Usually the audio equipments that meets this standard can be said a hi-fi system, but in general, the hi-fi term is highly misused to equipments that do not even refer the DIN standards. The frequencies reproduced by the audio equipments should be able to toggle between high and low in-order to be realistic. The frequency range used by the equipment should provide no noticeable distortion of the signal or emphasis or de-emphasis. The modern equipment at a relatively moderate cost can satisfy all the requirements except for its low realism.

The term high fidelity were used by people involved in making audio equipments in the 1950s as an attracting term for people to describe records and equipment which were aimed at providing high quality sound reproduction. Some consumers were highly attracted to the high fidelity systems as fancy and expensive equipment, many felt the difference in quality between hi-fi and the other audio equipments.

The technical characteristics and the individual components such as pre-amplifiers, loudspeakers, power amplifiers were taken care of in the hi-fi systems. Even some people tried to aggregate their own audio systems. The terms phonograph and recorders were beginning to be replaced by the term hi-fi.

A very well known format of a system in 1970s consisted of all the individual components like power amplifier, radio tuner, tape player, pre-amplifier and phonograph were given in a single package with removable or attachable speakers. These equipments were known for their simplicity because there was no need for assembling individual components instead all the components were integrated and sold. People who believe in conventional method for audio reproduction will resist the use of the term hi-fi even though the system produces high quality audio output.

In a concert hall the high fidelity when compressed to monophonic sound reproduction, a realistic feeling that the customer will feel will be limited. Then the general quality and clarity of the sound will not be any less than the stereophonic sound reproduction.

People doing the researches swiftly understood that the best method to realize music played back on audio systems is by using multiple audio transmission and reception channels, but at that time, the technology was not available. Accidently, the researchers discovered that the realistic or original representation of the segregation in between the performers in the stage from an ideal listening position in the concert hall will need three loudspeakers in front of the channels and for the process of reverberation reproduction we require two speakers placed to the sides or even behind the listeners whenever the necessity arises.

The use of stereophonic speakers gives us a good solution to the process of creating some resemblance of the illusion of the performers by making use of a middle channel when the listener is placed exactly at the center of the two front speakers. Whenever the listener goes slightly towards the side, this center channel known as the phantom channel either disappears or gets highly suppressed. In-order to provide for the process of reverberation reproduction was trailed during the 1970s by means of quadraphonic sound, but this technology was insufficient to match to the required task. The users were against paying increased money for small improvements in realism of high quality audio reproduction.

Nowadays a modern hi-fi system can consist of signal sources like digital audio tape, High Definition radio tuners and Digital Audio Broadcasting . All modern hi-fi systems can be connected using fiber optic cables to an universal serial bus ports, even including one to play digital audio files and to a Wi-Fi network.

The major development in the hi-fi systems is the use of the music server which has one or more computer hard disks that stores audio in the form of computer files. If the audio that is stored in an audio file format such as WMV, WMA Lossless, then the computer playback of recorded audio can work as an high-quality source for the hi-fi system.

Another big advantage of this modulation is ability of the user to spend money on a few core components initially and then add additional components to his system. Thus the modular way of building a hi-fi system is an easier method because of those fore mentioned advantages. There are some disadvantages of this method such as high cost and complexity and also the system occupies larger space.