Tomi writes – “This is a simple microphone preamplifier circuit which you can use between your microphone and stereo amplifier. This circuit amplifier microphone suitable for use with normal home stereo amplifier line/CD/aux/tape inputs. This microphone preamplifier can take both dynamic and electret microphone inputs (preamplifier provides power foe electret microphone elements). The idea of this circuit is to keep the design as simple as possible to be easy to build. That was my goal when I needed a simple external microphone preamplifier for my mixer. The performance of the circuit is nothing superior but can be used with many not so serious projects.” Link.