SW1X Audio Design™ PRE II Performance Level 2 Line Pre-Amplifier   The PRE II is a pure class A, Output Transfomerless (OTL) line pre-amplifier with Power Valve Output Stage. Employing 6V6 power tubes at the output makes the PRE II a smaller brother to the SW1X PRE IV pre-amplifier. It is great enhancement to any … Continue reading SW1X PRE II Line Pre-Amplifier