What is dB SPL?
The term “dB SPL ” is a measurement of Sound Pressure Level (SPL) which is the force that acoustical sound waves apply to air particles. As a person talks or sings, SPL is strongest near the mouth and weakens as the acoustical waves move away from the person. As reference levels, 0 dB SPL is the quietest sound a human can normally hear and 1 dB is the smallest change in level that the human ear can detect. For comparison, at three feet, speech conversation level is about 60 dB SPL and a jackhammer’s level is about 120 dB SPL. What about dB SPL input levels? Microphone manufacturers normally specify one of two dB SPL input levels: 74 dB SPL or 94 dB SPL. Shure uses 74 dB SPL unless indicated otherwise on the data sheet. How do these dB SPL values relate to the real world? 74 dB SPL is typical of the sound intensity twelve inches away from a talker. 94 dB SPL is typical of the sound intensity one inch away from the same talker. A microphone “hears” these sound intensities and converts th
The term “dB SPL” is the unit used to indicate the power of ambient sound. “dB” is the abbreviation of decibels (ten bels), which is the logarithmic ratio of a signal versus a reference level “SPL” indicates the reference level and stands for “Sound Pressure Level”. The reference level is an air pressure of 20 micropascal (0.00002 Pa = 0 dB SPL). Some indicative values: 30-40 dB SPL : ambient room noise / whispering 50-70 dB SPL : normal conversation 80-90 dB SPL : feature film soundtrack in a theater 90-110 dB SPL : busy bar with live music (Swiss legal max is 110 dB in a public arena) 110-120 dB SPL : heavy rock concert 130-140 dB SPL : Threshold of pain for the human ear If the gain of the microphone is correctly set, the ARES-P II+ / ARES-BB+ could be used as a sonometer. The value indicated by the modulometer of the ARES-P II+ / ARES-BB+ is the peak value (dB SPLpeak). The peak value is typically 10 dB higher than the RMS (Root Mean Square) value. Examples: • Input attenuation set
