1.0 Monaural Sound Systems
To understand the difference between 5.1, 6.1, and 7.1 it is helpful to know some of the history of sound reproduction equipment. In the beginning, all sound equipment was monaural(1.0). This means that all sounds came through a single channel and out of only one speaker. Unfortunately the sound quality was not very good.
2.0 Channel Stereo Systems
The first significant improvement to revolutionize the sound industry was the invention of stereo where the sound is transmitted using two independent channels. For any given number of audio channels, there is an optimal physical setup for the speakers that produces the best effects. (This is shown in the blue boxes embedded on this page.)
The was a totally outstanding improvement. For the first time ever, you could experience sounds traveling from one side of you to the other! A stereo system (2.0) consists of two-channels of sound produced by two independent speakers — left and right. This was the first time that listener felt a sense of realism for what they were listening to. People listening to concert music could close their eyes and imagine they were sitting in the middle of the concert hall. Any equipment that did not have a set of speakers rapidly became expendable.
5.1 Channel Systems
5.1 Channel A/V receivers have five full frequency range channels. These channels are left/right, center and left/right surround channels. For best results, we recommend that you follow our speaker placement guidelines when setting up your home theater.
An additional subwoofer channel (the .1 or LFE channel, Low Frequency Effects) adds very low frequency sounds for music sources and special effects on movies from DVDs.
6.1 Channel Home Theater Systems
6.1 channel systems have an additional rear-center channel speaker for a total of three front and three rear speakers. 
6.1 channel sound provides more precise positioning of sound effects and creates a more enveloping soundfield.
7.1 Channel Home Theater Systems
7.1 channel receivers have three front channels, two surround channels, two surround-back channels, and a subwoofer channel. The recommended speaker set up or a 7.1 channel sound system.
If you are a home theater newbie, buying a home theater receiver may be a high anxiety undertaking for you. Hopefully, we can fix that.
In most home theater applications, the receiver is responsible for audio and video switching, surround sound decoding, signal processing, and amplifying in addition to being an AM/FM radio tuner. Other terms used interchangeably with home theater receiver include the following: audio/video receiver, video/audio receiver, surround receiver, and receiver to name a few.
Choosing the cheapest receiver is not always the best way to go. A far better approach is to find a unit that will meet your present and anticipated needs, and worry about the price later. See how much the best receiver to match your needs actually costs. You will most likely be quite surprised when you see how affordable it is.
Digital ToP-ART (Total Purity Audio Reproduction Technology) is the name Yamaha has given to a design philosophy whose goal is to maximize digital quality while minimizing analog circuitry. The culmination of Yamaha’s long experience in digital engineering and design, it brings together several key elements to create the best-sounding, A/V components available on the market.
Yamaha’s YPAO system uses a small microphone and sophisticated equalization to automatically set the best sound for any room, no matter where the speakers are. First it checks the speaker connections and phase of each speaker. Then it sends out tones which are captured by the microphone to analyze the room acoustics and sets a variety of parameters, such as the speaker size, the distance of the speakers and even the sound pressure level, etc. Until it achieves the best sound conditions for your room and you don’t have to do anything!
Four SCENE buttons make operating the receiver easier than ever. They are initially set to default settings for DVD Viewing, Disc Listening, TV Viewing and Radio Listening. Pressing a SCENE button automatically launches a number of operations that initiate play of the source controlled by that button. Other SCENE settings are also available, such as iPod Listening, XM Listening, TV Sports Viewing and Action Game Playing. Browsing and selecting the settings is quickly accomplished by rotating the Input knob and watching the on-screen display. The settings can be selected for one-time use, or they can replace the original default settings. The SCENE names can be changed also.
Yamaha employs sophisticated digital signal processing with exclusive algorithms to enable playback that improves the performance of compressed music formats, including MP3 and WMA. With the Compressed Music Enhancer, highs and especially lows are richer and smoother, bringing music back to life to be as close to the original as possible.
SILENT CINEMA makes it possible to hear large-scale surround sound through ordinary headphones! This is a variation of CINEMA DSP technology that Yamaha developed to let you listen in private to movies and other multi-channel sources for hours without listening fatigue. Virtual CINEMA DSP lets you enjoy the effects of CINEMA DSP surround sound without using surround speakers (handy for use in custom installations where some rooms don’t have surround speakers). It can be used with the front / center / presence speakers or even with just the two front left and right speakers.
Conventional multichannel audio reproduction systems base their sound on Dolby Digital and DTS decoding, using matrix and steering technologies to create surround sound effects. Yamaha CINEMA DSP is much more advanced, actually creating richly realized independent sound fields that envelop you in an unmatched surround sound experience. With dialogue, music and effects from ideally located in these separate sound fields, you will hear sound with accurate placement, smooth movement, exceptional clarity and richness, and startlingly realistic presence. It will seem as if the walls of your room have disappeared and you are in the middle of your own immense theater! The decoding circuitry performs Dolby Pro Logic IIx, Dolby Digital, Dolby Digital EX, DTS Digital Surround, DTS-ES (DTS-ES Matrix 6.1 and DTS-ES Discrete 6.1), DTS Neo:6 and DTS 96/24 decoding with extreme accuracy, as well as all digital sound field processing.
8 additional input jacks for discrete multi-channel input. Front (Left, Center, Right), Rear (Surround Left & Right, Surround Back Left & Right) and Subwoofer
A Sirius-Ready audio system lets you access your favorite SIRIUS Satellite Radio entertainment, including 100% commercial-free music, plus sports, uncensored talk, comedy, exclusive entertainment, world-class news and more, directly through your audio system with the use of an optional SIRIUS ConnectT Home Tuner kit. This product has a simple connector that allows you to plug the SIRIUS ConnectT kit and use the controls of this system to access all the content you want. Subscription and SIRIUS ConnectT Home Tuner (SC-H1) are required and sold separately.