Correlated sound sources add pressures while uncorrelated ones add energy

Evidence

On the other hand, if the sound waves are uncorrelated, then they do not add algebraically, like correlated waves; instead, we must add the powers of the individual waves together. As stated earlier, the power in a waveform is proportional to the square of the pressure levels, so in order to sum the powers of the waves, we must square the pressure amplitudes before adding them together. If we want the result as a pressure, then we must take the square root of the result. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 244 (#corroborates, via linked claim)

Categorization

• corroborated: 2 independent passages support this claim
• XREF: connects to: Adjacent in-phase sources boost each piston’s efficiency N-fold through mutual pressure; Sound power and intensity levels are unaffected by source correlation, unlike pressure level; Correlated sound sources sum to between zero and twice their individual amplitudes (+8 more)

Related

• Correlated sound sources sum to between zero and twice their individual amplitudes (similarity 0.96)
• Adding uncorrelated sound sources raises level as the square root of their number (similarity 0.94)
• Uncorrelated sound waves sum by power, not by amplitude. (similarity 0.94)
• Correlated source summation swings from zero to twice amplitude by frequency (similarity 0.93)
• Correlated sound sources create spatial interference patterns that uncorrelated sources do not. (similarity 0.93)
• Two equal uncorrelated sound sources add only 3 decibels. (similarity 0.93)
• Uncorrelated source totals ignore the relative phases of signals. (similarity 0.91)
• Correlated sound sources combine by direct pressure addition (similarity 0.90)
• Mutual resonance between sources boosts combined power beyond their sum (similarity 0.88)
• Interfering sound waves pass through each other because their energy flow is preserved (similarity 0.88)
• Sound power and intensity levels are unaffected by source correlation, unlike pressure level (similarity 0.85)
• Adding sound levels differs depending on whether sources are correlated or not. (similarity 0.85)
• Even identical instruments playing in unison produce uncorrelated waveforms. (similarity 0.84)
• Interference pattern of correlated sources varies with both listener position and frequency (similarity 0.84)
• Uncorrelated source addition ignores phase and depends only on signal power. (similarity 0.82)

Broader Connections

• Sound power and intensity levels are unaffected by source correlation, unlike pressure level #expands (0.90)
• Uncorrelated sound waves sum by power, not by amplitude. #corroborates (0.90) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 244
• Correlated sound sources sum to between zero and twice their individual amplitudes #expands (0.85)
• Correlated waves interfere with each other while uncorrelated sources do not #expands (0.85)
• Correlated sound sources create spatial interference patterns that uncorrelated sources do not. #expands (0.80)
• Adding uncorrelated sound sources raises level as the square root of their number #expands (0.80)
• Interference pattern of correlated sources varies with both listener position and frequency #expands (0.75)