Thread: Home Theatre Blues - Part 5: Connections for getting the maximum out of your AV

In these days of HD, most initiated will know the various resolutions. The video world is defined into four segments:

• Standard Definition (SD): This is the de-facto standard of the yesteryears and is still prevalent even today. In technical terms it means a resolution of upto 480i (in USA and other NTSC regions) and 576i (in Europe, and other PAL/SECAM countries). The "i" stands for interlaced) signal.
• Extended Definition (ED): In the same context as above, progressive scan) made its debut some years ago to get rid of the artifacts associated with interlaced scan. I shall not go into the details. But ED in technical terms stands for 480p or 576p.
• High Definition (HD): HD evolved a few years ago to match the XGA resolution on PCs. HD is typically classified as 720i or 720p (1366x768 pixels).
• True or Full High Definition (FHD): HD quickly gave way to FHD, Full HD is exemplified by a resolution of 1920x1080 and can be 1080i or 1080p.

This article is mainly on how to get the maximum out of your components - Blu-Ray Player, DVD Player, TV, AVR, DTH, etc.

But before that you must understand your source:

• DTH/Cable: Unless you are subscribing to Sun DTH HD (and that too a few channels), all transmission in India is in SD. Whether your STB is MPEG4 or MPEG2, has component out or just composite, you are going to get SD quality only.
  
  p/s: When this article was written Sun DTH HD was the only HD-TV source. Lot of water has flown through the Ganges by this time.
• DVD Player: The DVD (disc) by itself is SD quality. But your player may be progressive - in this case the output will be ED. Or the player may be able to upscale to full HD (1080p).
• Blu-ray player: The typical BD has the main movie in full HD while the bonus content may be in SD or HD. BDP's can play DVDs also and upscale them to 1080p.
• AVR: The AVR may have HDMI connections and capability to upscale analogue or digital video to full HD.

Regardless of the source, the output medium must also be considered. Typically this is the TV in most homes. But some people may own a projector also. This is what your TV is capable of:

• Old CRT TV: Such a TV can display SD at 480i or 576i only. Certain 100/120 Hz CRT TVs overcame the problem of interlaced transmission (flickering) by having double scan frequency thus emulating progressive scan. But that's about it.
• HD-ready LCD/Plasma: These TVs are capable of native display of 720p signals. They can also receive upscaled 1080i signals and thus are called HD ready.
• Full HD LCD/Plasma: These TVs are capable of native display of 1080p signals.

Needless to say, that all high resolution TVs can scale down to display signals of lower quality, i.e., they are downward compatible.

Considering all of the above, how does one get the maximum out of one's system? To understand this, let me explain the different types of AV connectors:

• RF connector: This connector is coaxial in shape and is designed to work on radio frequency; hence the name. It can display SD quality picture.
  
  The typical RF connector is shown below:
  
• Composite connector: These are RCA connectors and there are three wires/plugs in the connection. Yellow RCA is for analogue video, while white RCA is for left channel audio and red RCA is for right channel audio.
  
  Picture below shows the composite cable connectors:
  
• S-Video connector: S-Video connector is pure analogue video connector only. It was invented to get a better colour resolution than composite video. You must connect audio connector separately with the S-Video connector because this connection does not carry audio.
  
  An S-Video cable with connector is shown below:
  
• Component connector: The component connector also uses RCA plugs and cable looks similar to the composite AV cable. But that is where the similarity ends. The component cable is pure (analogue) video cable only. It requires separate audio connector. The component cable carries split video in three connectors.
  
  A component video cable is shown below:
  
• HDMI: HDMI is current standard for high definition video and carries digital video as well as audio. This is the only connector that adheres to a digital connection.
  
  The HDMI connector is shown below:
  

In this article, I have deliberately left out SCART and DVI. SCART is mainly used in Europe and is another form of analogue AV connection. DVI is mainly used in computers and carries digital video (no audio).

Now coming back to the topic, after you have analyzed the capabilities of your devices, do the following:

• You should also use the connections in the following priority:
  1. HDMI
  2. Component Video + RCA Stereo Audio
  3. S-Video + RCA Stereo Audio
  4. Composite or RF
• Use HDMI whenever possible. But note that if your TV is HD-Ready (and not full HD), it may not be able to display at 1080p setting. In this case reduce the output setting at the source to 1080i or 720p. First try 1080i; if it does not work then reduce to 720p.
• If you are having a CRT TV, then you may have no option other than using either RF or Composite Video connector. Certain new models of CRT TVs have component also.
• As mentioned in my previous articles, when HDMI @ 1080p is selected at the source output, the analogue video is not output at any of the connectors (component or composite or elsewhere). This is very important to remember.

Notes:
1. HDMI is capable of 480i, 480p, 720i, 720p, 1080i, and 1080p.
2. Component is capable of 480i, 480p, 720i, 720p, and 1080i.
3. RF, Composite and S-Video is capable of 480i and 480p only.

Sources (for images only): Wikipedia and others

Can you please tell a bit more about video upscaling. What is it exactly? Will a DVD upscaled to 1080p look better than without any upscale at all ? Will the playback of an upscaled DVD movie be affected if we use composite Vs HDMI ?

Originally Posted by rajan1311

Can you please tell a bit more about video upscaling. What is it exactly? Will a DVD upscaled to 1080p look better than without any upscale at all ? Will the playback of an upscaled DVD movie be affected if we use composite Vs HDMI ?

Very good and relevant questions.

Upscaling is, as the dictionary will suggest, converting something of lower value to a higher value. In terms of video, the picture of lower resolution is converted to a higher resolution. Consider that a picture of 640x360 pixels is being upconverted to 1920x1080. This means that additional pixels have to be added where missing. This is done by an intelligent circuit. It looks at the source pixels (colour, luminiscence, etc.) and tries to produce/replicate the matching pixels for the enhanced resolution. Upscaling in video is usually to 1080p but one can select any lower resolution also.

You can equate upscaling of video to digital zoom of a camera. Though this is a very crude example - video upscaling is not as bad as digital zoom.

Depending upon the upscaling technology and circuit used, the picture may look better but sometimes look worse. So to answer your second question, an upscaled DVD will usually (>90% of times) look better but in certain cases may look worse.

Finally, component vs. HDMI. Upscaling is a digital process. So component out will not be able to display upscaled content as component video is analogue. To view upscaled content, you must therefore use the HDMI cable. Also remember that analogue video can be upscaled but output via HDMI only.

It should be noted that under no circumstances will an upscaling/upconverting provide "high-definition content".

Hope this answers your queries.

thanks a ton. This cleared all doubts

Part 6(a) (Home Theatre Blues - Part 6 (a): Choosing the TV) is now online.