HOW TO BUY.... HOME
1. AV AMPS/DECODERS
The consumer electronics industry is getting much better at
packaging home cinema equipment and there are some excellent Ďone-boxí systems around
at the moment. However, all of them
involve some sort of compromise on performance or flexibility, or it may simply
be that youíre not in the market for a new TV, satellite receiver or hi-fi
system right now. If youíre going to do the job properly then you have to think
about building a system around carefully selected components, and the logical
place to start is an integrated AV amplifier and surround-sound decoder.
AV amps come in a variety of flavours, from modestly
equipped budget models costing less than £250, to serious high-end designs,
with THX and AC-3 capabilities. Bear that in mind if you have a
reasonably-sized budget, i.e. more than £700 to spend. DVD is coming and if you decide to upgrade
in the near future a multi-channel amp will make life a lot easier, and it
could save you a packet on further upgrades.
Output power is one of the first things to consider, taking
into account the speakers youíre going to use it with, but remember, more
doesnít necessarily mean better. Donít just look at the ratings for right and
left stereo channels, the centre and rear channels are equally important. They
need to be on a near-equal footing with the front channels, or at least in the
same ballpark, otherwise the system could lack impact and it might be difficult
to achieve a balanced soundfield.
Most mid-range AV amplifiers come equipped with a set of
digital sound processor (DSP) modes, that generate a range of pseudo surround
effects, or simulate the acoustic properties of a variety of venues. They can
be quite effective, especially with mono sources, lightly engineered stereo
material and older audio recordings, but donít get carried away. Once the
novelty has worn off itís unlikely youíll use them very much.
The Dolby Pro Logic decoders in most AV amplifiers have
similar facilities, but some are easier to set up and use than others. At the
very least there should be some means of independently adjusting levels on the
front, centre and rear channels. An input level adjustment is useful too, to
compensate for the differences between soundtrack recording levels. They vary a
lot, and it can be especially noticeable on action blockbuster movies, where
there is a wide dynamic range, between quieter sounds, and loud explosions or
AV amplifiers have to be able to handle a number of source
components, not just the obvious ones, like a VCR, satellite tuner and
laserdisc player; you may also want to use it with a video games console,
camcorder, audio components and heaven knows what else in the next five years,
so check thereís sufficient input sockets. Aim to have at least one or two
spares when all of your system components have been accounted for.
A growing number of AV amplifiers now come with built-in
AM/FM receivers. If youíre not committed to a particular receiver theyíre definitely worth thinking about; at
the very least it means one less box in the system.
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* Output power is a consideration, but itís more important
thereís not a big difference between the front, centre and rear channels,
otherwise the system can be difficult to balance
* Lots of clever digital effects can be fun, but ask
yourself, do you really need them, and how often will they be used?
* You can live without remote control on most pieces of
audio and video equipment, but not a surround-sound system
* An AV amp needs input sockets, and plenty of them,
otherwise youíll be forever swapping cables
* Think ahead if youíre planning to splash out on an AV amp.
You might not have AC-3 or MPEG Audio sources -- like DVD or laserdisc -- right
now, but in a yearís time, who knows?
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Kenwood KR-V99OD, £1300, HE38. An accomplished and
solidly-built AV amp, ready and waiting for AC-3/MPEG audio. Thereís plenty of
DSP effects to play around with and it has a very competent DPL decoder, that
copes equally well all kinds of movie soundtracks, from moody atmospherics to
floor shaking explosions
Philips FR-751, £300 HE41. If youíre on a tight budget or
just dipping your toes in the water, then this unusually well specified AV
amp/receiver is worth shortlisting. Power distribution is good and DPL
resolution is sharp. A slightly thin bass and a shortage of input sockets knock
off a couple of points though.
Sony TA-VA8ES, £700, HE40. Sony may have gone a little over
the top with all the DSP effects, but theyíve got everything else about right,
including a set of inputs for AC-3/MPEG audio. Itís a lump of a thing, but it
packs a real punch and the DPL decoder is a treat.
2. AV DECODERS
If youíve just spent a considerable amount of time, money
and effort getting your component hi-fi system to sound just right, the last
thing you want to do is replace a cherished amplifier to upgrade to home cinema
operation. You donít have to, stand-alone Dolby Pro-Logic decoders are designed
to integrate with any type of hi-fi set-up, with a minimum of disruption, and
without compromising performance. Indeed, a DPL decoder is the only logical
route, if youíre pursuing the very best home cinema has to offer.
As far as the hi-fi system is concerned, a DPL decoder is
simply another audio source component. Interconnections are generally quite
straightforward. DPL decoders have one or more stereo line-level inputs, which
connect to the audio output of the AV source components, (usually a NICAM VCR,
satellite receiver or laserdisc player). Most dedicated decoders have four
line-level outputs; two are for the front right and left stereo channels; these
go to one of the hi-fi amplifierís auxiliary inputs. The other two outputs are
for the centre-front dialogue channel, and the rear-effects channel. Theyíre
connected to a separate stereo, (or two mono) power amplifiers, driving the
centre channel speaker and two rear-effects speakers.
Most other DPL decoders have their own built-in power
amplifiers, to directly drive speakers for the centre, and more often than not,
the effects channel as well. Power outputs vary widely, but itís a good ideal
to choose one that roughly matches the output from the main hi-fi amplifier; if
necessary err on the side of caution. Several top-end decoders are THX
certified and/or AC-3 ready, thatís clearly a consideration if the rest of your
system makes the grade, or you plan to upgrade at some point.
A number of DPL decoders are equipped with digital signal
processors (DSP) facilities. Theyíre used to create surround-sound and spatial
effects from non-Dolby encoded stereo and mono material. The results can be
quite interesting but theyíre not a substitute for the real thing and shouldnít
divert attention away from surround-sound performance.
Itís important to have an adequate number of input sockets,
to meet present and future needs. A minimum of two are required for most
set-ups, to cater for a VCR and satellite receiver, though it may be possible
to route AV inputs through either the VCR or satellite receiver, if they can be
connected together using SCART to SCART AV cables. In that case stereo audio from the active component is
automatically passed through to the decoder input. Donít worry too much about
video inputs and outputs, theyíre mostly a convenience feature, to assist with
cabling, and in most cases video signals pass in and out of the unit without
being affected in any way.
The majority of decoders are simple to operate; models with
independently adjustable input and output levels are the most flexible, better
able to integrate with a system, and help create the most dramatic and natural
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* Performance and prices vary widely, try to match the
decoder to the capabilities of your hi-fi. A top-end decoder would be largely
wasted on a system based around a mediocre hi-fi and cheap VCR
* If youíre choosing a decoder with built-in amplification
try to match the centre and rear channel outputs with that of your main stereo
* You will need at least two input channels, three or four
will leave you some room for expansion
* A remote control facility is essential, unless you enjoy
having to keep getting up to adjust levels
* THX and AC-3 facilities are clearly worth having, just
make sure the rest of you system is up to it
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Angstrom 200, £3495, HE37. And worth every penny, providing
youíve got a hi-fi system to match! Itís in a class of its own. The processor
effortless resolves all of the information contained on a soundtrack, but with
a smoothness, subtlety and articulation thatís missing on lesser decoders. It
leaves you in no doubt that youíre experiencing precisely what the director and
sound engineers wanted you to hear.
Mission Cyrus AV Master, £650, HE37. A potent mid-range
decoder, with on-board amplification for the centre dialogue channel. Itís
uncommonly flexible, and can be programmed to function in a wide variety of
configurations. Features include an auto set-up and various DSP modes. A worthy
companion for other Mission components.
Sony SDP-E300, £230, HE37. This is the cheapest DPL decoder
to earn the coveted HE stamp of approval; itís well specified and very
flexible, with a comprehensive set of input and output socketry. Rear channel
amplification is a little lightweight but the processor is fast and accurate
with good centre-channel resolution.
3. HOME CINEMA SPEAKERS
A mystique has grown up around home cinema loudspeakers in
the past few years. Itís partly to do with the way some manufacturers have
latched onto this rapidly growing market, and the slightly unusual way in which
they are used. In most respects, however, AV speakers are no different to any
other kind of hi-fi loudspeaker, either technically or operationally. Thereís good
ones, bad ones, and all the others in between.
That said there are a few specialist design features, unique
to some types of AV speaker, which weíll be looking at in more detail in a
moment. The way in which AV speakers are deployed is also different to most
other types of audio system. The aim is to surround the viewer with sound, consequently
there are more of them.
In a typical Dolby Pro Logic set-up there will be five,
sometimes six loudspeakers. Two are used for the right and left stereo channels.
The third speaker is for the centre-front channel. Speakers four and five carry
rear-channel surround effects. The sixth speaker is an optional sub-woofer,
used to boost or supplement the bass output of the front stereo channels.
The right and left stereo speakers are usually placed a
couple of feet either side of the TV screen, facing the viewer. They operate in
precisely the same manner, handling the same kinds of frequencies and power
levels, as normal hi-fi speakers and because theyíre some distance from the
screen, magnetic shielding is usually unnecessary.
The centre-channel speaker is the odd man out. It has to work very hard and spends much of
the time handling dialogue. Itís not a demanding job sonically, but it helps if
itís moderately directional as its job is to focus the viewers attention on the
screen. Centre-channel speakers are normally placed quite close to the screen,
so this is one instance where magnetic shielding may be required, to prevent
colour staining on the picture tube. In fact thereís nothing new about magnetic
shielding, ordinary TV speakers have been that way since day one. Shielding
requires no magic, advanced technologies or a huge increase in manufacturing
costs, usually just a second magnet, to minimise radiated fields.
Itís important to choose a centre speaker that compliments
the main stereo speakers, both in terms of tonality and dynamic range,
otherwise the dialogue component of the soundfield can appear artificial or disjointed.
The aim with rear channel speakers is to create as diffuse a
soundfield as possible, so the viewer canít pinpoint where the sounds are
coming from. Some weird and wacky designs have emerged, though conventional compact
enclosures, carefully sited a couple of feet behind, and a foot or two above
ear level, are normally quite satisfactory. The rear-channel has a limited
bandwidth, that tails off rapidly above 7kHz, so they donít need especially sophisticated
Movie soundtracks, unlike most other forms of audio
recording, often contain large amounts of bass information, to create an
effect, and emphasise whatís happening on the screen. To that end itís
sometimes desirable to have a separate bass loudspeaker or sub-woofer. Normally
only one is needed as low frequency sounds are not as directional as higher
frequencies, though a lot of home cinema aficionados and experts recommended
the use of two subs, to spread bass sounds more evenly.
There are two types of sub-woofer. The simplest, (though not
necessarily the cheapest) are Ďpassiveí subs, Theyíre driven -- via a filter
circuit -- from the right and left stereo channels, or from a dedicated
sub-woofer output on the amplifier. Active sub-woofers have their own built-in
amplification, which relieves some of the strain on the main amplifier, and
simplifies speaker matching. It also enables much higher power outputs, than
would normally be possible using just the main AV amplifier on its own.
AV loudspeakers have something else in common with most
other types of hi-fi speakers, you get what you pay for. If you pay peanuts,
you could end up with something that sounds like barrel load of monkeys...
Centre speakers are a case in point, and itís worth spending a little extra on
one thatís designed to do that single, rigidly defined job. The B&W CC3,
which sells for around £150, is a good example of that kind of specialisation.
The combination of B&Wís ĎPrismí enclosure helps stabilise the sound output
by eliminating internal reflections; two high quality drive units and a single
tweeter produce a crisp and finely articulated sound that is well suited to
Rear channel speakers donít have to be complicated and the
bottom line is that almost any competent hi-fi speaker will do the job.
Nevertheless, speaker manufacturers have risen to the challenge and various designs
have appeared, that provide extra dispersion, to help spread the sound. One of
the best and most successful has been the Canon SV-15. They use an acoustic Ďmirrorí
to help distribute the sound outwards, and downwards, so theyíre ideal for wall
mounting. Recent price reductions, to around £100 a pair, makes them reasonable
Active sub-woofers have become one of the most popular home
cinema add-ons, and itís not difficult to see why. Action blockbusters and sci-fi
epics come alive with gut-rumbling effects, that most conventional hi-fi
speakers simply cannot replicate. One of the best examples of what can be done
-- for a relatively modest outlay -- is the REL -50, currently selling for
around £375. Itís rated at 50 watts, a manageable amount of power, thatís controlled,
without sounding brash or coloured.
Comparatively few stereo speakers manage to bridge the gap between
hi-fi and home cinema. Polk Audioís RT10 are one of the rare exceptions, and at
£480 theyíre relatively affordable. Theyíre superbly well qualified for Dolby Pro-Logic
duties with impressive bass capabilities, but their transparency and fluency means
they can handle almost any kind of material with equal conviction.
Shopping for AV speakers separately can be a little daunting
but donít be put off, and never buy anything without hearing it first. However,
if you want to avoid the hassle of mixing and matching, check out the growing
number of package systems now available. Theyíre a very convenient way of
buying speakers, but donít loose sight of the operational points weíve outlined,
and donít expect any discounts for quantity, at least not on any packages worth
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SYSTEM BEST BUYS
* B&W 600 SERIES, £900, HE34. Although not conceived as
a package, this collection of specialist AV speakers hangs together really
well. DPL and stereo performances are consistently good and the CC6 centre
speaker delivers an unusually assertive bass
* DEFINITIVE TECHNOLOGY/MK SYSTEM, £2645, HE27. A highly successful
marriage between Definitive Technologyís articulate BP8 column speakers, CLR
centre speaker, BP1 compact bi-polars and M&Kís gutsy sub-woofer. A unique
blend of power with precision and subtle clarity. A true jack of all trades,
equally happy with stereo and Dolby sources
* MISSION AV1, £330, HE37. A real value for money package, based
around Mission 73 speakers and a matching passive sub-woofer. Its strength lies
in the systemís simplicity and clear, accurate and detailed mid-range delivery.
It has its faults, but if youíre looking for a tidy and cost-effective starter
package, look no further
R. Maybury 1996 1111