Читать книгу Engineering Acoustics - Malcolm J. Crocker - Страница 94

If p₁ = p₂ = 1 Pa and the two sound pressures are of the same amplitude and frequency, but in opposite phase with each other, then the total sound pressure level

For such a case as in Example 3.2 above, for pure tone sounds, instead of 83 dB, the total sound pressure level can range anywhere between 86 dB (for in‐phase sound pressures) and −∞ dB (for out‐of‐phase sound pressures). For the Example 3.3 above, the total sound power radiated by the two pure‐tone sources depends on the phasing and separation distance.