Waltrip Challenge

A few companies, including Victor Talking Apparatus Company and Pathe, produced annals players using compressed-air loudspeakers. However, these designs were significantly limited by their poor sound endowment and their inability to reproduce stable at low volume. Variants of the integrate were not new for metropolitan address applications, and Wireless Speakers another recently other variations have been given to to test amplitude equipment resistance to the pure loud sound and vibration levels that launching rockets produce.

Very few manufacturers adoption electrically powered field coils as was hackneyed in the earliest designs. The capaciousness and type of magnet and details of the magnetic circuit differ, depending on conception goals. For instance, the shape of the pole piece affects the magnetic interaction between the voice coil and the magnetic field, and is sometimes used to modify a driver's behavior. As well, a 'shorting ring' or cap is sometimes dedicated near the magnetic gap to reduce adverse distortion effects of aerial faddy in the voice coil.