A few companies, including Victor Talking Agency Community and Pathe, produced documentation players using compressed-air loudspeakers. However, these designs were significantly constrained by their poor sound affection and their inability to reproduce sound at low volume. Variants of the system were used for intermutual address applications, and more recently other IPOD Speakers variations have been familiar with to confirmation space equipment resistance to the very loud safe and vibration levels that launching rockets produce.
The basket or frame must be designed for rigidity to avoid deformation, which will paper money the magnetic conditions in the magnet gap, and could even cause the tone coil to swab against the walls of the magnetic gap. Baskets are altogether cast or stamped metal, although molded plastic baskets are becoming common, especially for inexpensive drivers. The frame also plays a considerable role in conducting heat away from the coil.