The Hafler PH50 is a high-performance phono stage for moving magnet (dynamic) cartridges that incorporates a well defined RIAA curve to preserve and transmit the original program material with minimal coloration. Particular attention has been applied to reducing noise, a problem common to the 33 RPM recording chain, resulting in a low -82dB noise floor with greater than 91dB of dynamic range and less than 0.002% distortion. The design begins with a 14 gauge steel casing to shield the low level signals from external magnetic fields and RF contamination. Gold-plated input and output RCA connector pairs are employed that will not tarnish over time, thus optimizing signal flow. Inside, the solid-state circuit and military grade PC board have been optimized by carefully positioning parts for minimal self-noise and cross-talk and then supplemented with a ground plane to reduce susceptibility to RF. An external supply further reduces noise by removing the power transformer from inside the casing. Front panel controls include a power on-off switch and a variable low-cut filter that may be inserted into the signal path when needed. The fully adjustable low cut (high-pass) filter enables the user to reduce low frequencies that can cause resonance and feedback when playing music at higher levels. This helps eliminate both airborne and solidly coupled transmission of vibrations that can disrupt the stylus and cause feedback, rumble and distortion. Compact yet ‘plug and play’ easy to use, the PH50 follows Hafler’s 50 year tradition of building the very finest audio products.