NTSC vs ATSC
NTSC (National Television System Committee) is a set of standards developed by the body of the same name for broadcasting analog TV signals that was adopted in great parts of the world. In comparison, ATSC (Advanced Television System Committee) is a newer and better set of standards that govern the digital transmission of TV signals. The change is very much like the jump from VHS to CD in home theater systems.
There are a number of advantages that are being offered by ATSC over NTSC. The most prevalent is the ability to carry HDTV signals. Even if you have an HDTV set, if you are still receiving the TV signal via NTSC, you would still have SDTV resolution and quality as NTSC lacks the ability to carry HDTV. Since HDTV requires a lot more bandwidth compared to SD, we can say that ATSC is better since it accommodates more information even if it still occupies the same 6Mhz bandwidth allocated to NTSC. To make a better comparison, ATSC can carry up to six SD quality video streams whereas NTSC can only carry one. ATSC also follows a wide screen format more popular in movie houses since while NTSC follows the boxy 4:3 ratio which was dictated by the use of CRT technology.
Another key advantage of ATSC is the ability to carry 5.1 surround sound. NTSC is only able to carry 2 channels of sound leading to stereo quality sound. With ATSC, as long as you have the right equipment and speakers to decode and playback 5.1 surround sound, you can have a much better viewing experience, especially with movies.
As TV begins to slowly move to the digital age, NTSC is also gradually being replaced by ATSC in parts of the world. Although most areas still use NTSC, others have begun putting up ATSC transmitters and older NTSC towers are being turned off and decommissioned. If the advantages of ATSC are not enough to sway a user to getting a newer digital TV, the inevitable disappearance of all NTSC signals should be motivation enough.
Summary:
1. NTSC is a set of standards for analog TV transmission while ATSC is a set of standards for digital TV transmission
2. ATSC allows HDTV quality while NTSC does not
3. ATSC uses the wide screen format while NTSC follows the 4:3 ratio
4. ATSC requires much lesser bandwidth compared to NTSC
5. ATSC is able to transmit 5.1 surround sound while NTSC is not
6. ATSC is gradually replacing NTSC