A stereo speaker amplifier is a device that can be connected to a stereo with separate speakers to boost the signal or power of those speakers. Different devices can be used and set up in a variety of ways, though generally they can be connected either individually to each speaker or to the entire system as one unit. The purpose of a stereo speaker amplifier is typically to boost some type of signal received by a speaker. Either the power or the audio signal to the speaker can be amplified, which typically results in clearer sound quality or louder audio playback.
Although there are a number of devices that can be used as a stereo speaker amplifier or amp, most of them are meant to improve upon a signal rather than simply passing it along. Most stereo systems include a signal receiver, which is typically connected to devices that play media or receives a radio signal. This receiver often has an amplifier built into it, which is used to boost the received signal and send it to speakers for playback. A system that does not have a built-in amp, however, can use a stereo speaker amplifier to boost the audio signal that is sent to the speakers.
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This type of stereo speaker amplifier is typically used as part of a sound system that does not include a receiver, such as a system in which a television can be connected to external speakers. The use of an amplifier allows someone to ensure that audio sent to the speakers is of high quality. This type of stereo speaker amplifier can also allow someone to reach higher volumes through his or her speakers, though care should be exercised for this purpose to avoid damaging the speakers. Anyone with multiple speaker setups, such as a system with speakers inside and outdoors, may be able to use an amplifier to boost the signal to those outdoors.
A stereo speaker amplifier may also allow a listener to have multiple setups connected through a single system. These devices often have switches that allow a person to have two different input devices or multiple speaker configurations all connected together through a single setup. Someone can then use the stereo speaker amplifier to control which input source is used to send an audio signal to the connected speakers. Multiple speaker setups can also be used with a switch allowing a listener to adjust which set of speakers the signal is sent to, which is then boosted by the amp for optimal audio quality during playback.