Diffuse rear reflections blend instruments while specular ones create hot spots

Evidence

The usual compromise is to make use of the sound that radiates behind the performers and direct it out to the audience via the performers, as shown in Figure 6.28. This has the twofold advantage of providing the performers with acoustic foldback and redirecting sound energy that might have been lost back to the audience. Ideally, the sound that is redirected back to the performers should be diffuse, as this will blend the sounds of the different instruments together for all the performers, as shown in Figure 6.29, whereas specular reflectors can have hot and cold spots for a given instrument on the stage. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1937

Categorization

• DEFINE: Distinguishes diffuse from specular reflection by the perceptual consequence — blending versus hot/cold spots.
• XREF: connects to: Diffuse reflections help integrate and blend acoustic instrument sound — David Howard, Jamie Angus, coustics and Psychoacoustics, 2317