Adding equal sound intensities yields a 3 dB total increment

Evidence

For equal sound pressure level L1 = L2, we reach an increment 11L = 3 dB; for a difference L1 - L2 = 2 dB, we get 11L of about 2 dB; for L1 - L2 = 6 dB, the increment is only 1 dB. For differences L1 - L2 larger than 10 dB, the influence of L2 can be ignored in most of the cases. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1329

Categorization

Category: Factual Claims

• QUESTION: Worth verifying how this intensity-addition rule relates to perceptual loudness addition versus physical power summation.

Related

• Adding sound intensities of equal level yields only a three-decibel increase (similarity 0.92)
• Two equal uncorrelated sound sources add only 3 decibels. (similarity 0.84)
• Decibel sound levels cannot be added directly because they are logarithmic (similarity 0.83)
• Decibel sound levels cannot be added directly because sound powers combine, not levels (similarity 0.83)
• Each added boundary surface boosts sound intensity by 3 dB up to three boundaries (similarity 0.82)
• Adding sound levels differs depending on whether sources are correlated or not. (similarity 0.81)
• A 10 dB increase always doubles perceived loudness above 40 dB (similarity 0.81)
• Doubling loudness requires 10 dB, not 3 dB or 6 dB (similarity 0.80)
• Coherent sound addition yields double the amplitude gain of incoherent addition (similarity 0.80)
• Decibel values must be converted to ratios before they can be added (similarity 0.80)
• Loudness perception requires a tenfold intensity increase to double (similarity 0.80)
• Two equal uncorrelated sources raise level less than two correlated ones. (similarity 0.79)
• Doubling pressure yields 6 dB and a tenfold increase yields 20 dB. (similarity 0.79)
• Each 10 dB of level requires ten times the amplifier power (similarity 0.79)
• Adding uncorrelated sound sources raises level as the square root of their number (similarity 0.79)

Broader Connections

• Two equal uncorrelated sound sources add only 3 decibels. #corroborates (1.00) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 297
• Adding uncorrelated sound sources raises level as the square root of their number #qualifies (0.85) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 272
• Each added boundary surface boosts sound intensity by 3 dB up to three boundaries #expands (0.70) — David Howard, Jamie Angus, coustics and Psychoacoustics, 313