Home-Theater Journal
Here I mean to reflect on experiences I have had assembling
and updating what is intended to be a relatively affordable
home-theater system. My working premise is that DVD-Video can
provide much better video and sound than other affordable TV
delivery systems and much more content at a much lower equipment
cost than HDTV. I think most consumers have yet to discover this,
or else they think it is hype, even though many already own their
first DVD player. The photograph below shows my system as it
exists today.
Video Configuration
The photo is dominated by a 32-inch Princeton
Graphics AR3.2T monitor, which I purchased about 2 years
ago.This monitor accepts cable and S-Video TV inputs and
personal-computer video signals up to XGA resolution. It does not
have component inputs, but I use the computer input for
progressive-scan DVD playback. You may be able to see the video
cable com
ing up to the
front panel (VGA-2) input from an IBM Netvista A40 micro-tower. I
purchased this computer on e-Bay about one year ago. It came with
a 4X AGP NVidea graphics card with 32 Mbytes of ram. The video
signal from this card is overlayed with DVD-Video by a Hollywood
Plus DVD/MPEG-2 playback card from Sigma Designs. The
computer came with only a CD-ROM drive, so I added an aftermarket
DVD-ROM drive. It is white but doesn't show because it is
insalled in a drive bay behind a door covering the upper front of
the computer.
Audio Configuration
The DVD/MPEG-2 playback card also delivers the digital sound
signal through an spdf ouput to a TECHNICS SH-AC500D Dolby AC3
SoundProcessor (decoder), which in turn is connected to a
Technics SA-AX6 Receiver. I needed the decoder when I installed
the computer instead of replacing my first DVD player, which had
stopped working. The rest of the sound system had been in place
for a couple of years before that. The receiver drives a passive
Technics SB-500 subwoofer and a Take5
home-theater set from Energy Loudspeakers. The Take5 system
was highly rated and the small size of these speakers made wall
mounting the left, right and surround speakers easy. You can see
the center speaker on top of the monitor and the left speaker on
the wall behind. I chose Technics components for the rest of the
audio system because I was eligible for a Panasonic employee
discount at the time. I don't claim to be an expert on audio
quality, but the system sounds very good to me, and it's amazing
how much sound can come out of those little speakers.
Video Problems
The current configuration works well most of the time, but I
have had to overcome a few problems and mistakes. The biggest
problem was to find a video configuration that realizes the high
image quality that is possible in DVD playback. I had another
32-inch set w
ith
480p capability and built-in scan doubler for about a year before
getting this one. Displaying the sharpness test pattern provided
on the Video Essentials disc[1] (from my original DVD player,
which didn't haveprogressive scan)showed annoying vestigal lines,
probably caused by ringing in the video amplifier. I was amused
when a service technician tuned in a weak channel and convinced
himself that he could see changes in the sharpness by looking at
the video noise. It turned out that the sharpness control on that
set didn't work at all.
My current set doesn't even have a sharpness control. It also
displays a poor sharpness test pattern through the S-Video input,
as shown in the picture above on the left. (It is a close up of a
small pair of lines at right angles at the center of the test
pattern.) However, the result using the VGA input, in the picture
on the right below, is much cleaner. 
Actually, the horizontal
black bar looks relatively clean in both cases because it is
determined by the vertical position of the electon beam. But the
problem with vertical lines as displayed with the S-Video input
is not subtle at all. The black line is surrounded by spurious
white lines that are evidently caused by errors in the video
amplifier in the "vision box" tacked on the back of the
set. There even seem to be second-order spurious black lines
outside the white ones.
The lesson I think I learned from all this is that one should
not assume that the bandwidth of a consumer-electronic video
system will or can be adjusted properly. However, a system
designed for personal-computer use has to work well in this
respect because text would look terrible otherwise.
Component Selection and Installation Problems
Our home theater is the family room in a 1960 vintage
split-level house, so most of the installation problems were
caused by lack of space and the need for everything to be black.
The paneling happened to have black vertical grooves, so I didn't
bother running the wires to the front left and right speakers
behind the wall. Instead, I just ran black electrical wire in
front of the grooves. I liked the idea of hiding those wires in
plain sight. The surround speakers are mounted near the ceiling,
but running the wires over the ceiling stumped me for a while.
Then I had the idea of pushing a leader through with my metal
measuring tape, which resists buckling to some extent. It wasn't
easy, but it finally worked. Later, my son told me that this is a
standard technique and there are special "fish tapes"
sold for the purpose.
The most natural place for the system is against a short
section of wall separating the family room from the basement. We
already had two chairs flanking the old tv there, leaving a
trapezoidal foot print for the system. It is wide enough for a
32-inch set, but not much wider at the front, so I needed a stand
of about the same width. I ended up cutting about 5 inches off
the right side of an Ikea tv stand to make it fit. The maximum
vertical space available is very close to 15 inches high, which
made finding a suitable omputer more difficult because most tower
computers were taller than this a year ago. (It would also have
been hard to fit a desktop case in the wider section because that
space was already occupied.) Fortunately, the IBM microtower is
available in black and just fits (with a little push).
Remote-Control Problems
Currently we have separate remote controls for the TV, VCR,
and AV receiver plus one more for the Hollywood Plus card. The AV
receiver can switch some of the video signals, but I found it
more natural to connect all the video sources directly to the TV
and use its remote to select video.. The audio is still switched
at the AV receiver, so selecting a source basically takes two
steps. Besides those two, when we are watching a DVD movie, I use
my Logitech cordless keyboard and mouse to get DVD playback
started, and then pick up a Hollywood Plus remote to navigate DVD
menus. Operating the system from all these controls or
front-panel inputs is a little inconvenient for me and a major
hassle for family members, so I will probably try to integrate
all the basic functions into a universal remote control sometime.
The cordless keyboard and mouse work ok from a coffee table
about 4 to 5 feet from the system, but not so reliably from the
couch behind the table. I may be able to find a better place for
the sensors that the remotes talk to with more experimentation. I
also have a Logitch
cordless joystick that operates at 2.4 GHz and has more range
and works well from the couch. I downloaded the demo version of
NASCAR 2002 to get the full effect of the system for gaming. I
thought the effect was better than arcade quality with the big
clear picture and loud stereo sound combined with the comfort of
the couch, but of course further improvements are still possible.
In particular, hardware and software are available that use all 6
speakers to create an even more intense 3D experience.
References
- Joe Kane, Video Essentials, see http://www.videoessentials.com
for latest information.
(last updated December 29, 2002)
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Copyright 2003, Terence J. Nelson