Speech synthesis is the artificial production of human speech.

A computer system used for this purpose is called a speech computer or speech synthesizer, and can be implemented in software or hardware products.

A text-to-speech (TTS) system converts normal language text into speech; other systems render symbolic linguistic representations like phonetic transcriptions into speech.

A transformer is a static electrical device that transfers electrical energy between two or more circuits through electromagnetic induction.

A varying current in one coil of the transformer produces a varying magnetic field, which in turn induces a varying electromotive force (emf) or "voltage" in a second coil.

Power can be transferred between the two coils, without a metallic connection between the two circuits.

Faraday's law of induction discovered in 1831 described this effect.

Transformers are used to increase or decrease the alternating voltages in electric power applications.

A robot is a machine—especially one programmable by a computer— capable of carrying out a complex series of actions automatically.

Robots can be guided by an external control device or the control may be embedded within.

Robots may be constructed to take on human form but most robots are machines designed to perform a task with no regard to how they look.

In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the carrier signal, with a modulating signal that typically contains information to be transmitted.

Most radio systems in the 20th century used frequency modulation (FM) or amplitude modulation (AM) to make the carrier carry the radio broadcast.

An amplifier, electronic amplifier or (informally) amp is an electronic device that can increase the power of a signal (a time-varying voltage or current).

It is a two-port electronic circuit that uses electric power from a power supply to increase the amplitude of a signal applied to its input terminals, producing a proportionally greater amplitude signal at its output.

The amount of amplification provided by an amplifier is measured by its gain: the ratio of output voltage, current, or power to input.

An amplifier is a circuit that has a power gain greater than one.