๐ Decibel Difference Calculator
Pressure ratio = 10^(differenceรท20), Power ratio = 10^(differenceรท10)
Enter two sound pressure levels (dB SPL) to calculate the difference between them in dB, along with the corresponding sound pressure ratio and acoustic power (intensity) ratio. Handy for comparing audio equipment specs or roughly gauging the effect of soundproofing.
How to use
- Enter the two sound pressure levels (dB) you want to compare.
- The dB difference, pressure ratio, and power ratio are calculated automatically.
FAQ
What's the difference between pressure ratio and power ratio?
Sound pressure level is defined as 20รlog10(ratio), while sound power (intensity) level is 10รlog10(ratio), so the same dB difference maps to different ratios. For example, +6dB is roughly a 2x pressure ratio but about a 4x power ratio.
How big a difference is +10dB?
+10dB is exactly a 10x power ratio, and about a 3.16x pressure ratio. As a rule of thumb in acoustic engineering, a change of about +10dB is perceived by human hearing as roughly "twice as loud."
Can I enter a negative value?
Yes. If dB B is smaller, the difference comes out negative and the ratios are calculated as less than 1 (a decrease in level).