Title:

Understanding Surround Sound Systems

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Summary: Surround sound is a term that typically gets utilised in discussions of property theater technologies. Mitchell Medford explains specifically what sets surround sound systems apart from standard ones and what it indicates for you.

Key phrases: surround sound, television, stereo, dts, residence theater, plasma, lcd, hdtv

Post Body: Surround sound is the idea of expanding the spatial imaging of audio playback from 1 dimension (mono/Left-Appropriate) to two or 3 dimensions. It is typically utilised for a far more realistic audio environment, actively implemented in cinema sound systems, technical theatre, house entertainment, video arcades, pc gaming, and a growing number of other applications. Numerous well-liked surround sound formats have evolved over the years. They consist of ambisonics, quadraphonic, Dolby five.1 Surround sound, DTS, and MP3 Surround.

Surround sound can be produced utilizing Many techniques. The simplest to understand uses A lot of speakers around the listener to play audio coming from various directions. An additional technique entails processing the audio making use of psychoacoustic sound localization strategies to simulate a 3D sound field employing headphones. The third method, wave field synthesis, uses a extremely big number of speakers to create the "audio hologram" of the original audio in the entire room (as of 2004 the only commercial implementation of this is Iosono). Surround sound is not limited to placement of speakers along a flat (2-dimensional) plane. Vertically-situated audio sources can be regarded as.

Dolby Digital (DD) uses the AC-three file format, which any Dolby Digital Decoder can decode to produce five.1 audio. Dolby Digital is the technical name for Dolby's multi-channel digital sound coding technique, far more generally referred to as Dolby five.1. A six-channel sound coding process originally developed by Dolby for theaters, AC-three was subsequently adapted for property use and is now steadily becoming the most typical sound format for DVD.

Six discrete audio channels:

•three for speakers at the front - left (L), center (C), and Correct (R) •2 for surround speakers at the side or rear - surround left (SL) and surround Appropriate (SR) •1 low-frequency effects (LFE) channel carries supporting deep bass sound effects, ranging from 10 Hz to 120 Hz, which can for example be employed by a subwoofer. (This is the '.1' in 'five.1'.)

DTS is an encode/decode process that delivers five.1 channels of "master high quality" audio on CD, CD-R, and DVD. Every DTS encoded disc represents a sonic "clone" of the original film soundtrack.

The distinction between Dolby Digital (AC-three) and DTS is:

•DTS offers a deeper and tighter low frequency presence •DTS permits the sound to breath - transparency •AC-three leaves the impression that some thing is missing from the mix •At lower bit-rate AC-three starts to sound like MP3's encoded at a low-high quality 96kbps (artifacts)

DTS is much more 3 dimensional. The sound truly moved forward from the individual speakers to sound much more full. This fullness was most apparent with the music. Instead of just coming from the speakers, the DTS filled the front soundstage not only side to side, but with far more depth as properly. Bass reproduction was also a lot more defined in the DTS version, leaving the DD edition sounding muddy.

Dolby Digital incorporates dialog normalization, which alters the decoded level of the soundtrack. The typical setting reduces level by 4 dB; other reduction levels are achievable. In most decoders, this leads to a reduction in signal-to-noise and dynamic range.

Dolby Digital also gives a "stereo down mixing" feature as a substitute for a dedicated stereo mix. Nonetheless, A lot of production engineers have admitted that they usually have to modify the original five.1 mixes in order to attain acceptable stereo down mixes. As a result, the five.1 mix on Several Dolby Digital DVDs may possibly differ from the original master.

five.1 Surround Sound Headphones:

Although the conventional technique of surround sound described above uses A lot of speakers to produce the whole sound field, the surround sound mix is limited to a two-channel stereo mix when making use of headphones. That is why recent developments in surround sound technologies contain five.1 surround sound headphones, to enable you to have the identical sound top quality and surround sound expertise without having waking the neighbors or disturbing roommates.