tag:blogger.com,1999:blog-8042569099194536366.post2783888095489170945..comments2024-03-28T12:48:59.344+00:00Comments on Captain Bodgit: Bat Call Logger: full-spectrum analysisSteveDeehttp://www.blogger.com/profile/10645378028590228663noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-8042569099194536366.post-1921400389223046382018-06-08T11:58:48.772+01:002018-06-08T11:58:48.772+01:00The problem with trying to choose a microphone for...The problem with trying to choose a microphone for bat detection, is that the specifications rarely include the frequency response above 20kHz. The exceptions include the Patterssen USB mics which cost SEK3500 (about £300).<br /><br />Most USB mics aimed at the audio market won't be suitable because the internal A-D converters generally have a max sample rate of 44-48kHz. According to Harry Nyquist, the sample rate has to be at least twice the upper audio frequency that you hope to capture. So even the sub 500 will probably only have a high frequency response up to 24kHz (i.e. 48k/2). If you already own one of these you could establish the sample rate (are you on Linux, OS or Microsoft?).<br /><br />Even if you buy a cheap electret mic insert (£5 - £15) you still need a sound card with a sample rate of 192kHz to give a high frequency response of 80-90kHz. (some notes here: https://captainbodgit.blogspot.com/2018/02/bat-call-logger-wolfson-frequency.html and here: https://captainbodgit.blogspot.com/2017/09/building-your-own-bat-detector-is.html).<br /><br />As I've already been around this loop, I can tell you that none of my laptops can sample audio any faster than 48kHz.<br /><br />Maybe the best option would be an audio USB dongle + a Panasonic WM61A mic insert, but a quick search for dongles that support 192kHz sample rates didn't reveal much below £100 (check out M-Audio & maybe Toslink).<br /><br />Once you have the ability to record bat calls on your computer, how will you trigger record?SteveDeehttps://www.blogger.com/profile/10645378028590228663noreply@blogger.comtag:blogger.com,1999:blog-8042569099194536366.post-34567621343202382982018-06-08T00:01:45.448+01:002018-06-08T00:01:45.448+01:00So... what are the chances of 50 quid usb condense...So... what are the chances of 50 quid usb condenser mic (like the sub zero 500) of working nicely to record up to 80khz? I’m only single digit IQ, and poor as a church mouse, so looking for something like the dodotronic without the cost!Anonymoushttps://www.blogger.com/profile/04087093950026149326noreply@blogger.com