Monthly Archives: September 2015

A Quick Look at Digital Audio Amplifiers

Audio power amplifiers are the core element between your source and speakers. They are required in order to drive speakers which have a very low impedance with a high voltage swing. If you were to connect speakers directly to a source then the source most likely would take some damage. Therefore an amplifier not only boosts the signal sufficiently to achieve the desired volume on a set of speakers but also it serves as the protection for your source. The way audio amplifiers work is changed quite a bit in the last decade. I’m going to explain how amplifiers work and what has changed in the last few years.

Nowadays the bulk of audio amplifiers works by using digital modulation. The core element of these switch mode amplifiers is a pair of complementary transistors. These transistors are switched on and off repeatedly. Even if the audio input signal doesn’t change, these transistors are switched constantly. Once there is an audio signal applied to the input of the amplifier, the signal which is modulating the power stage changes. This a change in time of the switching signal is either analog or digital. The frequency of the switching signal also might change depending on the technology.

some decent wireless speakers

Obviously, connecting the output of this …