The SonoColumn is part of the SonoFlat system and a good solution for the absorption of low-frequencies. Works effectively for reducing low frequency build-up. Like the LENRD corner bass traps, SonoColumns are an excellent way to tame low-frequency anomalies in a room while offering a decorative alternative. The four foot long column was designed to be stacked one on top of another, to create an eight foot fluted column that can be placed anywhere on the wall, or in a corner where most bass build-up occurs.