Back in the mists of time, I made a set of binaural microphones by removing the small speaker in some in-ear earphones and soldering in some cheap electret microphone modules. The results were excellent generally, with the caveat that they were attached to my head so they did capture my breathing. At the other end of binaural experimentation, lots of people tend to stick microphones to head-shaped objects – a football, a balloon or better, a foam dummy head. This is great but often lacks the actual ear geometry that some binaural purists really want. The BIMINI is a microphone setup that solves all of this with an amazing pair of fake silicon ears added to an interesting PCB microphone module.
Binaural microphones, for those not familiar, are microphones designed to record sound the same way human ears do. By placing the microphones the correct distance apart, and having ear-shaped guides for the sound, it creates a natural three-dimensional recording that when listened to with headphones tricks your brain into feeling like you are in the location where the recording was made! It’s a very interesting recording technique, and if you’ve never heard it, grab a good pair of headphones and do some searching online.
This product hails from Japan and there isn’t a lot of detail on the product page. There is a link to a repository with schematic information and we can see that the PCB has two MEMS microphone modules on board. The enclosure has gaps to mount the two silicon ears which emulate the final journey of sound waves to the eardrum. It’s definitely more compact than carrying a large full foam head but we imagine you might still draw a little attention! There are separate jack sockets for each microphone channel output but the device also runs via USB-C meaning that binaural capture can be achieved with a decent recording app on your USB-C host-capable phone.
Finally, as a slight warning, there is a small video clip where we think they are demonstrating recording an “in-ear” noise of a cotton bud being inserted into the fake ear canal… perhaps it’s just us, but it makes us a little squeamish!