Reports in progress...
Assembled reports, comparisons, & paired recordings...
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A Wildlife Acoustics EM3 and a Pettersson D1000x recording side-by-side in Kanab, Utah in 2011 by John Chenger.
This was not intended to be a controlled direct comparison; however at least two distinct sequences were recorded simultaneously by both devices and provides a rare opportunity to see how different microphones respond to recording the same ultrasound in a field setting.
Additional samples are available from each device from this night representing post-processed files ready to be viewed in SonoBat. Disregard timestamps as neither unit was set for the correct time zone.
EM3 and D1000x Samples
A Pettersson D240x +MP3 recorder on August 28, 2005 placed at Cold Air Cave in Pennsylvania by John Chenger.
This detector was monitoring the bat activity on a talus slope in a river gorge a few hundred feet from a small cave entrance. This is a small numbers of examples of typical recordings made in field conditions with the D240x rigged to automatically trigger for passive monitoring.
D240x Myotis spp. and Perimyotis subflavus simultaneous recording
D240x PERSUB Additional Samples
240x EPTFUS Additional Samples
D240x Passive Recordings
Bat Detector Sample Recordings
These WAV files can be opened in Quicktime but are really intended to be viewed in detail with SonoBat or another similar spectrogram analysis software.
May 1, 2012 Directional Microphone Trial
Initial results of WA's upgraded directional microphone solution pitted against the standard Pettersson D500x external microphone.
Wildlife Acoustics SM2 384 SMXUS
Wildlife Acoustics SM2 384 SMXUT
July 18, 2012 Passive Monitoring Trial
These are paired recordings between a Pettersson D500x w/ext mic, a Wildlife Acoustics SM2 384 with a standard SMX-US microphone with windscreen, and another SM2 384 fitted with a SMX-UT microphone with the directional horn accessory. Recorded at Big Ice Cave at Lava Beds NM in California.
Wildlife Acoustics SM2 384 SMXUS
August 11, 2012 Passive Monitoring Trial
For most of the spring and summer of 2012 Chenger has had a long term passive monitoring station located in Carlisle, PA overlooking an intermittent wetland. Two detectors have been running almost continuously and this August 11, 2012 data set is simply one typical night of many samples.
Wildlife Acoustics SM2 192 SMXUS
Wildlife Acoustics SM2 192 SMXUT
August 10, 2012Passive Monitoring Trial
Bat Detector Second Impressions and
Microphone Sound Quality Comparisons
Below we intend to demonstrate real-world, side-by-side comparisons of popular bat detectors using -real- bats approaching from random directions; just like a real field survey would present. This has the drawback of being very time consuming, and very expensive, and requires essentially expert users to not only maintain the equipment but to find proper device settings and microphone placement. In addition, significant resources are expended expert vetting files to make sure we are really comparing bat calls, and not some other non-bat noise. But the advantage is that it does not introduce bias from "lab" or "controlled" studies with artificially generated noise that will inevitably favor certain microphones. If any manufacturer disputes results we kindly ask they submit their own paired recordings including detailed methods and we will be happy to include them on this site.
We try to stay away from hasty first impressions particularly of newly released or unfamiliar equipment. Inevitably some first impressions will be incomplete or even flat out wrong, with only time, experience, and direct comparisons with familier devices being the guide to work thru the quirks of a system and tease out it's best performance under good conditions. Our Second Impressions represent some thoughts and data after we've become more familier with the device and have started to compare it with others. Second Impressions should still be thought of as an educate, but very preliminary review. Consider that high end devices may require significant time investment to find ideal settings and workflows to make fair direct comparisons. With the overzealous marketing hype, rather questionable reviews found online, and significant time and money investment high-end bat detectors represent, our colleagues constantly ask our advice on how newly released devices stack up with tried and proven equipment. Therefore, we offer these Second Impressions to satisfy that crowd; but just don't take our words- we also offer actual screenshots and .wav recordings for download for you to see what we see for yourself. That's no marketing hype.
Preliminary representative results from testing a variety of bat detectors and microphones in a standardized test over a range of frequencies. While not a sophisticated "lab" test, all devices were tested using the same transmitter in a specific housing under similar conditions.
Wildlife Acoustics SM2 384 SMXUS
This is a representative selection of screenshots showing individual paired pulses recorded simultaneously with a Pettersson D500x w/ext mic, and a Wildlife Acoustics SM2 384 with a standard SMX-US microphone with windscreen. This was a one night recording session at Lava Beds National Monument in California.
January 21-25, 2013 Passive Monitoring Trial
This trial introduces the Batlogger and Anabat to the D500x and SM2. We will be seeing a lot more from the Batlogger in the next season. The Batlogger and SM2 feature omnidirectional microphones, while the D500x and Anabat are more directional.
Wildlife Acoustics Echometer Touch
May 12, 2014 Second Impression
Initial results of WA's Echometer Touch recording alongside a Pettersson D500xSE showing simultaneous paired recordings.
Binary Technologies AR125/FG/MiniMic
May 10-14, 2014 Microphone Trial
Initial results of ten different microphone configurations/devices from three major manufacturers.
(Major project- in progress)