Hi-Fi is a term often used by home audio enthusiasts and audiophiles, meaning high-fidelity replay sounds that are highly similar to the original sound.
From an audio professional perspective, it is required that the sound system has a sufficiently high signal-to-noise ratio at the rated output power, the waveform is sufficiently low in distortion compared to the input signal, and has a frequency response that is wide enough and has no significant fluctuations in the range.
Hi-Fi audio system consists of six important parts: power supply, sound source, pre-amplifier, post-amplifier (amplifier), speaker (speaker), and cable connectors.
A power supply is a device that supplies power to the entire sound system. In the Hi-Fi field, there are certain requirements for the purity of the power supply, and functions such as filtering and voltage regulation are often used.
The power amplifier (power amplifier) is mainly to amplify the weak signal input by the sound source equipment and generate a large enough current to push the speaker to reproduce the sound. There are many types of power amplifiers, which can be divided into pre-stage and post-stage according to function;
The front stage mainly realizes voltage amplification, that is, the weak signal output from the sound source is amplified to the linear range of the power amplifier stage input.
The rear stage realizes the amplification of voltage and current, and the goal is to output a sufficiently strong current to drive the speaker or headphones.
The device used in the amplifier circuit can be a tube or a transistor. The power amplifier made of a tube is commonly known as a "tube amplifier", and the transistor is commonly known as a "stone machine", or two components can be mixed;
According to different circuit designs, power amplifiers can be divided into Class A amplifiers (also known as Class A, "linear amplification"), Class B amplifiers (also known as Class B, "push-pull"), Class A and B amplifiers (also known as Class AB) and Class D amplifier (also known as class D, "switching" or "digital" amplifier). The distortion and efficiency of several circuit forms are very different.
The sound box is the sound-generating part of a set of audio equipment. The final sound of the sound source depends on the sound box to express. The quality of the sound reproduction of the sound equipment is completely expressed by the sound box.
There is no need to explain the wire and connection. Generally, manufacturers of sound sources and amplifiers will launch a set of combined products. The products of the same series can achieve the best balance in overall performance, timbre, coordination and appearance.
A complete set of Hi-Fi audio system is like this.