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Sanyo's big screen video
projector + Yamaha's
surround sound system=
4
S ILICON CHI P
This photo shows the dramatic
sweep of the picture available
from the Sanyo liquid crystal
video projector. For best
results, the room should be
completely darkened.
Would you like to bring the large screen & big sound of a
cinema into your home? Now you can, as we found when
we reviewed the combination of Sanyo's PLC-200PP
liquid crystal video projector and Yamaha's RX-V1050
stereo receiver with Dolby Pro-Logic surround sound.
By LEO SIMPSON
No matter how much you may enjoy movies
and documentaries on your TV set at home,
their impact is but a pale shadow of what you
see when you visit your local cinema. Big screen
and big sound is what you get at the cinema
and these are sadly lacking when you watch
the same programs at home.
Even if you have one of the later model TV
sets with screen sizes up to 80cm diagonal,
they are still small relative to what you see in a
cinema. And while you may have quite a respectable sound system, it is out of place with
a small screen.
The only remedy has been to obtain a video
projection system but these have been large,
unwieldy and expensive. Up until about 12
months ago, video projectors have all been
based on three high power CRTs which produce separate red, blue and green beams which
must be carefully converged and focused onto
a fixed screen. Now there is a new type of video
projector with 'just a single lens system. It is
simple to set up, takes only a moment to focus
and can be zoomed up or down to give the
picture size you want. Th ere are no bulky CRTs
(cathode ray tubes).
How do you produce a full colour video
picture if you do not employ one or three
CRTs? The answer is to use a completely new
technology based on liquid crystal panels. But
these panels are far removed from the everyday
liquid crystal displays used in watches, digital
M A RCH
1993
5
This photo of the projector shows the flip-up lid which conceals the controls,
although all functions can also be accessed by the remote control. The real
magic is in the liquid crystal panels concealed inside the chassis.
multimeters and a host of consumer
appliances.
Most LCDs are reflective but some
are backlit so that they can be seen at
night. The liquid crystal devices used
in the Sanyo video projector are transmissive which means that they work
in a similar way to a backlit LCD but
that is where the -comparison ends.
The diagram of Fig. l shows the general principle used.
Inside the projector is a 160 watt
metal halide discharge lamp which is
the sole light source for the projector.
It is fitted with a dichroic reflector
and its light output is directed through
filters which remove ultraviolet and
infrared (heat). The focused beam then
passes through a dichroic mirror
(DMl) which splits off (reflects) the
red light while allowing green and
blue light to pass through. The green
and blue light is then split in another
dichroic mirror (DMZ) so that now we
have three separate beams.
Each of the three beams is passed
through a liquid crystal panel which
has 110,450 pixels (picture elements)
and these individual picture elements
modulate the beam to make up the
picture. The modulated red, green and
blue beams are then combined into a
single beam by two further dichroic
mirrors (DM3 and DM4) and then
passed through the 67mm zoom lens
system to project onto the screen.
The above description is highly sim6
SILICON CHIP
plified and encompasses new technology which is breathtaking in its
scope. Just think of it: hundreds of
thousands of liquid crystal picture
elem ents being turned on and off with
refresh rates of 25 or 30Hz. Moreover,
the pixels are being constantly modulated so that they can provide a contrast range of 100:1. In essence, it is a
completely new technology for projecting a moving colour image onto a
screen and it has arrived at this advanced stage of development with almost no fanfare at all.
Projector features
Sanyo's PLC-200PP can be used in
virtually any room and can produce a
picture which ranges from 63cm
diagonal to 7.6 metres diagonal. The
smallest projection distance it will
allow is 2.3 metres from the lens to
the screen and since the zoom range
is 2:1 the picture size can range from
63q:n to 114cm diagonal. !Ii a larger
room, where the projection distance
might be say, 6 metres, the maximum
· picture size would be 3.4 metres diagonal.
That might not seem all that big
until you realise that the picture would
be about 2. 7 m etres wide and 2 metres
high. That's about as big as would be
practical in most homes, given the
standard ceiling height of 2.4 metres.
If you want a larger image, you will
need a much larger room and then
you tend to run out of brightness.
Even with smaller pictures, the most
impact is obtained with the room in
complete darkness - the same as in a
cinema.
Setting the unit up is dead simple
and you don't even need a screen - a
blank wall is ideal and it doesn't even
have to be white; a pastel colour will
do. You can use any PAL, SECAM or
NTSC video source and that includes
TV tuners, camcorders, VCRs and
laser disc players. All you do is set
the projector up on a table or bench
square to the wall and turn it on. The
lamp takes 30 seconds to come up to
full brilliance and during this time it
projects a blue image with the message "A MOMENT/UN MOMENTO"
together with a countdown in seconds to zero. After that, the video
signal can be seen on screen.
The projector has adjustable feet at
the front and a click-out foot at the
back so that it can be set up to project
down or up by 5°. With any normal
projector, whether film or video, this
leads to an image which is trapezoidal
rather than rectangular. However, the
Sanyo projector has electronic "keystone" correction so that the image
can be "squared up " simply by pushing a recessed button on the remote
control.
By the way, pushing any button on
the remote control or the equivalent
button on the projector brings up a
message on the screen. For example,
pushing one of the Focus buttons on
the remote control brings up "FOCUS"
on the screen and you can then precisely focus on that text.
Similarly, pushing one of the Zoom
buttons brings up "ZOOM" on the
screen and you can then adjust the
picture to size as required. Each onscreen message disappears after eight
seconds.
Remote control features
While all of the features of the projector can be operated by buttons
which are-underneath a flip-up cover
on the machine, it is far more convenient to use the remote control. This
can be used as a conventional infrared remote control or as a wired remote with a cable. While the wired
remote is tethered to the machine,
you don't have to worry about aiming
it in the general direction of the unit.
Since the Sanyo video projector
performs best in completely darkened
Sanyo's top of the range VHR-290 hifi stereo video recorder is an ideal program
source for the video projector. It is a very fast machine which means that you
don't spend any time waiting for it to put the picture on the screen.
rooms, it follows that a normal remote control is pretty useless because
you can't see the buttons. Sanyo has
recognised this by providing a remote
where all the buttons light up. Just
press the "Light Up" bar on the remote and all the buttons light up for a
period of five seconds.
Also on the remote control are buttons to turn the projector on and off,
select the video source, select the
video standard (auto, PAL, SECAM,
NTSC, adjust the sound level, mute
the sound, picture adjust (contrast,
sharpness, brightness, tint and colour
saturation), normalisation (restores
picture and sound to standard settings) and expand. This last button
allows the central portion of the image to be blown up to twice size which
may be useful in some circumstances.
All your settings are stored in
memory, so there is no need to go
through the set-up procedure each
time you turn on the projector unless,
of course, you have moved it to a
different position.
There is also an S-video socket and a
21-pin SCART socket.
The projector has an internal
speaker and 3 watt amplifier (mono
sound) and the remote control can be
used to adjust the sound, as noted
above. Interestingly, the remote control has no effect on the sound level if
an external amplifier and loudspeakers are used.
Styling of the unit is definitely low
key. While it is robustly built inside,
as it needs to be to maintain all those
mirrors and liquid crystal panels in
alignment, its outer plastic case is
Picture reversal
One feature which is not available
on the remote control but accessible
on the projector itself is picture reversal. This allows the machine to be
used in a rear projection set up.
On the rear of the projector are a
number of sockets for video and audio connections. There are three RCA
sockets for video plus audio left and
right inputs and a further two RCA
sockets for audio left and right connections to an external amplifier.
The rear of the video projector has
sockets for audio & video connections,
including S-video. The unit also has
an internal loudspeaker but using
external amplifiers & speakers gives
a much better result.
very subdued, finished in matt grey.
In fact, it looks a lot smaller than its
overall dimensions suggest. It measures 572mm from the lens cap to the
rear, 268mm wide and 253mm high.
It is also fairly heavy at 13kg but it is
quite comfortable to carry.
Lamp life
Metal halide lamps do not last as
long as CRTs but they are much longer
lived than conventional slide or movie
projector lamps. Sanyo recommends
lamp replacement at 2000 hours and
there is a LED which comes on when
this time has been reached.
Picture quality
Ah, now this is where we come to
the nub of the matter. In the past, it
has been accepted, by most people
who bothered to think about the subject, that for optimum picture presentation, you should sit far away enough
from your TV set so that the line structure is not readily apparent. Clearly, a
lot of people don't bother with this
and sit quite close to their TV sets.
With the very large picture presented by the Sanyo projector, the
line structure is clearly apparent. And
depending on how close you are to
the screen and how keen your sight
is, the individual pixels of the image
can also be seen.
Nor.is the picture quality really anything to write home about, if you are
judging it on a purely objective basis.
As you can imagine, if you blow up a
standard PAL picture by many times,
the limited video bandwidth is readily apparent in the relatively soft focus. It is certainly not high definition
TV and it is a long way short of the
best 35mm film images. On the other
MARCH
1993
7
Sanyo's flicker free video - how it works
There are many aspects of
Sanyo's PLC-200PP video projector
which beggar the imagination. For
example, most people who have any
knowledge of liquid crystal displays
know that are they digital in nature,
either fully on or fully off. But Sanyo's
110,450 pixel liquid crystal panels
produce the full range of colours expected from a standard colour TV
set and with a contrast range (bright
to dark) of 100:1. Just how does
Sanyo manage that?
And the projector copes with any
standard video source whether it is
PAL, NTSC or SECAM (or S-video).
The normal method of doing a full
video standards conversion would
be to incorporate a "frame store".
This would also enable the field rate
to be doubled (to 10OHz) and thus
avoid flicker which is otherwise very
troublesome on large screen sets.
But the Sanyo projector does not
have a field store for standards conversion and nor does it double the
vertical scan rate . And yet, that large
and dramatic screen is completely
free of flicker, in spite of being
scanned at the normal 50Hz rate for
PAL sources.
Let's consider how the liquid crystal panels are driven first. Each of
the pixels is controlled by its own thin
film transistor (TFT) which is on the
pixel itself (ie, the light passes
through it. Each TFT is essentially a
Mosfet which naturally has a fairly
substantial gate capacitance and this
provides a sample-and-hold facility.
The gate of each TFT is supplied
with a sample of the video signal and
this signal is analog which means
that the transistor does not have to
be either on or off, it can also be
anywhere in between and hence the
"twisted nematic" fluid of the pixel
can be anywhere between fully transmissive and opaque.
hand, in view of the poorly fo cused
images you see in man y cinemas, th e
Sanyo projector stands up pretty well
by comparison.
So on a purely objective assessment,
concerned with line and pixel structure and video bandwid th, the picture quality is pretty ordinary. However, that is not the end of the matter
by a long shot. The strong point of the
Sanyo video projector is that it produces such a large and bright picture
and furth ermore, it is completely
fli cker-free.
The simple fac t is that, after watching that dramatically' large picture for
a few minutes, line and pixel structure becomes unimportant. You become so engrossed in the program
that you just don 't notice the line
structure.
8
SILICO N CHJ P
Sample & hold
But why doesn't the picture flicker?
The answer is because of that "sample and hold" facility on the gate of
each TFT. In a normal television picture tube, the image is created line
by line, with the electron beam scanning rapidly over the picture tube. In
the 625-line PAL system, the image
is scanned at 50Hz, alternating between odd and even lines which build
up a complete frame in 1125th of a
second. After the electron beam has
passed over a particular spot on the
tube, the phosphors will continue to
emit light for a brief period of time but
the system also depends on persistence of vision so that we see a constant image on the screen.
However, while the screen may be
Sound quality
Sound quality is a most important
factor. While the Sanyo projector does
have an inbuilt speaker, its mono output quality is no more than could be
expected and it also has to compete
with the noise of the internal cooling
fans. To do justice to the system , you
need good quality stereo sound at the
very least. That means that any video
source you are using shoul d provide
stereo sound.
For the purpose of our review, we
used a Sanyo VHR 290 video recorder
with hifi stereo sound. This VCR is
the flagship of Sanyo's range and has
scanned at 50Hz (the field rate), the
complete image is updated at 25Hz
and this leads to residual flicker which
can be very noticeable on bright parts ,
of the screen.
In the Sanyo projector, the pixels
are split between odd and even lines
and they build up the picture in the
same way as in a cathode ray tube.
The difference is that whereas the
image from a picture tube depends
on phosphor spots which are excited
very briefly every 1125th of a second,
each pixel TFT is fed a sample of
video signal every 1125th of a second and its stays turned on to that
value until it receives the next video
sample.
Thus, most of the pixels of the
screen stay on all the time, constantly transmitting light at whatever
the required value is and only changing if the signal changes. This means
that there is no apparent flicker in the
picture at all.
Standards conversion
So how does Sanyo manage video
standards conversion without resorting to a frame store? In essence, the
projector is designed to the American NTSC standard as far as line
scan rate is concerned. This means
that the picture is essentially 525
lines with a field rate of 60Hz for
just about every feature you could
want. If you want a first class video
signal with stereo sound, whether "off
air" via its inbuilt tuner or from tape,
it is the ideal source to team with the
Sanyo PLC-200PP video projector.
With the program source catered
for, we still had the problem of the
amplifier and loudspeaker system. To
do the Sanyo projector full justice,
you really should settle for nothing
less than a system which can produce
full surround sound. To obtain that
from pre-recorded video tapes , that
means you need an amplifier system
which has Dolby's Pro-Logic decoder.
Anything less is just short-changing
the system .
Sanyo do not have a surround sound
Red panel
Projection lens
Dichroic
reflector
LCD panel
Condenser lens
Fig.1: the Sanyo
projector uses four
dichroic mirrors to
first split the light
beam from the metal
halide lamp & then to
recombine the red,•
green & blue beams
after they have been
modulated by the
liquid crystal panels.
Ultraviolet filter
NTSC program material and 50Hz
for PAL material. To convert 625-line
PAL pictures to 525 lines, the projector could do it by simply omitting one
line in every six but this wou ld lead to
jagged diagonal lines on the screen .
Instead, the conversion is done by
means of a "line store" (much simpler than a frame store) and a complex averaging scheme is used. For
example, the first PAL line becomes
the first NTSC line. The second
NTSC line is a combination of 4/5ths
of the 2nd PAL line and 115th of the
3rd PAL line. The third NTSC line
becomes 3/5ths of the 3rd PAL line
and 2/5ths of the 4th PAL line. The
4th PAL line becomes 2/5ths of the
4th PAL line and 3/5ths of the 5th
PAL line. Finally, the 5th NTSC line
becomes 115th of the 5th PAL and
4/5ths of the 6th PAL line. The process then repeats. Get the picture?
When you thin k about it, while the
Sanyo projector does not use a frame
store to do the standards conversion , the LCD panels themselves are
effectively a frame store. After all ,
they hold the video signal constant
between each update, which happens every 1125th of a second.
amplifier so we turned tOYamaha and
arranged for the loan of their RXV1050 AM/FM stereo A/V receiver. If
ever a product was made to complement the Sanyo projector, this Yamaha
stereo receiver is it. It not only incorporates Dolby Pro-Logic decoding but
also has has digital sound fi eld processing, as pion eered in the Yamaha
DSP-1 a few years ago.
With five amplifie r ch annels to
drive front , rear and middle speakers,
the DSP system can imitate the reverberation times of large and small concert halls. Not only that but the RXV1050 is also designed to switch video
program sources so that it can handle
video and audio signals from three
sources; it even has S-video inputs.
This makes it ideal as the program
selector for the Sanyo projector.
We set u p the San yo projector and
Yam aha surround sound amplifi er
combination with Dynaudio Image 4s
as the main lou dspeakers (to be reviewed in a future issue), together
with Yamaha NS-A102s as the rear
speakers an d a Yamaha NS-Cl 10 as
the centre effect speaker. Also hooked
into the system was a Yamaha CD
player.
All of this equipment was set up in
the reviewer's home, in a room measuring about 4.8 x 3.6 metres. This
room is normally used as a music
listening room and so is ideal fo r a
"h ome cinema" . Th e final essential
ingredients were a number of video
Dichroic mirrors
As Fig .1 shows, the Sanyo projector uses four dichroic mirrors to first
split the light beam from the metal
halide lamp and then to recombine
the red, green and blue beams after
they have been modulated by the
liquid crystal panels. However, some
readers may wonder why the lamp
reflector is also labelled as being
dichroic. How and why should a simple lamp reflector be dichroic? Should
it not reflect all light equally well?
The answer is that a dichroic mirror reflects some light and passes
through the remainder. In the case of
the lamp reflector, it reflects all light
up into the ultraviolet range but most
of the infrared (ie, heat) passes
through it. This needs to be the case
because the liquid crystal panels cannot stand very much heat. That is
why there are also UV and infrared
filters in front of the lamp. In fact , the
liquid crystal panels can only withstand a maximum temperature of
80°C. Contrast that with the bulb
temperature of the metal halide lamp
which normally runs at 1000°C. No
wander the projector has two fans to
keep the interior cool.
tapes of current action movies with
lots of special effects and featuring
Dolby Surround Sound.
Audio/video integration
With all of these factors brought
together, the system really comes to
life and is capable of providing an
entertainment experience every bit as
dram atic as that experienced in any
picture theatre. The large screen is
good, for all the reasons we have listed
above, but it really needs a full range
surround sound system for maximum
impact.
Once you sat down in the darkened
room and pressed the play button on
the VCR remote control to start the
program you were then immersed in a
MARCH
1993
9
Yamaha's RX-V1050
stereo receiver offers full
Dolby Pro-Logic
decoding & DSP to give a
variety of surround
sound environments. It
has five amplifiers with
a total power output of
390 watts into 8 ohms. It
also has 40 preset AM/
FM stations & a
comprehensive remote
control with "learning"
facilities.
complete cinema experience. The
larger than life-size images combined
with spectacular surround sound
make it all happen. Switching on the
lights at the end of the program is just
like emerging from a theatre and coming back to everyday reality - it's that
good.
In fact, with this combination of
the Sanyo video projector and the
YamahaRX-V1050 stereo receiver, we
finally have achieved the "audio/
video integration" that the Japanese
manufacturers have been talking about
for years.
Sound simulation
Yamaha's RX-V1050 could be the
subject of a complete review just by
itself as it has so many features. With
Dolby Surround Sound, the dialogue
comes from the front speakers (in
stereo) while music and sound effects
come from the front, rear and centre
channels to give dramatic reinforcement to the visual happenings.
Yamaha has also added Enhanced
Dolby mode which, as the name suggests, beefs up the sound effects. As
well, there is Concert Video, Mono
Movie, Rock Concert and Concert Hall
effects. Concert Video is intended for
movie soundtracks with stereo but
without Dolby. Mono Movie is good
for ordinary VCR tapes with mono
sound - it gives a good simulated
stereo spread.
Rock Concert and Concert Hall are,
as the names suggest, mainly intended
for listening to music rather than as
accompaniment to video but there is
10
SILICON CHIP
no reason why they could not be used
to provide the sound field for music
videos, both rock and classical. And
if you want to dispense with any enhancement, you can always listen to
your music in unadorned stereo.
be written the programmed functions.
Naturally, it could be used to control
both the Sanyo projector and VCR.
Now if we had remote controlled room
lighting as well, we would have total
bliss!
Juggling the remotes
Closing thoughts
And now to a few practicalities.
Ever had the feeling that your remote
controls were conspiring against you?
They have the habit of hiding underneath the couch, underneath papers
on the coffee table or even sliding
behind cushions so that you go
through enormous frustration when
you suddenly need them. Well, home
theatre is like that only worse.
Each piece of equipment used in
the above setup has its own remote
control and only the one for the Sanyo
projector has buttons which light up.
In a darkened room, you then have
the added complication of not being
able to see which buttons to press, as
well as the problem of finding the
right remote control in the first place.
The remote control for the Yamaha
stereo receiver is a partial solution.
As well as controlling its own extensive range of features, it can be used
to control a Yamaha CD player and
cassette deck so that meant I was not
forced to use the remote control for
my CD player. Still, you can't see the
buttons in the dark.
Furthermore, the Yamaha receiver's remote control has learning functions so that it can also be programmed
to control other appliances. It comes
with paper templates on which can
So what is the overall picture? In
our opinion, the Sanyo video projector will find a ready market both in
teaching and training institutions, as
well as in the home. In teaching applications, the internal speaker in the
projector is adequate although a modest stereo setup with speakers either
side of the screen is a big improvement.
In the home, you really need to go
for the full Sanyo and Yamaha combination. Going for one without the other
would be a waste of money and even
then, it is a choice which will only be
available to the well-off. The recommended retail price of the Sanyo PLC200PP is $7499 while the RRP of the
Sanyo-290R hifi stereo VCR is $899.00.
The Yamaha RX-V1050 stereo receiver
is $1399. To those figures must be
added the cost of main and surround
sound loudspeakers.
For further information on the
Sanyo video projector and hifi stereo
VCR, contact Sanyo Australia Pty Ltd,
PO Box 401 , Homebush, NSW 2140.
Phone (02) 763 3822. For further information on the range of Yamaha surround sound equipment, contact
Yamaha Music Australia Pty Ltd, 1733 Market Street, South Melbourne
Vic 3205. Phone (03) 699 2388.
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