Category: Rehearsal Rooms
Published on Friday, 15 January 2010 17:41
Written by Bruce Gale
Rehearsal rooms invariably benefit from attempts to deaden the sound. In fact, such rooms should ideally be almost as dead as possible, with little or no echo. In most schools and colleges in Southeast Asia, however, rehearsal rooms are usually converted classrooms.
Rehearsal rooms invariably benefit from attempts to deaden the sound. In fact, such rooms should ideally be almost as dead as possible, with little or no echo. In most schools and colleges in Southeast Asia, however, rehearsal rooms are usually converted classrooms. Typically, they are characterized by cement floors, brick walls, and ceilings made of similarly inappropriate material. When these areas are used as practice rooms, the resulting echoes produce a sort of musical fog that make it almost impossible to check the ensemble for balance, intonation, or even wrong notes!
If your institution cannot afford carpet or thick wall drapes, try spreading large rugs or mats on the floor and placing second-hand, thickly padded furniture around the room. Thickness is important. Thin felt on concrete absorbs only about 25% of the sound at 500Hz. Thick pile carpet placed on the same concrete, on the other hand, can absorb up to 50% of the sound. [See the table on "Absorption Coefficients at Different Frequencies" given in concert halls]. The containers used to package eggs sold in supermarkets can also be used to cut down the sound reflected from brick walls. Suitably painted, they can be attached to the walls in batches to form attractive abstract designs. Get the school’s art department to suggest some ideas.
If you are still facing problems, consider the significance of careful positioning. Even a thin curtain placed about six inches away from a brick or concrete wall will block more reflected sound than a thick curtain hung directly in front of it. Curtains do not always need to be heavy to be effective. Open weave material -- if you can find it -- is generally better at absorbing sound.
Even the way in which a rehearsal room is painted can be important. Strangely enough, a porous brick surface can have its sound absorption ability raised by 15% by one coat of paint applied with a brush or lowered by 20% by one coat of paint applied with a roller. Use a brush whenever possible.
The principles of acoustics and their application to architecture are so well known these days that some very fine concert halls have been constructed in recent years in both Asia and the West. One of the best in Southeast Asia is situated in the Petronas Towers in Kuala Lumpur and is home to the Malaysian Philharmonic Orchestra. Fortunately, it is not necessary to be an architect or audio engineer to know how to avoid the most common acoustical errors when constructing or renovating a building. Study the principles outlined here, experiment a little, and you will be well on your way to ensuring that both your rehearsal room and the concert hall in your community is of reasonable quality.
(See how the Medan Band prepared their rehearsal room. Click here. )