A speaker is used to convert electrical signals to audible signals. Nonelectrical loudspeakers were created as accessories for phone systems, but loudspeakers were made useful by electronic amplification by vacuum tube. Dynamic speaker is the most popular of all the speakers. As a dynamic microphone this speaker is also operated on the same principles. Where high loyalty replication of sound is required, many loudspeakers may be utilized, each creating a part of the audible frequency range. In devices such as TV receivers, radio and many sorts of music players have Miniature loudspeakers. A larger speaker systems are used for audio, music reinforcement in concerts and theatres, and also in public address systems. Loudspeakers are usually housed in an enclosure that is often a square or rectangular box made of plastic or sometimes wood.
There are various types of speakers available online for consumer use. Some speakers have additional option for subwoofers while some have an extra output for docked media devices and mobile phones. Speakers are commonly used with mp3 players, iPods, iPhones, TV and memory cards.
Speakers these days are also available with Wi-Fi connectivity option for transferring media files and are remote controlled with voice recognition enabled.