apparent increase in loudness (Leon van Noorden )

Subject: apparent increase in loudness
From:    Leon van Noorden  <leonvannoorden(at)CHELLO.BE>
Date:    Thu, 29 Jan 2004 20:35:34 +0100

auditorylist,

during a recent transatlantic flight I observed
the phenomenon that the sound of a crying baby
appeared louder when I tried to mask it by
putting on a headphone with loud instrumental music.
It ran against my expectation that a partially
masked sound would appear less loud.
Is this a known phenomenon?

Leon van Noorden