Some Typical Sound Pressure Levels

• 0 dB SPL - Absolute threshold 3-kHz sinusoid free-field

• 40 dB SPL - Very quit living room.

• 60 dB SPL - Average Conversation 5 feet from speaker.

• 80 dB SPL - Same speaker shouting.

• 90-100 dB SPL - Platform of subway station as train arrives.

• 130-150 dB SPL - 100 feet behind airplane jet engine.