I found a tutorial from 8 years ago that showed a build for Lom electromagnetic microphone, Electroslusch. Apart from their small capsule microphones that seem quite similar to Micbooster with some high quality 3D printed casings. I appreciate how open source Lom are with their microphones. Showing a lot of data for their Geofone and now having building kits for those too. https://makezine.com/projects/weekend-project-sample-weird-sounds-electromagnetic-fields/
This seems like quite a useful project, it appears all I really need to make it is some quite cheap transistors so will look into added that to my arsenal of sound design tools.
Zach Poff’s Contact Microphones
Another open source researcher and teacher is Zach Poff who has quite a simple tutorial for making contact microphones from piezo discs. https://www.zachpoff.com/resources/building-contact-mics/
I missed out on microphone building in first year and figure it would be good to have the basis of microphone building done by the end of the year.
In this build, Poff heavily recommends using a pre-amp. I use my JrF Contact microphone with a XLR adaptor, as apparently the XLR input picks up more frequencies than a quarter inch jack – but I have never tried a contact microphone with a preamp. From what I could see from the Electrolusch build, certain resistors can boost low end. This might be a good way of achieving a more rounded signal pre-edit phase and might explain some more professional field recordist’s clean ‘unedited’ signals from contact microphone recordings which I often found hard to believe had not be at least EQ’d slightly.
Alex Rice Piezo Preamplifier
http://www.richardmudhar.com/blog/using-piezo-contact-mics-right/
http://www.richardmudhar.com/piezo-contact-microphone-hi-z-amplifier-using-a-fet/
I think it’s high time I start exploring these simple builds. If I am successful it could lead to more slightly ambitious territory with building kits, and also more satisfying trips field recording with things I had built myself. https://www.cigarboxguitar.com/knowledge-base/using-piezos-in-cigar-box-guitars-part-1-piezo-basics/
MicBooster Small Capsule Microphones
These experiments could lead to more ambitious microphone projects like the MicBooster clippy kits.
Whilst they sell their Clippy’s for around £120. They have Cardioid capsules amongst others which might be interesting to try. The electret primo omnidirectional capsule is the same used by Lom. Low-noise with lots of high frequency detail. I am interested in testing out other small capsules for their properties, but it’s more ambitious and I should start small with Electroslusch and Contact Microphone build guides