sE Electronics DM2 TNT Active In-Line Microphone Preamplifier Dynamite Active In-line Mic Preamp with Selectable Gain and Impedance The DM2 TNT Active In-Line Microphone Preamplifier from sE Electronics is intended to be inserted between a passive ribbon or dynamic microphone and a microphone preamplifier (sold separately) to provide gain for the microphone signal. A switch allows you to select between 15 and 30 dB of gain to boost the audio signal, improving the level to