Correlated sound sources create spatial interference patterns that uncorrelated sources do not.

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 (#expands, via linked claim)

Several acoustical situations can cause interference effects. The obvious ones are when two loudspeakers radiate the same sound into a room or when the same sound is coupled into a room via two openings that are separated. A less obvious situation is when there is a single sound source spaced away from a reflecting boundary, either bounded or unbounded. In this situation, an image source is Position (in wavelengths) or relative frequency FIGURE 1. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 366 (#exemplifies, via linked claim)

Categorization

• XREF: connects to: Correlated sound sources add pressures while uncorrelated ones add energy; Interference pattern of correlated sources varies with both listener position and frequency — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 241; Correlated sound sources sum to between zero and twice their individual amplitudes — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 267 (+8 more)

Broader Connections

• Correlated waves interfere with each other while uncorrelated sources do not #corroborates (0.95)
• Uncorrelated sound waves sum by power, not by amplitude. #expands (0.88) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 244
• A single sound source near a reflecting surface creates interference via an image source #exemplifies (0.75) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 366
• Coincident delayed sounds are far harder to detect than spatially separated ones #expands (0.72)