免费声压级计算器
计算声压级(SPL)，以分贝为单位。
Pa
Sound Pressure Level
94.0 dB SPL
Sound Pressure Level vs RMS Sound Pressure
公式
Sound Pressure Level (SPL)
SPL quantifies the RMS sound pressure relative to the threshold of hearing on a logarithmic scale.
Formula
SPL = 20 * log10(p / p_0)
where p_0 = 20 micro-Pa = 2 x 10^-5 Pa is the reference pressure corresponding to the threshold of human hearing at 1 kHz.
计算示例
A sound wave with RMS pressure of 1 Pa.
- 01SPL = 20 * log10(p / p_0)
- 02SPL = 20 * log10(1 / 0.00002)
- 03SPL = 20 * log10(50000)
- 04SPL = 20 * 4.699 = 94.0 dB SPL
常见问题
What is the reference pressure p0?
20 micro-pascals (2 x 10^-5 Pa), chosen to match the approximate threshold of human hearing at 1 kHz.
How does SPL relate to sound intensity level?
Both use dB but SPL uses pressure (20 * log10) while intensity level uses power (10 * log10). They yield the same numeric value under standard conditions.
What is a typical SPL for conversation?
Normal conversation at 1 meter is about 60 to 70 dB SPL.
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