Ed's AV Handbook.com
Home Theater & High Fidelity Stereo Audio
Batting practice for the audio/video pro and a primer for the novice
Index by chapter subject
Ed's AV Blog & NEWS
Chap 2 AV Physics
Chap 3 Sound
Chap 4 Video
Chap 5 AV System Sequence
Chap 6 The Room, Speaker, & TV
Chap 7 Acoustical Strategy
Chap 8 Home Theater by Design
Chap 9 Sales Training
Chap 10 Business & Marketing
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Too many of our AV brethren do not genuinely understand fundamental audio and video terms. I have confounded many for decades with this simple question, "What is stereo?" The answers I receive continue to drive me crazy.
What is stereo?
In an attempt to insure what's left of my sanity, please review the following terms. We may meet on the street someday.
High Fidelity audio refers to the accurate reproduction of recorded sound. It adheres to standards that are typically expressed in terms such as frequency response, signal to noise ratio, and some percentage of distortion. But high fidelity can be defined by two simple questions. Does the reproduced sound of a piano sound as a genuine piano? Does the audio system faithfully reproduce the artist intent?
Monophonic audio is a single channel of reproduced sound that creates a flat two-dimensional sound field. In the 1950's a high fidelity single speaker monophonic audio system was often referred to as a HiFi system.
Stereo audio reproduces two separate audio channels via two speakers placed in an equilateral triangle with a listener to create a three dimensional illusion. This arrangement creates illusions/images of musicians on a stage of height, width, and depth: a drummer centered rear, bass player front right, sax player front left. If it meets high fidelity standards it is referred to as a high fidelity stereo audio system.
Multi-channel surround sound introduces additional channels and speakers onto the stereo arrangement. It is a circular arrangement of four, five, six, seven, or more speakers that surround the listener in an extended illusion of staged music or in an envelope of movie sound effects. Surround sound is offered in many formats which are discussed later in this chapter.
NTSC analog television has been retired.
'National Television Standards Committee' broadcast was the original U.S. television standard. Some joked that NTSC was an acronym for 'never twice the same color'. An expanded explanation of NTSC is outlined in chapter four.
ATSC (Advanced Television Systems Committee) is the U.S. digital broadcast standard of High Definition television (HDTV), Enhanced Definition television (EDTV), and Standard Definition television (SDTV). A new ATSC 3.0 standard will soon add UltraHDTV. Chapter Four covers ATSC in detail.
HDTV - Television is primarily defined by the number of lines and pixels per line that make up a video frame. HDTV is offered in two versions: 1080 lines by 1920 pixels per line, and 720 by 1280. HDTV also expands the color gamut well beyond NTSC TV. Chapter 4 covers HDTV in detail.
UltraHDTV increases resolution and expands the color gamut beyond HDTV.
UHD TV resolution equals 2160 lines by 3840 pixels per line. UltraHD or UHD is often reffered to as 4K TV. As explained in chapter four page 6, UltraHD is not 4K.
I guess this is to be expected in a world where too many in our business do not understand what stereo audio is.
|Ed's AV Handbook.com
Batting Practice for the AV Pro and a Primer for the Novice.
Copyright 2007 Txu1-598-288 Revised 2017