As supplied by power companies, AC in the United States alternates 60 times per second and is deemed as 60 Hz power. Ampere is a unit measurement of current of electrical energy equal to one coulomb of charge per second. The electrons in a circuit flow in the opposite direction as the current itself. Amplifier A device, either a single stage or a large scale circuit with mutiple stages for creating gain, ie. making small signals larger. Amplification Classes .
All sound is a sinosoidial waveform.
It has alternating peaks and valleys. When a tube or transistor amplifier operates in Class A , the output tubes or transistors amplify the entire waveform without splitting it into positive and negative halves. In Class AB , used in the overwhelming majority of amplifier designs, the signal is split into two halves, positive and negative, and each half is sent to a tube or transistor circuit for amplification. Both sides work in tandem, and the two halves are recombined at the output section to reconstruct the whole signal. This technique increases the amount of power that can be applied, but increases distortion.