Simple, easy to use audio tool to calculate a loudspeakers sound pressure level (SPL) based on the Inverse Square Law. Two conditions are required or assumed: 1. Free Field Conditions (No Walls or Reflective Surfaces) and 2. Single Point Source. The variables include the distance between the loudspeaker and listener, the desired amplifier power, and the loudspeakers sensitivity rating (usually between 88 to 102 dB defined as 1Watt at 1 Meter). Use the sliders to adjust variable settings on the fly to get quick estimations.