (or you can hold down the Ctrl and Shift keys simultaneously and hit the "F" key to achieve the same effect)

-At the top left of the sound track, the file's name will appear with a small down arrow to the right of the name
-Select that arrow and a drop down menu provides options to apply to the track, select "Spectrum" or "Spectrogram" in newer versions of Audacity

-In the resulting spectrogram view, use your mouse to select a segment of audio to examine.
-Start with 10-20 seconds until you've become comfortable with the types of patterns to look for.
-Select the button in the top right of the main toolbar to "Fit Selection", this will cause the view to zoom in to the audio you've selected with your mouse

-Use the scroll bar at the bottom of the audio file window to jump the audio right one segment of time (based on the duration you selected above).

-Scroll through the audio a bit at a time and watch for dark spots in the spectrogram which indicate an audible sound has been recorded
-When you spot something worth listening to, click your mouse just to the left of the dark spot and then hit the space bar on your keyboard to begin playback
-Listen to the sound, and after you've heard it, hit the space bar again to stop playback

Here's an example of how coyote howls appear in an audacity spectrogram set up as discussed above

-Use this method to scroll, view, and selectively play back audio until you've completed the entire file
-If you find something worth isolating, use your mouse to select that section of audio and then the menu options File>Export Selecttion to save that segment to a new file.
-One of the biggest advantages spectrogram review has over the normal "waveform" review method (where you watch for big spikes in the audio file's waveform view), is how spectrograms show you howls that are otherwise hidden in the waveform. As an example compare the spectrogram view of the coyote howls above, to the waveform view of the same coyote howls, below. In waveform they are complete invisible and would go unheard if you weren't lucky enough to play back that segment of audio.

 
-After you've become comfortable scrolling through spectrograms, recognizing interesting patterns (sounds), and playing them back, you should try widening the view on your screen
-A three minute segment (vice the 20 seconds described above), gives good visual detail when in full screen mode, and allows you to review hours of audio very quickly (as compared to listening to the entire file)
-This is what makes it possible to record 9 hours of audio every night, and then quickly review it in under thirty minutes at some future date (more recording means more chances of catching a sasquatch vocal)

Other special notes:
-Most good sasquatch vocals occur between 500 and 800 Hertz, but can appear above or below that (although rarely seen above 1200 Hertz)
-Howls will look like long flat or wavering horizontal lines (-----), whoops look like the forward slash on your keyboard (/), woodknocks look like tall vertical lines (|)
-Dogs most often appear in the 350-500 Hertz range, and owls are all over the place
-In my experience, most good audio occurs between 10 p.m. and 4 a.m.

Triple Moan Howl from Morton, Washington

Kirk Brandenburg has been on a tear lately. Earlier this year he captured a great piece of thermal footage potentially showing a New Mexico sasquatch monitoring his camp one night. But before that, in August of 2010, Kirk was camping with friends in Morton, Washington, when he heard vocals starting up in the distance. Kirk had the presence of mind to grab his audio recorder, turn it on, and listen quietly. For his efforts, Kirk captured one of the best series of moan howls to be recorded recently. It makes for a nice spectrogram, and after cleaning up, has a bonus whoop or two at the end.

After you've enjoyed this clip, be sure to check out Kirk's thermal footage at:
http://www.youtube.com/user/studysasquatch

Best of the Sasquatch Bioacoustic's Video-Spectrograms

This list captures the "best-of" the video spectrograms published here at Sasquatch Bioacoustic and serves as an easy reference list for the interested listener.

+++

The Ohio Howl - The first recording of a "Moan Howl" known to have been captured, in 1994, by Matt Moneymaker of the BFRO. This comes from Columbiana County Ohio, near Wellsville on the Ohio River. The original clip may be found at: http://www.bfro.net/avevid/SierraSounds/911.asp#howls

+++

The Mississippi Howl - On December 19th, 2004 in Forrest County Mississippi, John Callender recorded a sequence of long moan howls, very similar to the Ohio Moan Howl of 1994. However, careful post-processing of John's recording reveals more than meets the ear, including a whoop and what may be the first known recorded instance of a "falsetto shriek" and a "yahoo" vocal. Both of these vocal types have been captured repeatedly in the years since.

+++

The Florida Howl - The first moaning howl recording captured in Florida, by Dan McGee, during a 2006 BFRO expedition to Lake County

+++

The Kentucky Vocalizations - On April 10, 2010, Billy Arndell and members of the Scottsville Ghost Hunters were visiting an abandoned house in a large wooded tract. Billy placed an audio recorder inside the house, near a broken out window, and captured this series of vocalizations while he and his friends talked outside.

+++

Recorded by Kirk Brandenburg at 5:56 pm, August 20, 2010, near Morton, Washington. He and his group had just arrived and were in the process of setting up their camp when these vocals began. Kirk had the presence of mind to quickly start his audio recorder and captured this great vocal sequence. The moan howls in this clip are highly consistent with moan howls captured in Ohio, Mississippi, Florida and Georgia. This clip begins with an indistinct vocalization, possibly from a different sasquatch, and ends with two whoops.

+++

Piney Woods Up Vocals - Captured on August 31, 2011 at 10:50 p.m. in a research area in Pendleton County, West Virginia. These ascending vocals follow shortly after two faint whoops and resemble similar vocals captured in Brunswick County, VA. The second half of this clip includes spectral amplification to bring out the faint initial whoops, and other details of the ensuing vocals. Compare the two whoops in this clip to the series of whoops captured in Decatur County, GA in March 2011, in this clip: http://www.youtube.com/watch?NR=1&v=u0wuRSFena4

+++

Decatur Moan Howl - While vacationing in south Georgia I decided to visit a remote forested area to listen to night sounds and make wildlife recordings. After sun set there were a lot of owls calling and several alligators growling from the nearby river. At one point I heard three wood knocks come from the forest, and as I continued to listen I heard two distant whoops. I left my recorder out over night and at about 12:05 a.m. on the 12th of March, the recorder captured this distant moan howl. If was quickly followed up with a bonus ascending howl, and then ended with three wood knocks.

+++

The Kentucky Vocalizations

This clip, "The Kentucky Vocalizations", is one of the more important recordings to surface recently in the effort to study sasquatch vocal types and communication patterns. This is not due to any particular clarity in the clip, in fact it's a great example of what not to do while making a recording. But the vocalizations captured here cover a range of suspected sasquatch utterances that have only appeared singly or in pairs in other recordings. In a sense, it becomes something of a touchstone for a broader range of sasquatch calls. It does so by establishing relationships between heretofore unrelated vocals, and in this case, most apparently spoken by the same vocalizer.

And it is the relationships between vocals that allows us to extend the potential content of the sasquatch vocabulary. It begins with a single instance of one form of communication captured in association with another, which creates a potential connection between the two (for instance, the moaning howls and possible response howl in the "Ohio Howl"). And then, with time and additional data, we find evidence to support or refute that hypothetical association. This activity of mapping and substantiating vocal relationships is a key technique enabling this type of study.

The Kentucky Vocalizations were inadvertently captured by the late Billy Arndell and a group of paranormal investigators known as the Scottsville Ghost Hunters. During the evening of April 10, 2010, the group visited an abandoned house in a large wooded tract in Allen County, Kentucky. Billy placed his audio recorder inside the house, near a broken-out window, and stepped back outside to converse with his friends. While they talked, the recorder captured an impressive series of vocalizations. Unfortunately their conversation steps on much of the recording, but careful filtering and amplification has salvaged many interesting features, including:

Whoop modified with trailing utterances - At the two second mark of the spectrogram playback, and again at the 15 second mark, a subdued "whoop" vocal is heard. These two whoops are unique with regard to the vocal notes that follow immediately after them. These trailing notes are, to date, not seen in any other potential sasquatch recording. And as a possible first occurrence, this recording takes on added value. This type of call will be listened for in future recordings of possible sasquatch vocalizations.

Moaning howl - At 20 through 29 seconds of the audio playback, a loud vocalizer (louder than the initial two whoops) emits two long moaning howls. These are very similar in construct to the moaning howls heard in the Ohio Howl (1994), Mississippi Howl (2004) and the Florida Howl (2006).

Integrated wood knock - Not a vocalization, but wood knocks are a frequently described signal in suspected sasquatch communications. From 21 to 23 seconds, during the beginning of the first moaning howl, three heavy wood knocks are made. They are difficult to hear in the original audio recording, but show up faintly in the spectrogram as light vertical bars intersecting the howl. With amplification, they are easier to hear in the filtered audio playback. Wood knocks are often integrated into sasquatch vocalizations and can be seen in both the Mississippi and Florida Howl recordings.

Woot vocal - The name of this vocal is an onomatopoeia, or a name that sounds like the thing it describes. This vocal type is not commonly heard, but it has been captured in other audio recordings. In this clip, three possible woots are uttered in rapid succession, at the 31 second mark in the spectrogram playback. They could be mistaken for wood knocks, but  the lack of a broadband, woody note suggests these are indeed vocals.

Yell - This vocal type is often long in duration, similar to a moan howl, but it is executed at a higher frequency. The resulting change in tone and timber creates a vocal that sounds very much like a human male yelling in the distance. Heard on its own, it would be completely indistinguishable from a human calling out. But in many instances, the yell vocal is captured in association with other suspected sasquatch vocals. In this recording, an ascending yell vocal begins just before the 32 second mark and climbs steadily in pitch for 3 seconds. Then it breaks to a higher pitched tone, briefly, before breaking again and descending in pitch to the call's conclusion. There are two additional short segments of "yell" in this clip, at the 38 and 42 second marks. But these are integrated into a unique call, discussed below in "pitch changes".

Whistle - From 37 to 38 seconds in the clip, four short notes are emitted, sounding very much like whistles. They could in fact be vocals, but the airy note they contain suggests a whistle. Other examples of this vocal type exist, but more need to be captured before a conclusion might be reached. The first three whistle notes climb rapidly in pitch, and the fourth drops to a lower pitch, below the third. Of interest is the fact that the fourth whistle is emitted during a second, shorter yell vocal from the vocalizer. This suggests a second sasquatch could be uttering the whistles in response.

Falsetto Shriek - This vocal type was probably first captured in the 2004 Mississippi howl recording. It rounds out the sasquatch vocal range, with moan howls at the low end, yell vocals mid range, and the falsetto shriek at the high end, or in the falsetto register (if compared to a human vocal range). This clip contains two falsetto shrieks, the first at the 39 second mark, and the next at the 45 second mark. As the second shriek plays out it drops out and in again at 52 and 55 seconds.

Pitch Changes - The vocals in this recording include abrupt breaks in pitch, to both higher and lower notes. These pitch changes have been observed in other sasquatch vocals with enough regularity to become something of an identifier in themselves. A future blog post will deal more specifically with pitch changes and what's been observed to date. But for this clip the reader should note the minor pitch changes at 35 and 36 seconds, and the significant pitch changes at 39, 42 and 45 seconds. These latter mark the transition from a yell vocal into and out of a falsetto shriek, as described above.

To our great fortune, the Scottsville Ghost Hunters knew they had something interesting with this clip, so they contacted Charlie Raymond of the Kentucky Bigfoot Research Group (www.kentuckybigfoot.com). Charlie and I know each other from a chance meeting during the 2010 BFRO expedition to Tennessee where he learned of my interest in the study of sasquatch vocalizations. Thankfully Charlie contacted me with this clip for closer scrutiny, and I am grateful to Billy Arndell and the Scottsville Ghost Hunters for sharing this great audio evidence with the sasquatch research community.

Scrutinizing the Florida Howl

It's time to look at another venerable vocal capture possibly attributed to sasquatch. This one is known as the Florida Howl, and it was recorded in Lake County, Florida, by Dan McGee, as he attended a BFRO expedition in January, 2006. You can read the report and see photos from that expedition on the BFRO website.

 
After some noise filtering and amplification three things emerge to recommend this as a sasquatch howl.

First, the familiar arched shape of a "moaning" howl, seen in both the Ohio and Mississippi video spectrograms.

Second, it shows an attenuated fundamental with strongest resonance in the F1 harmonic.

And third (and more importantly), there appear to be three deep wood knocks integrated into the howl, one at the beginning, and two at the end.

Integrated wood knocks are a key feature to look for in sasquatch vocals, and this capture has them. So +1 for the Florida Howl being the real deal.