The problem is obvious: one need to merely listen to the echo and long trailing reverberation in a gymnasium to realize that these venues are not suited for communication. When music is played, the excessive echo caused by the typical concrete brick surfaces renders each note indistinct. This same problem occurs in dance class venues, karate clubs and fitness centers where often times, hard surfaces such as mirrors will be used on the walls, floors will be hardwood and the remaining walls will either be made of gypsum board or covered with windows.
The solution is easy: add Broadway acoustic panels to the walls wherever possible. This will attenuate the reflections and improve intelligibility.
Choosing the type of panel is determined by the type of sound you are trying to control and the available space. The thicker the absorptive panel, the lower the frequency it will control. High frequencies are easy to tame and of course, thinner panels cost less. We usually recommend 2" thick panels to be used for these facilities. Most fitness centers employ a mix between Broadway Control Columns and Broadway Broadband absorbers. These are interspersed throughout the facility with a greater density of panels positioned across from highly reflective surfaces like mirrors to reduce chatter echo.

Greater number of panels are used to control excessive echo caused by hard surfaces like mirrors.
Placing panels so that each parallel surface has some treatment will help reduce flutter echo.
Since most rooms are rectangular, mount the acoustic panels on opposing parallel wall surfaces in such a way that the echo will not sustain itself. This is done by simply drawing a vector across the room and treating one end. The more panels you put up, the quieter and more controlled the room will be.
Adding acoustic treatment will not only reduce ear fatigue for those that are teaching, but will improve communication between those that are in the room and make it easier to learn.
To determine the coverage, we have created a series of easy-to-use tables that enable you to choose between various degrees of treatment depending on your budget and the desired outcome. Most facilities find that a ‘light’ level of treatment provides sufficient sound abatement while keeping the budget in check. If budgets are tight, start with minimal treatment and then add more panels as funds become available.