 The manufacture of residence or "chamber" organs to provide entertainment in the mansions of millionaires was an extremely profitable undertaking, and Aeolian virtually cornered the market in this trade, freeing them from the tight competition of church-organ building with its narrow profit margins.Elaborate cases and consoles were often featured in residence organs.In other installations, the pipes were hidden behind tapestries, under or above staircases, or spoke from the basement through grilles or tone chutes.