top of page

The Strategic Use of Multiple Audio Recorders in Soundscape Investigations: A Coalescence of Data

by Steve Moon

Two recent examples of the strategic use of multiple audio recorders in overnight soundscape investigations are outlined here. These case studies illustrate the advantages of the use of multiple recorders as opposed to the use of a single recorder, when attempting to define observed Sasquatch behavior. The discovery and analysis of Sasquatch behavior is shown to be greatly enhanced using this method.

Weather in the Upper Midwest has been extremely unpredictable in the last few years. 2019 is no exception. So far we’ve had a relatively cool spring with periods of rain accompanied by bouts of extensive flooding, interrupted by brief sunny, warm periods. My research has proceeded at an intense pace, with solo camping trips in northeast and southeast Iowa, and southwest and northwest Wisconsin. Walkabout and overnight recordings in these and other locations have indicated a particularly high level of Sasquatch activity at this time. I’ve been sending research reports with photos and audio recordings to my colleagues at a rapid pace. Data is flowing!

In the last few months I’ve been experimenting with the use of multiple audio recorders for overnight capture of Sasquatch audio signals. The case studies here are of times when I have solo camped while actively investigating a location.

The use of multiple recorders in any investigative context is usually a productive strategy. My recent use of multiple audio recorders has provided me with additional insight into the behavior of the Sasquatch residing in two of my study areas. The success of these investigations has led me to routinely deploy two recorders rather than one for overnight investigations. The strategy involved in the layout of multiple recorders is always challenging and interesting, adding additional intrigue to the research process, and necessary complexity to the overall research design.

A single recorder with a pair of stereo microphones provides a two dimensional representation of the soundscape, with spatial distribution of sounds represented in a right and a left channel. The use of additional recorders allows for an analysis of the same soundscape in three dimensions. Additional recorders, each with stereo channels, deployed strategically within a study area, allow for a more detailed investigation of the soundscape. Familiarity with the study area by the investigator greatly facilitates a strategic placement of the audio recorders. In the examples below, placement was devised in response to key factors: physical setting (environment), prior experience or expectations regarding Sasquatch behavior (attraction to human activity, etc.) and placement of my campsite, which is always considered by me to be the ultimate Sasquatch attractant.

For several years I have deployed multiple audio recorders during day and night investigations. Typically, I will drop (deploy) a recorder at the vehicle that I arrive at a location in. At other times I will stage a recorder at a location early in the day, knowing that I or a group of investigators will be returning to the location that night. However, it is the strategic use of two or more recorders in soundscape investigation that can take both observation and analysis to the next level.

Brighton, Iowa: April 24, 2019

In mid-April I met up with friend and fellow investigator Adam Newman for a daytime scouting trip on the Skunk River near Brighton, in southeast Iowa. The area that we scouted is about a mile from the town of Brighton, and is a busy place in summer with campers and boaters. I like investigating such areas, always finding them productive in terms of Sasquatch activity. So I suggested that we check it.

About seven minutes after our early afternoon arrival, I recorded audio signals of a vocalization and wood knocks that I feel indicate acknowledgement of our presence by multiple Sasquatch. The vocalization was an odd sounding bird call. It tried, but was not really owl like. It seemed too forceful. It was a complete one-off. I heard nothing else like it during our hike, which lasted for about an hour and a half. Because of the timing of the vocalization and wood knocks, and their location near the parking area, these signals followed a pattern that is considered by the Lowlanders to be typical of Sasquatch sentry or warning signals.

Five second spectrogram image and sound file below of the call that was recorded upon arrival.

Adam Newman examining an intricate stick structure that shows signs of recent manipulation.

An intricate stick structure gallery was encountered by Adam and I, and it was determined that construction was very recent on one of the more intricate structures observed. Flood waters had recently receded from the valley terrace that we were on, and some elements of this structure were not coated with mud, and so had to have been added after the waters had receded; so within about the last week. Coupled with the sentry call upon our arrival, indications were that this area was extremely promising, requiring further research.

The success of our scouting trip prompted me to return for an overnight investigation as soon as I possibly could. I was able to get away a couple of days later, at mid-week. Adam was unable to join me, so I solo camped, hiking from the parking area into the woods along the river for about 800 hundred feet.

In preparation for the trip, I had fitted four audio recorders with new lithium batteries, and optimized all of their settings. Each recorder was matched to an overnight box with stereo microphones, and tested. The resulting systems were then prioritized for deployment based on the study environment, but also on the quality and capabilities of each recorder. The recorder which I had the least faith in was deployed next to a parking area where there is a lot of noise from a nearby highway. This recorder did indeed fail, and has since been retired for good.

An abandoned road bed lies at the base of the escarpment, serving as a transition from floodplain to upland.

Eastern Iowa was finally awakening from dormancy after an unusually long and cold winter. Wildflowers were out, and local residents were just beginning to hunt for morel mushrooms. Rivers had all finished flooding for the time being, and had retreated back into their banks. Foliage was poking up through the alluvium left behind on flood plains, but budding undergrowth hadn't yet begun to obscure the view through the woods. On the day I camped out it had rained lightly in the morning. In the afternoon the sun was out, and winds were calming as they switched from south to north. After what had been a long cool period it was now warm with a predicted overnight low of 45 degrees, with winds further diminishing late. Insects were still dormant. Conditions were absolutely perfect!

Upon arrival in early evening, I deployed four audio recorders. Three were placed along a fence line near state property signs, from one end of the property to the other. The fourth recorder, with a pair of binaural in-ear microphones, served as my walkabout recorder, and was placed in a waterproof box for deployment as an overnight campsite recorder as I was setting up camp.

The idea to use four recorders instead of the usual single recorder occurred to me because of the linear shape of this particular piece of property. It is in a narrow band that follows the edge of the Skunk River for a little over 2,000 feet. No way could I predict where along that strip of land there would be activity, other than the fact that I knew that the Sasquatch would be attracted to my campsite. My preference is to sample as much of an area as possible when I am new to it. So, instead of deploying the usual single recorder at my campsite, I deployed multiple recorders in an effort to optimize my results.

I set up my camp in a spot that provided good visibility on both sides of the Skunk River, and by about 7:30 PM had settled into my favorite camp chair. I chose not to mess with a campfire because my experience is that a fire interferes too much with visual observations, as well as audio recording, and therefore my preference is to cold camp. So I sat quietly as darkness fell. At 8:15 PM I heard two loud splashes in water, as though two chunks of wood or tree branches had been thrown in the river. Twelve seconds after the splashes I heard a short but interesting two-tone vocalization.

Thirty-second spectrogram image showing the splashes in the left channel and the two-part vocalization in the right channel.

Five-second spectrogram image showing the two-part vocalization.

I immediately assumed that the sounds I was hearing were the result of typically aggressive Sasquatch behavior. I had walked into the woods, made a bunch of noise setting up my camp and deploying my audio recording gear, and then sat quietly in the darkness. Apparently, after a while the Sasquatch couldn’t stand my passive behavior any longer and resorted to a display of aggression, the purpose of which was to encourage me to leave.

The bank of the Skunk River in the area of the splashes. The distance from terrace level to water level is about ten feet.

I sat there to see what would happen next. Within a half hour or so it became very dark. My eyes were fully adjusted to the darkness, but still, I struggled to make out details in the surrounding landscape, which was greatly compressed by the two-dimensionality of the darkness.

To my delight, I soon observed two spectacular animated displays of very bright white eyeglow. The first was due east of my position, directly in front of me, toward the parking area, at a perceived distance of approximately 150 to 200 feet. This eyeglow was in the form of a single vertical arc moving toward the ground. The second eyeglow display, minutes after the first, was a horizontal movement between my camp and the river. It seemed as though a Sasquatch had run past me from the general area where the water splashes had occurred, in so doing, moving away from where the first eyeglow had appeared. This second display was in the form of two loping arcs, which I interpreted as being two long bounding leaps, moving several (6 - 10?) feet with each arc, at a perceived viewing distance of around 100 feet.

My interpretation of these amazing eyeglow displays is that a Sasquatch lowered itself from a standing position to ground level while observing me, made its way closer to my position, and then ran past me. It all seemed very Squatch-like, to me! Of course all of these movements were completely silent from my perspective, as is typical of a Sasquatch. The next morning I looked for prints in the fresh alluvial deposits, in areas where the eyeglow had been observed, and found none. This is also maddeningly typical of a Sasquatch.

A recorder (recorder two) was placed about two hundred feet southwest of the campsite recorder (recorder one), just inside the woods. The campsite was in a large clearing. The campsite recorder captured the sound of two branches or chunks of wood apparently being thrown in the river, and vocalizations. Recorder two was along the abandoned road lying at the base of the escarpment demarcating the transition from the upland to the flood plain that I was camped on. Recorder two captured two sets of two wood knocks, five minutes before the sound of splashes in the river. The two instances of splashing in the river were recorded with recorder two, providing critical time-synchronicity between the two recorders.

Fifteen-second spectrogram image of two sets of wood knocks recorded by recorder two, five minutes before splashes were recorded in both recorder one and recorder two. A vocalization is also present, captured only in recorder two. A separate vocalization was recorded by recorder one and not by recorder two.

The wood knocks recorded with recorder two are interpreted as apparent signaling between two Sasquatch. No directionality is detected in the wood knocks, which both seem to be in the center of the soundscape. I speculate that the two Sasquatch using wood knocks to communicate with one another were also coordinating activity with one another. I further speculate that at least one of these two Sasquatch was the individual responsible for the splashes in the river, in the left channel of the campsite recorder. It is entirely possible that the perpetrator of the other wood knocks captured by recorder two was responsible for the two part vocalization in the right channel of the campsite recorder, which quickly followed. Had it not been for the use of multiple recorders, the wood knocks, which were not audible in the campsite recorder, would not have been heard or recorded, and the above interpretation of Sasquatch behavior would not have been attempted or possible.

Sugar Camp, Wisconsin: May 3, 2019

Two weeks after the above field investigation I visited my friend Rick at his cabin on an island in the middle of a large Black Tamarack bog in northwest Wisconsin.

Upon arrival in late afternoon, I set out three audio recorders. One recorder (recorder one) was set up at my campsite, which was on a small island in the bog, separate from a larger island where the cabin is located. A second recorder (recorder two) was deployed on the opposite end of the island that I was camped on, approximately 80 yards north of recorder one, further away from the cabin. A third recorder (recorder three) was placed on the big island that the cabin is located on, at a location about 120 yards southeast of the campsite recorder, at a maple sugar shack.

I started the campsite recorder at 9:00 PM, upon turning in for the night. The other two recorders had been recording for an hour. All three recorders ran successfully for the entire night.

Two hours after turning in, at 11:05 PM, I recorded a remarkable combination of wood knocks and heavy thumps. The thumps and knocks were quite loud in the campsite recorder. The same knock and thump event was recorded in recorder three, at the sugar shack, but was not nearly as loud from this location. Further, the signal in recorder three was in a channel that pointed towards my campsite. Given the combination of the directionality of the signal in recorder three, and the close proximity of the signals to my campsite recorder, it was easy to eliminate the cabin as the source of the thumps and knocks, and to determine that the sounds had more than likely emanated from very near to my tent.

Five second spectrogram image of the combination of woods knocks and thumps.


Clearly, the use of multiple audio recorders adds a dimension to Sasquatch soundscape investigations that a single recorder fails to deliver. Being able to listen in three dimensions rather than two allows for the convergence of separate data sources, providing a greater amount of data for a finer analysis of events. The process of strategizing for the use of multiple recorders engages the investigator in aspects of the study area environment, the expected behavior that might be encountered, and the makeup of the investigative group, to name only a few of the many attributes that come into play. Research strategy becomes dramatically altered when one ventures from two dimensions into the third dimension.

So, this is one of the lessons that I learned while conducting Sasquatch research this spring. The analysis of convergent sound signals captured by multiple time-synchronous audio recorders allows for a significantly more refined and informative investigation into a given study area soundscape, and the Sasquatch activity that is observed therein.

Steve Moon

bottom of page