Level Up Your Audio With Phantom Power!
There are many types of microphones out there, and you may have noticed that the boom mic on your gaming headset works well enough to shout at your squadmates when gaming, but not so much when having a long conversation with friends or family over your videoconferencing app of choice.
Our podcast makes use of a mix of cardiod condenser microphones from Monoproce and glowing red electret condenser mics from HyperX. Ignoring the various challenges that our software gifts us with on the podcast, that is a very good demonstration of the difference between the two types. The condenser mic has a floating diaphragm which is used as part of the capacitor, and sound vibrations make it vibrate, moving closer and further from the second part of the electrode, which is how the audio is captured and sent to the PC and on to you. It requires an external power source to charge the diaphragm, in our case USB, with XLR offering better audio performance overall.
An electret microphone is also a condenser mic, but instead of a diaphragm it uses a permanently polarized piece of ferroelectric material. This makes it more robust, unless you bash it so hard and frequently you managed to change the polarization, and offers a much flatter response due to the material as well. Electret microphones started out being fairly low quality but have vastly improved over the years and if you add a preamp into the microphone along with some phantom power you will end up with something every bit as good as a cardiod mic, at a lower cost.
This all leads to a post over at Hackaday, which features a project that will teach you how to make your own high quality electret microphone with relatively easy to source components. It makes use of dual OPA1642 op-amps to provide high quality sound and remove the need for a battery pack. If you are interested it is a great way to not only get a high quality microphone for your video calls, not to mention a unique looking one as well.
The circuit is designed to fit inside a common BM700 or BM800 microphone body, and the PCB can be ordered from PCBWay for those interested in building their own. There’s also a saddle on Shapeways that’s designed to neatly mount the electret capsule within the housing.