Audio Video Receiver

Some people think this item is optional. It is not. It serves many purposes.

It consists of different components put together like the tuner, preamplifier, surround sound decoder, digital signal processor and power amplifier. It is the nerve centre and act as a switch. It directs audio and video signal from source component to its output devices such as Monitors and speakers. Along the way, the signal is processed and amplified. The signal which comes from the source component like DVD player is too weak to drive the speaker. The receiver job is to amplified the signal and send it to the speaker driver.

Preamplifier

It controls the sound volume as well as direct audio and video signals from source components to output devices. These low voltage signals are not able to drive speakers and therefore are sent to the power amplifier section.

Amplifier

The preamplified signal goes through a series of semiconductors such as transistors or even vacuum tubes to boost and increase the amplitude of signal voltage.

The circuitry used in the amplifier section should be of high quality. If it is of inferior quality and insufficient power is provided, the sound comes out distorted at higher volume. Too much power delivered however may cause the speaker to be blown off.

How much power should an amplifier have? Well, 100 watts for each AV channel should be sufficient for the average listener.

The amplifier section should have enough power wattage per channel. Sometimes manufacturers only list system total power wattage. This could mean some channels get higher power output than others, thus resulting in a poorer sound quality. Wattage must also be considered under what the frequency range and speaker load.

It is paramount to get a receiver with a good power supply design. During a movie with a long period of explosion and mayhem, poorer quality receivers are unable to sustain or meet the requirement of high power output levels for a prolonged period.

Of course, quality should not be defined by the quantity of wattage.

Besides that, you need to consider the THD which is the total harmonic distortion. This is the amount of harmonic distortion in the total musical signal. You should ideally look for a number below 0.05% THD.