DVD Players
& Recorders
DVD players
have become
the fastest
selling consumer
product of all
time. When you
look at all of its
wonderful
benefits, it’s
easy to see why.
Every mainstream film is now available on DVD (Digital Versatile Disc), while more and more
idiosyncratic movies are finding their way onto our favourite magic little silver circles.
The main advantage of watching a movie via a DVD player is the enhanced picture quality.
Picture resolution is streets ahead of VHS, and DVD discs don’t suffer from the snarl-ups that dog
videotape. Also, unlike VHS, the picture quality doesn’t degrade so images look as good the
hundredth time you play the disc as they did the first.
Even better is DVD’s audio performance. All new DVD movies are encoded in Dolby Digital 5.1.
Once decoded, either by the DVD player or a suitable home cinema receiver, this delivers soundtracks
through five surround speakers and a subwoofer - the ‘point one’ - creating an amazing cinema in
your own home.
Hi-fi buffs are also very excited about DVD. This is because the new DVD-Audio format boasts
ultra-revealing 24-bit resolution and a stunning 192kHz sampling rate, delivering ‘better-than-CD’ sound.
When paired up with quality amplification and speakers the discs really do sound stunningly good.
Other advantages of DVDs include ease-of-use and the array of added features that normally come on
the disc. As DVDs are a digital format you can instantly access anywhere on the disc using the chapter
system, so there’s no time consuming rewinding or forwarding. In addition nearly every DVD includes
extra features, be it the film’s trailer or in-depth interviews with the stars.
One question that continually crops up with DVD players is: ‘what discs can I play on them?’ This all
stems from the fact that DVD manufacturers and film distributors have carved the world up into a
number of regions, with the United States being Region One, while Europe, including the UK,
is Region Two. Because of this discs bought from high street outlets in the UK will, on the whole,
be Region Two discs, which will only play in Region Two machines.
Fortunately, most DVD players can now be made multi-region and will therefore play DVDs from any region.
It’s worth noting that many new DVD players can normally handle a raft of other discs. These include:
CD; CD-R - a write once audio CD; CD-RW - a rewritable audio CD disc; MP3 encoded discs
- the digital audio compression technology that dramatically reduces the amount of data needed to
reproduce music and has become the standard way of downloading music files from the internet; VCD
(Video Compact Disc) which is essentially a CD that contains MPEG video files, the quality of which is
generally rather poor; SVCD (Super Video Compact Disc) discs, which is a higher quality, upgraded
version of VCD which can also hold surround sound; finally, there is Kodak Picture CD, which is a disc
burnt by the developer containing digital images from the original film.
DVD Recorders
Another set of discs which can be watched on DVD players is those produced by DVD recorders
- and this technology deserves to be looked at in far more detail.
Each of these designs produces stunning recordings - far superior to VCRs - and boast all the
marvellous editing benefits of a digital-based recording format. Say bye-bye to those annoying adverts
in the middle of films!
The big problem with DVD recorders is the lack of an international standard. This means that at
present there are three different types of DVD recorder available on the market - DVD+RW, DVD-RW
and DVD-RAM - as intimidating a line up of acronyms as ever there’s been. These have been
developed by respectively Philips, Pioneer and Panasonic.
Moreover, there are issues regarding compatibility with conventional DVD players. DVD-RAM
recordings won’t play in any other DVD player, as they are predominantly cartridge based, nor will
DVD-RW, and although DVD+RW has greater backwards compatibility, it is still far from universal.
Fortunately, there are solutions to the above problems. By recording onto DVD+R or DVD-R discs
(the write once versions), you will be able to play your copy in nearly every machine around, though
you then lose the ability to use the disc for recording again. Meanwhile, multi-format machines are
being introduced which play at least two of the three recording formats, getting round the entire format
war altogether.
Recent Developments
DVD may offer stunning levels of quality, but it is still improving! As we all know the world of home
cinema electronics rarely stays still for long. For example, more and more DVD players are now making
use of progressive scan technology. This is a new way of drawing the image on a screen and delivers
massively improved images.
Equally exciting are the new video connections that are entering the arena. From the very first DVD
machine the transfer of audio data from player to AV receiver has been digital domain, yet video has
remained the poor relation, using conventional analogue cables.
All that is changing with the advent of DVI and HDMI. In a nutshell both these are two connection
systems capable of carrying high-quality digital video signals (although HDMI also has the potential to
carry audio data).
DVI (Digital Visual Interface) was first mooted in 1998 and uses Transmission Minimised Differential
Signalling (TMDS). This allows the transfer of 24-bit data for RGB signals, broken down into three
TMDS signals, one for each colour. DVI also has the capability of doubling this transfer if additional
data needs sending, say when using a progressive scan signal.
HDMI (High Definition Multimedia Interface) was dreamed up by consumer electronics companies as
an alternative to DVI. You see they needed a much smaller connector, and came up with a few
cunning additions while they were at it. HDMI can transfer 5GB/sec of component quality data (wow!)
and can also carry high quality audio signals.
One final point, both the above connections offer content protection, so the big movie studios have
given them the thumbs up.
Hard Disk Recorders
Another major development is hard disks, which are actually already with us. Quite a few
manufacturers have introduced HDD (Hard Disk Drive) technology into their DVD recorders. Not only
do these ingenious devices play and record onto DVDs, but they can also record straight onto, or play
from, an enormous hard drive eliminating the need for a disc altogether. Another great feature of HDD
+ DVD-RAM machines is ‘Time Slip’ technology, which lets you start watching a programme, while the
machine is still recording the rest of it!
As hi-fi and computer technologies converge the use of hard disk technology is sure to increase, with HDD
devices being used to play back both audio and video data, perhaps from the same machine.
Blu-Ray
Another technological advance has been the development of Blu-ray, or Blu-ray Disc (BD). This is
a next-generation optical disc format developed to enable recording, rewriting and playback of
high-definition video (HDTV) on huge capacity discs that hold up to 27GBs of data (nearly six times
as much as a conventional DVD). There are also plans for even higher capacity discs, which are
expected to hold up to a whopping 50GB of data.
Current optical disc technologies use a red laser to read and write data. The benefit of using a blue
laser is that it has a shorter wavelength, which means that it's possible to focus the laser beam with
even greater precision. This allows data to be packed more tightly on the disc and makes it possible to
fit more data on the same size disc. Such players probably won’t hit the stores until 2006 and despite
the different type of lasers used, Blu-ray Disc machines will be made compatible with current red-laser
technologies and allow playback of CDs and DVDs.
This last point is worth stressing. DVD has been so successful and so deep has its penetration into
the market been, even within its relatively short lifespan, that any new machine designed will always
play DVDs.