Useful Reflections

Reflections are an important part of acoustical design for music performance venues. For effective musical acoustics, the reflections have to arrive within the correct time window, and from the correct direction. The reflections help to boost the level of acoustic instruments and human voices in the audience area. They also influence timbre and help define the apparent size or perspective of the instruments. The critical time interval we're talking about is a very brief 0.3 seconds (less than a third of a second) after the direct path for sound from the instrument. And the time interval that determines the apparent location, size and timbre of the instruments or voices is even shorter, between 0.01 and 0.08 seconds. By carefully tailoring the wall and ceiling shapes of a music venue, we can provide the correct balance of reflections from the side walls and ceiling surfaces, arriving at the correct times to maintain the "aspect ratio" of the music (kind of like sizing the window in the net browser you're using now), and to keep the instruments in their correct location on stage. It wouldn't do to have the violin appear to be on the opposite side of the stage. There are technical descriptors and well established criterion for these values, which are known by terms like "Clarity", "Initial Time Delay Gap", "Early/Late Ratio", and "Lateral Fraction".

Direct + Reflected Sound Direct Only Direct+1st Order Direct+2nd Order Direct+3rd Order

The reflecting surfaces need to provide a smooth and uniform blend of the instruments on the stage, so that the audience can hear an orchestra or ensemble rather than several solo musicians. Careful design of reflecting surfaces provide this blending of sound, without blurring the location or altering the apparent size or perspective of the instruments.

The audience isn't the only benefactor from useful reflections. The musicians need to hear themselves and each other to stay on pitch and in time. They also need to be able to tell how loud they're playing or singing in relation to each other. The shaping and position of reflecting surfaces on the stage are critical for the musicians. If the surfaces are too far away, timing can suffer. If the surfaces are too close, the reflection can be too loud, fooling the musician into believing they are playing too loud. We apply a combination of reflectors, absorbers and diffusers to balance the stage environment for the musicians.