This blog is moving!

Lately, I ran to a little bit of problem with Adsense. The account I had with them, the result of which was the ads you might have seen every now and then on this blog, was suspended and my efforts to reinstate the account proved to be futile. This along with the fact that I am trying to collect my results and gather my thesis results in my long absent from this blog.

Therefore I decided to move this blog over to wordpress and as it happens this move has collided with my physical move to a new apartment. For the time being, please continue reading my posts at this address. If you have subscribed to my feedburner RSS you will be fine, as I have already redirected that to my new address. But if you are following through the traditional RSS or atom feed address then I am afraid you will have to change that to this. This will be my last post of this blog on blogspot.

Surround Sound Specifications

The description of surround sound specifications brought here is categorized using the number of discrete channels encoded in the original signal and the number of channels available for playback. Each channel may refer to a group of speakers. The graphics shown here denotes the number of channels, not the number of speakers.

3.0 Channel Surround (Dolby Surround)
Three audio channels are produced from a specially encoded two-channel source:

• Two channels for speakers at the front-left (L) and right (R).
• One channel for surround speaker or speakers at the rear-surround (S).
  

Placement: Three identical speakers placed equidistant around a central listening position. If two rear speakers are used they should also be placed above ear height, slightly behind the listening position, and should be of bi-polar construction.

4.0 Channel Surround (Quadraphonic)
Four audio channels are produced either from a specially encoded two-channel source or a four-channel source:

• Two channels for speakers at the front-left (L) and right (R).
  
• Two channels for surround speakers at the rear-surround left (LS) and surround right (RS). Some newer receivers support the LFE channel.
  

Placement: Quadraphonics is a system designed for music only. All speakers should be at an ±45˚. All speakers should be above ear height.

5.1 Channel Surround (3-2 Stereo) (Dolby Pro Logic II)
Five audio channels are produced either from a specially encoded two-channel or a stereo source:

• Two channels for speakers at the front-left (L) and right (R).
• One channel for speaker at the centre-centre (C).
• Two channels for surround speakers at the rear-surround left (LS) and surround right (RS).
• One low-frequency effects channel (LFE).
  

Placement: 5.1 speaker layouts should conform to the ITU-R BS.775 standard, despite the myth that music and video content require different placements. The ITU standard states that the left and right speakers are located at ±30˚, while the rear speakers should be positioned approximately ±110˚. There is speculation that rear loudspeakers at ±150˚ provide "more exciting surround effects".

(to be continued)

Surround Sound Systems

Surround sound systems use multichannel audio to enrich the sound reproduction quality of an audio source using additional audio channels reproduced by additional discrete speakers. the three-dimensional space of human hearing can be achieved using audio channels above and below the listener. Surround sound technology is used in cinema theatres, home theatre systems, video game consoles, personal computers, and so on.

Low Frequency Effects (LFE) Channel
The Frequency Effects channel (LFE) is originally developed to carry extremely low (sub-bass) sound effects such as thunder or explosions on a separate channel. This allows the theatres to control the volume of sound effects to suit the size of their sound system and the acoustic environment of their cinema. However, home system may not have a separate subwoofer that can handle such effects. Therefore, modern surround systems often incorporate a bass management system that allows bass on any channel to be fed only to speakers than can handle low-frequency signals.

Home Cinema

Home Cinema (a.k.a. Home Theatre) is basically an entertainment system that reproduces movie-theatre quality video and audio at homes. The first home cinema systems were 8mm film projector equipment which was replaced by laser discs. In mid 1990's, a typical home cinema would have been a laser disc or VHS videocassette player fed to a large rear-projection television. In late 1990's, DVD players with Dolby Digital (5.1 channel audio) were introduced along with high definition televisions. Nowadays the term home cinema includes a wide range of systems. The display might be a 60" HDTV and for audio, several thousand watts of power fed into a 12" (or more) subwoofer with five or seven surround sound speakers. The price on these equipments can go as high as $100,000.

Basically a home cinema is composed of the following components:

1. Input Device: Any audio/video source that can include high quality formats such as blu-ray. Others include VHS player or video game systems. Some of the newer models include a home theatre PC that acts as a library for video and music content.
2. Processing Device: Input devices must be processed for complex surround sound output.
3. Audio Output: Normally systems come with two speakers but can have up to 10 speakers and an additional subwoofer.
4. Video Output: A large High Definition display that can be LCD, plasma, video projector, rear-projection television or a traditional CRT television.
5. Atmosphere: High-end home theatres have sound insulation to prevent noise from escaping the room and a specialized wall treatment to balance the sound within the room.
   

Feed Burner

It has come to my attention that most of my feed subscribers have subscribed to old feeds (such as RSS and Atom) generated by BlogSpot itself. Promising as the large number of subscribers are, I should draw your attention to the new feed which is burned using FeedBurner at this address. This new feed enjoys a whole set of new features including but not limited to amazing compatibility to different feed readers, possibility of sending the post to your favourite sharing website, and of course more beautiful ads are featured!


So please change the old feed address to this. And happy St. Patrick day to everyone!

Television Buying Guide 8

Things to Consider

• Every floor model television is set its brightness to maximum. Try and ask the salesperson to reduce the brightness of the television you are comparing.
• Display floors are well-lit. Few living rooms are lit that much. See if you can ask them to reduce the light shedding on the picture.
  
• Blu-ray. If you have a disc that you are familiar with, see if you can use it instead of the TV signal that is normally shown. Blu-ray provides the best picture a television can display, so it makes for the best reference from which to judge. And if you are used to the look of a particular DVD, use it instead.
• Televisions come with many picture presets such as movie, sports, etc. Try all of them to see which is best.
  
• It is strongly recommended to protect your television with some sort of surge protection. Do not believe the hype that a better protector will somehow improve video quality, but do choose a model with coaxial inputs and outputs for your cable or antenna.

This concludes the series on television buying guide.

Television Buying Guide 7

Television Sound
Almost every new television has MTS (Multichannel Television Sound) stereo speakers, which is much better than a single mono speaker. MTS is a standard that allows the encoding of 3 channels of audio within a standard NTSC (analog) video signal to a television. A television that is able to receive MTS Stereo allows you to watch television with stereo sound. Usually 5 watts per channel or higher provides a decent audio system for a television. Some sets can simulate surround sound to provide semblance of rear speakers.

Of course no television can compete with a dedicated audio system. You can consider a home-theatre audio system for maximum impact.