Large antique horn loudspeaker from 1927 electrical engineering magazine, with girl sitting in mouth to show the scale. Before cone-type loudspeakers took over around 1930, radios and phonographs used horn loudspeakers, because they were more efficient; they could produce ~10 dB (10 times) more sound power from the low power vacuum tubes then in use. However to reproduce bass frequencies adequately the horn had to have a large mouth and long sound path, at least 6 feet long. The walls are made of a heavy composition material, often cloth impregnated with cement, so they do not vibrate and resonate when the sound passes through them. This was a high fidelity speaker probably used either in a theater or a large expensive cabinet type radio. The speaker tube is 10 feet long, wrapped around the horn body, and the unit weighed 185 lb.