The Schoeps transformerless buffer circuit
This is by far the most popular transformerless, phantom powered impedance transformer circuit used in condenser microphones. There are many incarnations of this circuit around, with only minor differences. Is there anything that can be improved on this circuit? You bet! And I don’t mean replacing some capacitors and then hoping for Magic to happen. Read more here.
KM84 style charge amplifier circuit
Maybe I didn’t look around the internet properly, but I found surprisingly little in-depth information about the KM84 circuit. This, despite the fact that it is a much-cloned microphone. I investigated the properties of the KM84 a little further and designed my own KM84 variants. In the analysis, I incorporated many simulations, measurements, and some recordings to support the analyses. I hope this helps you if you want to experiment with this circuit yourself.
Components and subcircuits
In a series of articles, I will discuss many components and subcircuits that are found in every, or almost every, condenser microphone. I will also try to examine frequently heard, but not always well-substantiated, opinions for their value. As usual, where possible substantiated with simulations, measurements, or references to known scientific publications, if I could find them.