What is Dolby, and why is it so important to Home Cinema enthusiasts?

Dolbydolby, tv sound, sound quality first came to prominence as a noise reduction process, invented by Thomas Dolby in the 1960s. Before his noise reduction process was developed static and hiss on magnetic tapes and optical film would spoil the sound of a movie. Various ways were tried to get around it, such as reducing treble but using this method could only go so far before the dialogue began to be distorted or muffled.

As tape was rapidly superseding optical sound reproduction (a process where the sound is recorded as a visible signal on the edge of the film and converted back into sound when the film is run through a projector which is fitted with the right audio capability) the Dolby Noise Reduction (NR) was applied to improving the sound on tape by electronically suppressing the noise which is inherent in magnetic tape recordings.

To Dolby, Both Clarity And Quality Of Sound Was All Important

If you’re old enough to remember stacking hifi systems with a Dolby button you’ll know that the process could also be applied after production as well. Put in a tape, press play and turn the Dolby on and you’d see an immediate improvement to the sound you heard. And if you remember that, you’ll remember the Loudness button too, the inexplicable switch that just made everything a little bit louder. The actual point of that was so that when you were listening at low volume you could turn it on and not lose any or the richness of the sound which usually goes when you aren’t able to turn the sound up loud.

The first film to be recorded with Dolby Sound pre-mixers and master tapes was A Clockwork Orange. If you’ve seen it you’ll know that not only is the clarity of the dialogue important, Alex is a committed audiophile with a love of classical music and it was important to get the sound over to the audience as cleanly as possible. While the sound was recorded with Dolby, when the print was released it still had to have an optical soundtrack as that was how all the cinema projectors of the time were set up.

The first film to be released with a Dolby encoded optical soundtrack was Callan in 1974. The movie was a spin-off from the Edward Woodward TV series of the same name which itself borrowed heavily from the Harry Palmer movies, starting with The Ipcress File almost a decade before.

The next big step for Dolby Sound was the introduction of Dolby Stereo, first seen on screen in 1975’s Lisztomania. Naturally a film based on the life and work of the composer Franz Liszt required the best quality sound, and the introduction of stereo meant effectively having 2 optical soundtracks on the same film. The stereo used on Lisztomania used three channels: left, centre, and right (LCR). The next leap came with A Star Is Born in 1976 when the sound was recoded on a left, centre, right, surround (LCRS) soundtrack.

Now that digital sound recording is ubiquitous Dolby NR is redundant. There is no inherent hiss in the technology, and any hums produced by recording equipment being too near power cables can simply be switched off in the edit. However, that doesn’t mean that there is no need for Dolby’s innovations.

Look again at LCRS. You may only have two ears, but there are at least four channels involved. What Dolby discovered is that immersive, convincing sound doesn’t just depend on crystal clear sound coming from the left and right, it needs to come at you from all around. A film which took great advantage of surround sound was Twelve Monkeys. In several scenes voices and noises would come at the audience from every side of the cinema, an effect which was lost to anyone watching the movie on TV until the introduction of home surround sound and the digital soundtrack which could handle creating sound for all those channels. (Your home entertainment centre may have boasted surround sound, but if the original source was a VHS cassette, there was no way of hearing what Gilliam, who directed the movie, wanted you to hear.)

Now that we have DVD, BluRay and HD streaming whenever we want it our sound systems have to be capable of processing many channels. We no longer hear of LCR or LCRS because instead we need to talk about 3.1, 5.1, 7.2, and even 9.2.

When you’re looking at those numbers what you’re seeing is, in the first digit, the number of primary speakers (3 represents left, centre right, for example) while the second digit represents the subwoofers, the speakers which make a sound so low and powerful you can feel it as much as you can hear it. The higher the number of speakers you have, the greater the sensation of having sound all around you. And obviously when you’re setting up your TV and adding all those speakers, you need to make sure you place them correctly. There was nothing to go wrong when we were all listening in mono, and your TV will have built in speakers which play the correct channel, but if you’ve set up your 9.2 and they’re in the wrong position the sound you hear is going to be unsettling at the least, confusing and aggravating at worst. Which is why it’s important to get it set up correctly to begin with.

If you’re going to invest in the best home entertainment systems it’s worth getting them professionally installed. Briant Communications offer a home cinema installation service which handing your flat screen TV on the wall, installing sound bars, and amplifiers, recessed wall and ceiling speakers, audio visual systems, or wireless music systems, all carefully positioned to ensure that you see the best picture and hear the most natural sound and the clearest music.

Call Briant Communications on 01273 465377 or email enquiries@briantcomms.com

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