What solid state amplifiers are

What they are

In electronics, solid state circuits are those that do not contain vacuum tubes. The term was introduced to describe the transition from valve-based amplifiers to transistorised amplifiers. Solid-state components last much longer than their thermionic counterparts because of their greater resistance to shock, vibration and mechanical wear.

As the use of vacuum tubes in consumer electronics has decreased (an exception being the CRT still widely used for TV and desktop computer monitors), the term 'solid state' has been increasingly used as a synonym for no moving parts. For example, digital audio players that store all their songs in flash memory are often described as solid state to differentiate them from hard disk players. Like the older usage, this usage connotes increased durability and shock resistance.

This is a 'standard' amplifier that enforces the sound electronically making use of transistors instead of tubes (valves). A solid state amplifier is a device for increasing the current, voltage or power of a signal. It does this by taking power from a power supply and controlling the output to match the input signal shape but with a larger amplitude. This process invariably introduces some noise and distortion into the signal, and the process cannot be 100% efficient. Therefore amplifiers will always produce some waste heat. An idealized amplifier can be said to be a piece of wire with gain, as the output is an exact replica of the input, but larger.