Summit Audio TPA-200B Dual Channel Tube Mic/Instrument PreamplifierThe Summit Audio TPA 200B is an incredibly easy to use dual channel preamplifier marrying a classic tube and transformer front end design with a more modern solid state output stage, resulting in ultra clean gain that really lets the warmth and rich harmonic detail of the tube come through. The TPA 200B allows you to set gain clean and pristine or layer tube input saturation all the way to thick harmonic distortion with all sorts of variations in