Like a ship with no captain, a home theater unit without a receiver is lost. An audio receiver runs an entire home audio entertainment system.

The Amplifier
The amplifier deals with the power of the system and amplifies signals from all components (products that you can add to the system).

The Pre-Amplifier
The pre-amplifier controls the amplifier. It provides volume and tone adjustment controls. There are input ports for adding components that you wish to play through your sound system (i.e. CD Player, Cassette Deck, Turntable, TV, etc) and a selector control to choose which component you wish to listen. Other controls may deal with the routing of output signals from components to speakers. Speakers and connecting speaker wire are required for listening. Many models of receivers also include a headphone jack, which allows listening to your system, in complete privacy, using a set of stereo headphones.

The Tuner
The tuner receives radio stations. Most receivers have digitally-tuned AM/FM tuners. This means that you can accurately tune a station according to its specific channel frequency for optimal reception. Digital tuning also gives you the added convenience of being able to pre-select a certain number of your favorite radio stations for easy access when you want to listen.

If you bought a portable or desktop sound system, you’ll find that it consists of several different products that have been integrated (assembled together) into one compact system. It may have a single or double cassette tape deck, a CD player, a radio, and may come with 2 or 5 speakers, either built-in or separate. The system may sound very good but you don’t have the opportunity to individually select those products, according to your individual tastes. In a compact, integrated audio system, the people at the manufacturer’s factory have already chosen everything. It’s a simple way to enjoy music, but you have no choice in selecting any of the products that have been included.

In creating a component sound system, you have the freedom to make an almost infinite number of choices. You can choose among many Cassette Decks, CD Players, CD Recorders, MiniDisc Players, DVD Players, Videocassette Recorders, Televisions, even computers and videogame consoles, that you may wish to attach to the Receiver or Amplifier that you choose. You can listen to dozens, even hundreds, of speaker systems to distinguish which models deliver the sound qualities that are most pleasing to your ears. You can select whatever components you wish to connect and have the liberty to add and remove components according to your changes in tastes or needs.

Although component systems may require a larger investment than a compact system, components may always be selectively changed or upgraded, whereas you’re stuck with all the pre-selected products found in a compact system.

Every receiver delivers a certain amount of watts to all connecting speakers. The "watts per channel" rate has less to do with how loud speakers can get than it has to do with clarity of sound. However, before buying a receiver that delivers a high wattage per channel, there is another factor you must consider: frequency range. Human hearing covers a range of 20 to 20,000 Hz. A receiver that delivers a high wattage per channel, and covers this frequency range is one well worth investing in. Others, may have a high "watts per channel" rate, but have a small frequency range, perhaps something like 40 to 15,000, which will work well, but not as clearly as a receiver that covers the entire human hearing frequency range.

How much wattage you need depends on several factors, including the size of your room, and how loud and how clearly you’d like to listen to your audio. 60-80 watts for the front speakers in a home audio system is typically the average. If you have a larger room or hunger for more clarity in sound, go for 100 watts or so. Medium to higher-priced receivers deliver equal power to all five channels in surround mode. Lesser-priced models may deliver varying amounts of power to different channels depending on whether they are main or surround speakers.

Stereo means 2 channels. When sound is recorded, it is mixed down to 2 channels. When played in stereo through 2 speakers, you hear the sound from left and right channel speakers. Depending on the quality of the recording, music has more of a "live" presence in your room.

Surround Sound is synonymous with Home-Theater. When you go to the movies, if you hang out and watch the credits, you may notice that the movie was recorded in Dolby Surround or THX. Most receivers and amplifiers that we carry have built-in surround sound decoders, mostly manufactured for Dolby surround systems.

Other forms of surround sound have names which change from manufacturer to manufacturer. Virtual Surround, Quasi Surround (Q-Surround) or Spatializer Surround are the most popular. They are not-quite surround sound. They allow a simulated surround effect for those systems that only use 2 speakers. 2-channel stereo sound is processed in a certain way to create a wider audio field. When played, it seems more encompassing than stereo, but not as authentic as Dolby ProLogic or Dolby Digital modes, which use 5 or more channels and speakers.

Dolby ProLogic is a very popular sound system that was introduced in consumer receivers in 1987. Dolby ProLogic divides sound channels in a similar way to movie theaters. Using 5 channels, it requires 5 speakers. The front left and right speakers may be similar to those used in stereo and they mimic the sound heard to the left or right of the theater screen. A front center-channel speaker delivers the sound that would normally come from behind the screen. Two rear left and right channel speakers deliver the sound that may be coming from the rear or rear sides of the theater. Dolby ProLogic was originally developed for videocassette tape encoding and is an analog recording system.

Dolby Digital Surround (sometimes referred as AC3) was developed for the higher performance sound delivered by video CD or DVD media. It was introduced in consumer amplifiers and receivers in 1992 and became more prevalent in 1997. It works with 5.1 channels and sometimes it may be referred as 6 channels. 5 Channels deal with the primary surround environment. Using 5 channels, it requires 5 speakers. The front left and right speakers may be similar to those used in stereo and they mimic the sound heard to the left or right of the theater screen. A front center-channel speaker delivers the sound that would normally come from behind the screen. Two rear left and right channel speakers deliver the sound that may be coming from the rear or rear sides of the theater. It also has a port for a subwoofer, a speaker that delivers extremely low frequencies, which can reproduce special effect sounds in your room with theater-like authenticity. Dolby Digital is often accompanied by DTS sound. "dt's" is a surround sound compression system especially suited for CD and DVD video recordings.

Dolby Digital is often accompanied by DTS digital sound. Most often listed in lower-case letters, ‘dt's’ is a surround sound compression system especially suited for CD and DVD video recordings. Introduced around 1997, DTS offers additional dynamic range and greater fidelity to its source through the 5.1 digital audio duplication process and is used among many major DVD and CD recording studios around the globe.

These are surround modes that are often found in stereo systems and are not quite home-theater. Among the names used, Virtual Surround, Quasi Surround (Q-Surround) or Spatializer Surround are the most popular. They are not-quite surround sound. They allow a simulated surround effect for those systems that only use 2 speakers. 2-Channel stereo sound is processed in a certain way to create a wider audio field. When played, it seems more encompassing than stereo but not as authentic as Dolby ProLogic or Dolby Digital modes, which use 5 or more channels and speakers.

THX is another surround sound system that is less common than Dolby Digital Surround Sound but very similar. The most obvious difference is the manufacturer - it isn’t Dolby. THX was developed by LucasFilm and optimizes the sound used by their films. Only a few receivers and amplifiers have decoding for THX. Dolby Digital, however, can read and reproduce most of the THX coding.

When receivers work, there is engineering in action. What does that mean? Well, it means that when any device is operating, there tends to be a little noise, however insignificant, generated. The harmonic distortion rate is a measurement of the distortion caused when the circuit in the receiver is working. You want to make sure you buy a receiver with the least amount of THD. Most receivers have a THD of less than 1%.