Wildlife microphone - Page 1
Forum section: electronics / projects

author: B J
author_rank: Contributor
timestamp: June 18, 2020, 08:15:54 pm
content: I have three trail cams I have built up myself. Enjoying all the pics. Now I want to build a system to record sounds. Any suggestions on a good inexpensive microphone that is sensitive and has good sound quality? Thanks

author: sam[PS]
author_rank: Contributor
timestamp: June 26, 2020, 05:14:22 pm
content: I'd look for a good quality piezo capsule. "Measure" grade ones are basically flat in response so they are very precise but don't realy "sound good" because to human ears flat response tend to sound boaring nowadays. However it's easy to post process them. Philips used to make good ones if you can find them. Tcheck on EEVBLOG youtube chanel there is a video series on designing mic frontend and i belive one of the video cover that type of mic.For outdoor use don't forget wind blocking fluff.Just my 2cts ...

author: B J
author_rank: Contributor
timestamp: June 26, 2020, 08:16:18 pm
content: Thanks Sam -- At this time I am building a system using the WM61A. From what I have read, it looks like it is a good place to start. I will keep your suggestion in mind as I progress, and may come back and take a second look at it. Also your wind fluff is something I have thought about, but at this point need to do more head scratching.

author: Buriedcode
author_rank: Super Contributor
timestamp: June 26, 2020, 08:21:41 pm
content: That Panasonic capsule is remarkably good for the price. There is a "mod" to improve its SPL handling, but unless you're recording massive music venues or close micing drums, its not needed.I'm wondering if you'll need any compression or limited in case something "loud" is near your mic. Probably best to get something working and adjust the gain to give a good balance between distance sounds, amplifier noise, and close sounds, and then add on if needed.What are you recording with? Or are you biulding that part too?

author: B J
author_rank: Contributor
timestamp: June 26, 2020, 08:46:31 pm
content: Too hot to do much outdoors, so I am hanging around the computer and picked up on your return already. Thanks. Your thinking is right along where I have been at, as far as the SPL thoughts.To start with, will be using an old battery cassette machine. With a little circuitry, I can have it turn on and off with sounds that are picked up As far as a little AGC, if needed, I will probably just use an averaging peak detector, and drive a LED into a photoresistor. Something very simple that I can play with, yet get good results. Will be putting in another Op Amp and can put the LDR in the feedback circuit very simply.

author: wizard69
author_rank: Super Contributor
timestamp: June 27, 2020, 07:32:21 am
content: Quote from: B J on June 26, 2020, 08:16:18 pmThis is very interesting because just the other night a fell into a rabbit hole looking at all the various Mic preamp circuits out there. I really have(had) no intention of making a microphone itself but now I fear another night spent looking at various types of microphone capsules and pickups.Some time ago I had looked at MEMS based microphones for a project that never really got off the ground. There are advantages to using something like this:https://www.infineon.com/cms/en/product/sensor/mems-microphones/im69d130/, if you go digital in your recording system. These sorts of microphones avail themselves of setup in arrays winch can be used for directional determination and audio processing techniques. That is you could use microphones to find a sound of interest and turn the camera that way and maybe even filter out some noise.By the way the mention about wind noise is important as that can be very significant in the wild. It is a problem for anybody recording outdoors. There is no one right solution here.

author: cdev
author_rank: Super Contributor
timestamp: June 28, 2020, 04:51:18 pm
content: You can make a very directional "shotgun mike" using PVC tubing. Another way to get very focused directionality is to use a perfectly spherical pot lid (from a kitchen supply store) as a reflector.