HOME CINEMA FOR BEGINNERS...
Home cinema is all about recreating the
sensations of watching a movie at the cinema, in your own living room. There’s two
ways of going about it; the first involves chucking a load of half-eaten ice-creams
on the carpet, eating week-old hot-dogs and asking the neighbours in to have an
argument whilst you try to watch a movie on video. It’s cheap and quite
realistic, but not particularly satisfying. The alternative is to invest in a
few extra pieces of equipment, to go with your TV, VCR and hi-fi, that will
turn your sofa into the best seat in the house.
It needn’t be expensive, providing you’ve
already got a fairly recent TV and video recorder, a basic set-up could cost
you less than couple of hundred pounds, but be warned, the sky’s the limit. If
you get bitten by the bug you could easily spend £2000 without blinking, and
that’s before you add on the cost of an extension to your house, and the
So where do you start? The technology can
appear bewildering at first, but don’t let that put you off, the phrases you’re
going to see over and again are Dolby Surround and Pro Logic, all you need to know
at this stage is that they refer to sophisticated multi-channel surround sound
systems that were originally developed for use in movie theatres, but are now available
in an affordable domestic form; we’ll go into the why’s and wherefores later
on. You might also be wondering how it is possible for a standard British living room to sound
anything like a cinema auditorium, believe it or not it can be done, and it doesn’t
involve knocking down walls, surgical implants or mind-altering chemical
substances! But do you really need all this extra technology in your life?
Well, that’s up to you, but it might help you to know that every time you watch
a movie on TV or video you could be missing out on some pretty dynamic effects;
and if you’ve ever wondered what it’s like to have big Arnie blowing up petrol
tankers on the rug in front of you, or the Batmobile screaming out from behind
your settee, then this is your chance to find out!
So what exactly do you need? There’s several different routes into home
cinema, from upgrading or integrating your present video and audio equipment,
to starting from scratch. There’s no right or wrong method, it all depends on
what you’ve got now, how far you want to go, and how much you’re prepared to
spend. Upgrading suits most people to begin with, though there are pitfalls to
be aware of. Obviously you need to have a stereo hi-fi video recorder, and some
sort of hi-fi system in the first place. There’s going to have to be changes; the
hi-fi will have to be positioned close to the TV and VCR, and the speakers must
be placed a foot or two either side of the TV screen, and that may not always
be convenient, especially if the system is still going to earn it’s keep as a
hi-fi, or if other members of the family want to use it, when you’re watching
We spoke a moment ago about the need for a
stereo VCR, that’s not strictly true, there’s other source components you could
use, like a stereo satellite tuner, or maybe a laser disc player, but a stereo
VCR, preferably one made within the past five years with a NICAM decoder, is
going to give you access to the widest range of material.
So, assuming you already have the core
components -- a decent size TV, stereo VCR and hi-fi system, what else do you
The minimum requirement for a home cinema
system is a Dolby Surround decoder or processor, and some extra speakers. In
the early days -- three or four years ago -- there were two types, known as
‘active’ or ‘passive’. Passive decoders, which can only resolve one extra
channel (see The Dolby Story), have all but disappeared, nowadays most decoders
rely on active or ‘Pro Logic’ technology to extract four sound channel. The
decoder box connects between the output of the AV source component -- VCR, satellite tuner etc. -- and the auxiliary
input of the hi-fi amplifier. Amplifiers built into the decoder drive a pair of
small speakers placed behind the viewing position, and (in the case of a Pro
Logic decoder) one in front of the TV screen. The main stereo channels are
heard through the hi-fi’s own speakers. Stand-alone Dolby processors are the
cheapest, and oddly enough, also the most expensive home cinema components,
with prices ranging from under £200 to almost £1800.
Purpose designed AV amplifiers, with built-in
Dolby Pro-Logic decoders, are normally the most flexible option, and relatively
speaking not much more expensive than stand-alone decoders with prices starting
under £350. They have several advantages, including keeping the box count low
by providing up to five channels of amplification, enough to drive all of the
speakers in the system. AV amps also take control of the function and mode switching
for the other components in the system, and several models have built-in AM/FM
tuners as well, which helps simplify matters even further.
A growing number of AV amps also contain additional
digital signal processor (DSP) systems, to liven up non-Dolby encoded audio and
video material. DSPs simulate the acoustic properties of a wide range of
musical and theatrical venues, from open air stadia, to small intimate jazz
clubs, some are even based on actual measurements taken from renowned theatres
and opera-houses. DSP works by adding small amounts of reverberation (echo) and
delay to sounds coming from the speakers -- recreating reflected sounds that
give an impression of space -- and selectively filtering certain frequencies,
to mimic the reflective and absorptive characteristics of various types of building
materials and furnishings.
The next step up the ladder is a fully integrated
AV system, with the Dolby Surround decoder built in. They make a lot of sense
for those who do not have a hi-fi system to upgrade, do not want to use their existing
hi-fi for AV purposes, or shift speakers around every time they watch a movie.
Systems vary considerably in scope and performance, starting with the simplest
two-box minis costing around £750, rising to £1500 plus for systems that
include semi-exotic AV components, like
laser disc players, CD auto-changers or fancy speakers. One of the biggest
advantages with this kind of set-up is an integrated control system, usually
with the whole system operable form just one remote handset. This is home
cinema for the techno-cautious, they retain most of the flexibility of component
systems, but without the bother of
mixing and matching equipment from different manufacturers.
A lot of companies have cottoned on to the
fact that home cinema systems need extra speakers. The fact is, the extra
channels, which carry surround sound effects and dialogue, operate over quite
narrow frequency bands, at relatively low power levels, and you really don’t
need anything too fancy for that. Most reasonably competent book-shelf speakers
-- costing between £50 to £70 -- are perfectly adequate in this application. The
only thing to watch out for is the centre-front dialogue speaker, which needs
to be placed fairly close to the TV. It’s possible that the speaker magnet might
cause colour staining on the screen. In which case move it a little further
away; the staining should disappear quite quickly, all TVs have built-in ‘degauss’
coils which automatically demagnetise the screen every time it’s switched on.
If you’re really worried you can always get a magnetically shielded
centre-front speaker, they start at around £50 but try an ordinary one first.
There is still some debate over the
effectiveness, or otherwise, of specially designed AV speakers, and speaker
packages, that variously claim to create wider, narrower, longer or shorter
soundfields. The best advice we can give it to have a listen for yourself, but
only after you’ve heard what your own speakers can do first. If you think AV
speakers sound better have a go, but be prepared to bash the plastic, some of
these outfits can set you back £1000 or more, though cheaper ones are
available, from around £300 or so.
Dolby Surround decoders have popped up in all
sorts of places over the past few years, from VCRs to satellite tuners, but
after AV amps and Dolby systems the next most logical location is inside a TV.
This is the classic ‘one-box’ solution for those who do not want the
aggravation of connecting their hi-fi up to the VCR and TV, or maybe don’t even
have a hi-fi. There’s half a dozens models on the market right now, costing
from £800 upwards, and they all come with the necessary external speakers and
cables. They’re all very easy to set up and use but, it has to be said, are the
least effective sound-wise, due to the limitations of built-in speakers. However,
some models can be fitted with external speakers for the main stereo channels, then
they don’t sound half bad.
A WORD ABOUT TELEVISIONS
Whatever else you get you must have a proper
TV. Size does matter, it’s no good trying to build a home cinema system around
a 14-inch portable. Spectacular effects that sound as if they’re coming from
two streets away just don’t work when your eyes are focused on a squitty little
picture, that occupies just a fraction of your field of vision. Don’t mess about,
think big; what you need is a TV with at least a 25-inch screen. 28-inches is
better, but as general rule get the
biggest set your bank account and floorboards can stand, and if you’re serious
nothing less than 33-inches will do. Above that you’re into projection TV
territory, and it’s not just money you need, but a big dark room as well.
By all means get a NICAM stereo TV -- you
have little choice anyway on sets over 25-inches these days -- but it has to be said that most of them have
horrible little speakers that are set far too close to the screen to produce
any kind of stereo image, you’ll normally get a much better sound from separate
How about widescreen TV? The problem is there’s no widescreen material
to watch at the moment. A few movies shown on TV or on video are in a
letterboxed format, and widescreen TVs have the facility to blow them up to
full screen height and width, but this results in a drastic loss of definition,
a 405-line picture in fact, a real blast from the past... There’s a lot going
on behind the scenes right now, with digital transmission systems, high
definition, PAL-Plus and various other technical advances, so it might be a
good idea to wait for a year or so before you pour big bucks into a widescreen
TV. If you buy a widescreen set now be aware that it may not be possible to
update or upgrade it, if and when new technologies are introduced.
BOX COPY -- THE DOLBY STORY
There’s still a lot of confusion surrounding
Dolby Surround, starting with the terms Dolby Stereo, Dolby Surround and Dolby
Pro Logic. There’s no mystery. Movies shown in the cinema have Dolby Stereo
soundtracks, when they’re re-formatted for TV, or video, it becomes known as Dolby
Surround; made for TV programmes also have Dolby Surround soundtracks. Pro
Logic is the name of a high-performance decoder system, so far so good?
So what exactly is Dolby Surround? Basically
it’s a way of encoding four sound channels into a normal two-channel stereo
soundtrack. The beauty of it is Dolby information is very robust and can survive
intact on any reasonably good quality stereo recording or transmission system (VHS
hi-fi, NICAM, satellite stereo etc.). Moreover, it sounds perfectly normal on
conventional stereo equipment, but when it passes through a Dolby decoder the
extra two tracks can be heard as well.
The four channels consist of the right and
left hi-fi stereo channels, plus two lo-fi channels which carry sound effects,
heard through speakers behind or to the side of the viewer, and speech or dialogue.
The latter was originally intended to help focus a cinema audience’s attention on
the screen, no matter where they are sitting in the auditorium.
Ó R Maybury 1994 1907