Monongahela

A site dedicated to the review and analysis of potential sasquatch vocalizations, Sasquatch Bioacoustic combines techniques from the domains of intelligence collection, audio analysis and bioacoustic studies to examine the evidence of sasquatch through their vocalizations. ~Monongahela

Wednesday, April 7, 2010

The Second Recorder

I wanted to make this second post, a "part 2" if you will, on the results of my first outing of the year on March, 20th. This distinction is useful because on that outing I had a second audio recorder rolling, and its results were better than my in-camp recorder on a phenomenal scale. While my in-camp audio recorder did capture some great vocals and wood knocks as discussed in this other thread: First Trip of the Year - March, 2010, the results from my remote recorder were so extensive that I didn't want to risk confusing the two, and have people thinking that I could actually hear all these other vocals from my campsite location, I couldn't (if I had I probably would have bugged out).

I've posted two dozen audio highlights from a recorder and parabolic microphone which was positioned to the northwest, on the back side of the ridge north of my camp, and in the direction of the original vocals I captured with the in-camp recorder. The access road to my campsite passed not far from where the parabolic was placed in the forest. And the parabolic was aimed northeast, to cover the flanks of the ridge between it and my camp, the floor of the valley below, and the flanks of a large ridge a half mile to the north.

The recordings from the remotely place parabolic are on the same page as the snippets from my in-camp recorder, and can be distinguished by their file names which begin with WS500* (the model of recorder in use). All the in-camp audio files from my earlier post begin with WS310* (*additional numbers deleted). And the link to the audio collection is:


http://sites.google.com/site/mongahela/myrecordings2010-1


While each of the audio samples includes a brief descriptive text along with it, I'll offer here a few words on why I chose the audio samples that I did.

The first five audio snippets I thought notable because they demonstrate that wood knocks and vocals can occur during the day time. These were captured between 2:00PM and 8:00PM on March 20th. They also show potential for substantiating the hypothesis that wood knocks and vocals may serve to announce the arrival of a human on the scene. Notes next to each audio sample extend this speculation.

Beginning at 9:09 p.m. that evening, the parabolic began to pick up howls, bark, hoots, and much later, whoops, that grew in volume and intensity, before fading away to intermittent periods of quiet. This activity was most intense up until about 1 a.m. that night, but occasional outbursts of the same vocals were captured until as late as almost 5:00 a.m. on the 21st.

Early in the recordings, the vocals are very owl-like, or very dog-like. But the owl is noticeably loud, louder than other owl vocals captured that night. But as time goes by in the recordings, and as demonstrated in the audio samples, the hoots and barks tend to lose their form. By 9:30 the barks occasionally ascend in a slight whoop-like fashion. Not a clear whoop, but losing that canine sound. Also by 9:30, the first wood knocks begin to appear intermixed with the vocals.

There are a series of three or four key audio samples that are most noteworthy in this collection. One demonstrates an association between the bark vocals and wood knocks. Another demonstrates wood knocks associated with the loud owl hoots. Yet another key sample offers the first association of the hoot vocals and the bark vocals with each other (with wood knocks included). An important feature of this sample is the differing tone between the hoots and barks, indicating two different speakers are involved, and each making a unique type of vocal. This is demonstrated again in audio samples from later in the evening, and indicates that the two vocalizers were moving together over the course of the evening.

Based upon the substantiation established in those key samples described above, I carved out a few more interesting samples. Some are better versions of whoop-like barks. Some include faint whoops that you have to listen closely to hear. Some demonstrate a ululating form and other combine howls, whoops, barks and wood knocks all in one segment. And the owl hoots become noticeably absent in some of the later samples. They seem to have been replaced with howl-like vocals.

And at the end of the collection I added a very unique vocal, unlike any I've ever heard before. It's a higher pitched voice, possibly not one of the two speakers described above, and it lets out a short wailing call that sounds to me like "wahoo". It could be an owl call, but I've never heard an owl make a call like that. However it is unusual and I share it for your enjoyment.

Please feel free to share your opinions, good, bad or indifferent. I know some folks won't hear what I or others hear, and that's ok. I want to get all the opinions and angles I can and make this a useful conversation.

Recording Pointers For Beginners

After spending many days last year with my audio recorder turned on, I've realized a few things that have, over time, improved the quality of the recordings I make. With the advent of another season of research before us, I thought it would be useful to share some suggestions, with the hope that new audio recordists (such as I) can use them to get a head start.

The best place to start is with equipment, but not in terms of defining a long list of recorders you should consider. There are other sites and discussion forums dedicated to equipment and their capabilities, so let's not retread that ground. Instead, I'll point to an affordable, entry level rig, that will let almost anyone get into this hobby without dropping too much coin.

My choice of equipment was driven by two things. One, the fact that I'm fiscally conservative, and two, that I've listened to a LOT of bad recordings in my life and along the way learned a little about what made them bad to begin with. So when I set about searching for my new rig I knew that (a) the microphone had to be as good as my wallet will allow, and (b) the recorder should be good, but its not as important as a good mic (post processing can do a little to salvage the impact of a poor recorder, but nothing can improve the hearing of a poor quality mic).

I really didn't want to spend circa $300 on a nice digital recorder such as the Zoom H2 or Edirol R-09. Instead, I wanted to piece together something for under $100, just to see if I could get good recordings out of it. Starting with the mic, I found this hand made gem on Ebay (http://www.giant-squid-audio-lab.com/gs/gs-podcast_stereo.html ) and purchased it on sale for about $55. Then for the recorder, I searched Ebay again and found that Olympus has a store front where they push all manner of older stock and refurbished new stock. I liked the technical specs of their WS-311m recorder (despite the poor onboard mic performance) and scored one at a remarkable Ebay price of just $35. With shipping, my $90 in equipment came to a little over $100, so I was close enough.

From this point on I'll just try to offer bullet suggestions with short explanations behind them:

1 - Turn On Your Recorder Before You Arrive At Your Research Area - I have missed wood knocks that happened just after I parked and stepped from my vehicle. I wasn't ready, but they were ready for me. That warning wood knock (or vocal) that announces your presence in the area has been reported by more than a few researchers.

2 - Carry A Recorder That Has Lots Of Capacity - I recommend a minimum of 12 hours recording time, both in storage capacity and battery life. The Olympus I describe above can achieve this while recording at "almost" its highest quality level (another important goal). This allows you to turn the recorder on and just let it go. There's really no reason to turn a recorder off unless you know you will be away from a computer for days and unable to offload your recordings (which should also help you justify buying a little netbook computer to take along on your expeditions).

3 - Be Quiet! Give Your Recorder A Chance To Do Its Job - Remember, you're trying to record something living out there in the woods, and you'll quickly learn that your buddies' joshing around is stepping all over those distant wood knocks and vocals that you'll hear in your headphones when you get home. Whenever possible, position the recorder away from the crowd. When in camp, set the recorder outside of camp 50 or 100 feet so that it has a chance to hear more of the woods, and less of the camp (but bring it into camp when everyone goes to bed, you may get a visitor that you'd like to catch on tape). Also, when you're out with the crew on a road hike, try to keep some distance from the most talkative part of the group. And while conversation is encouraged as an "attractive" behavior in these outings, occasionally asking folks to pipe down so you can record that whoop-knock duet is probably ok.

4 - Recording On The Go - It's unavoidable, but you'll pick up lots of noisy interference if you walk around with your recorder. A couple things I've done is to clip the external mics I use (they come with little alligator clips) to my shirt collar, away from my face. That keeps them clear of my body and minimizes some of the handling noise. I've not figured out how to carry a recorder using integrated microphones on my person and do so quietly. Someone suggested a vest with ample pockets and attachment options. That might help, at least to keep it out of your hand. But the sounds of your boots hitting the ground will be an ever present distraction, so try to tread lightly and pause frequently.

5 - Keep Your Directions Straight - If you have a stereo mic, as the one I mention above is, pay attention to which mic is pointing where. When I'm travelling with my rig I keep the right channel mic on the right, and left on the left. That way, if I capture a vocal but am not sure where it came from, I can look at the stereo playback later and possibly determine left or right from the signal strength. I also do something similar when I "post" my recorder outside camp. I point the left channel north and the right channel south. Because they are omni-directional mics they pic up audio well in nearly every direction, except for directly to their rear. Pointing them in opposite directions again helps me know which way the vocal came in from. (If you can, use a compass to accurately determine where north is. This bit of added precision may prove very useful some day, as the post-processing software will be able to make use of that information).

6 - Play With Your Equipment - Get to know your equipment at home before you take it out in the field. Experimenting and learning the fundamentals in your living room is a lot less aggravating than trying to do it in the field. And when you do get out there, you'll be ready to go and not waste any time learning to use your rig.

7 - Establish A Listening Post - When you're out in the field you should be recording all the time. But doing anything with a recorder in your hand is tedious at best. If you put the recorder 50 or so feet out of camp as suggested above, what you've effectively done is established a listening post. But there's no reason why your listening post has to be that close to camp. Consider leaving a recorder out in the field, overnight, and just driving away. Its amazing what you can capture when you're presence is not a part of the scene.

8 - Multiple Recorders - With early success, you may find yourself looking at newer and better recorders and mics. It's ok, don't be ashamed, we all do it. And there are good reasons to do it. For instance, I'm writing this paragraph from the camp chair of my first outing of 2010. I have my original Olympus WS-311m about 50 feet away recording from a tree where I hung it. My second recorder, an Olympus WS-500 is a half mile away, just past the top of the ridge I drove in along. It is outfitted with a parabolic microphone. Thirty minutes ago I heard two loud owl hoots in response to my whistles and wood knocks. The hoots came from the direction of the parabolic mic, so hopefully I'll have two recordings of the same sound in the morning. (Since then I've heard some voice-like vocals moving along the top of the ridge to my north, and a few strange whistles, too. Something might be coming in.)

9 - Turn The Tape Over - Or more precisely, don't let your recordings grow too long. With digital recorders the file size can get very large and make it a challenge to work with on your computer. When I have my recorder with me I try to stop and then start a new recording every 30 minutes or so. This size doesn't tax my computer too badly and minimizes the amount of file parsing I have to do in post processing. Naturally long recordings are unavoidable when you leave the recording rolling while you go to sleep.

10 - Time Hacks - It's always a good idea to mutter a few bits of information into each new recording that you start. For instance, the date and time are very important. You should also mention your location and anything unique about the environment or set up. I often indicate where I am and which direction the left and right mics are pointed in. This may seem an annoyance at first, but a year or more down the line, when you go back to listen through some of the hundreds of clips you'll have collected, you'll be happy that you did take the time to make these comments.

11 - Parabolic Dish Microphones - After you've got a little recording time under your belt, you might be tempted to invest in one of these. They have a lot to recommend them, but they have some downsides, too. First, they can capture and focus the sounds coming from the direction in which you point it, making faint sounds much louder. And if you're recording from a "listening post" over a large area, they can really pull in distant sounds nicely. But the most common parabolic dish rigs are monaural, and not stereo. So you lose the sense of depth perception that stereo recordings can offer (although stereo parabolics do exist and aren't too hard to build). And because of their size they are a challenge to use when on the move, where they create lots of "mic" noise, and pick up more of your hiking sounds and less of the sounds around you.

12 - Wind Screens, To Muffle Or Not - Last year I went a-recording and halfway though my hike lost the wind screen from one side of my stereo recorder. When I listened to the recordings later I was amazed at how great the difference was between a screened versus a non-screened mic. The unscreened mic had more wind noise for sure (but I can mitigate that in post processing), yet its recording was loud and crisp. The channel with the wind screen on it however had disappointing recording performance. It was less windy by far, but it was also muffled. And when I compared recording levels of sounds that had been evenly picked up by both channels, the wind screen often lowered the recording level by 5 to 9 decibels! That's an unacceptable hit to recording levels in my opinion, so I no longer use wind screens, even in the windiest conditions (recording in heavy wind is just a waste of time anyway).

13 - Wait For the Right Moment -
When out in the field, don't bother making knocks or calls while a jet is flying over or an engine is running in the vicinity. If you can hear it with your ears, your recorder can hear it better. And in my experience knocks or calls will very often get faint responses. But your recorder will never hear them because of that jet flying over. Best time to make a knock or call is when it's dead still. And make sure everyone stays quiet for at least 5 minutes after you knock or call. And building on this, the best time to go recording in the field is when the weather is best, a nice high pressure cell with no winds. You'll find the nights can be as clear as a bell and sounds will carry a very long way. So watch the weather channel for high pressure in your area, and never miss a chance to go recording.

These are just some of the things I've come up with in the field, and they've made my life easier. Hopefully they'll help you, too.