Rubidium is not typically used in the construction of magnetic speakers. The most common material used in the construction of magnets for speakers is neodymium, which has a high magnetic strength-to-weight ratio.
Neodymium magnets are composed of an alloy of neodymium, iron, and boron, and they are known for their powerful magnetic fields. These magnets are used in a variety of applications, including loudspeakers, headphones, and microphones.
While rubidium is a metallic element with magnetic properties, it is not commonly used in the construction of magnets for speakers. Rubidium is a relatively rare element and is more commonly used in research and industrial applications, such as atomic clocks and laser technology.
In summary, rubidium is not typically used in the construction of magnetic speakers, and neodymium is the most common material used for this purpose.