The heart of the home audio system is the amplifier, which is the element in which the synthesis of the signals coming from source, to transform itself into enhanced electrical impulses directed to the loudspeakers.
Hi-Fi amplifier: what it is and how it works
The amplifier is the element to which the various components of the hi-fi system are connected via cables. The music and the voices from the source are transformed into electric micro-impulses that end up in the amplifier, where they are amplified and transformed into as many impulses that producing sound.
Hi-fi stereo amplifier: types
Several decades ago there were only tube amplifiers. Without going into the technical details, a tube amplifier has a structure made up of “valves”, which serve to increase the electrical voltage of the input signals, while in most of the amplifiers you find on the market the structure is a transistor, elements that increase the input current (not the voltage). You can find a comparison of these two types in most integrated amplifiers reviews.
The disadvantage of tube amplifiers is to be very bulky on average, to heat a lot, and to consume a lot of current. Besides, once turned on, it is necessary to wait a few minutes before it heats up to give the best.
Power and functionality
The ideal would be to coordinate the purchase of the amplifier with that of the loudspeakers because the power of the loudspeakers must be proportionate to that of the amplifier. To power two 50W speakers, for example, a 100W power amplifier would be fine.
If you listen to a lot of music on your PC, smartphone, or tablet, I would think of a product with Bluetooth connectivity as standard, so you can launch the streaming audio from your device and hear it reproduced in high quality on your stereo system.
Finally, if you have an old vintage turntable, check that there is the Phono input, essential because the type of signal produced by the turntables is different from that of the other components and would not work connected to another input, while recent production turntables usually have a small preamplifier that allows you to output a signal similar to that of a CD player or cassettes, therefore they can be connected to the amplifier’s CD, TAPE or AUX inputs without problems.