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September 2002. Welcome
back. It's been twenty-seven months since I reported on
any significant changes in my home theater and it's been
almost six years since I purchased my reference DVD player.
With the intervening introduction of great progressive players
and EX capable audio decoders, I think you might agree that
I was overdue for an upgrade.
The DVD
Player
Since DVD's March '97 seven-city rollout, my player of
choice has been the Sony DVP-S7000; Sony has yet to produce
a player that rivals its interlaced picture quality. To
transform the 7000's interlaced video to progressive video,
I used a Faroudja LD-100 Line Doubler, the piece of equipment
that originally inspired me to believe that a film-like
presentation was possible at home. As satisfying and revealing
as this combination has been, it also has its limitations.
Published
reports show that the Sony's video frequency response
is down only 1.5 dB at 5 MHz, but continues to decline as
the response approaches the limit of DVD's frequency content
(6.75 MHz). So while fine textures and small details are
far from invisible, they are a tad suppressed. There's also
an issue related to the Faroudja's processing, which causes
an interference pattern within the 6.75 MHz circle of an
AVIA resolution test pattern. And I've been forced
to assess DTS audio tracks on an auxiliary Panasonic DVD
player since the 7000 isn't DTS-capable.
I've been watching progressive chip set technology mature
and finally, as 2002 was drawing to a close, I decided that
it was time to buy a new player. Unfortunately, hard test
data describing DVD player performance is rather hard to
find these days. Very few of the slick magazines publish
test bench numbers any more. Even ñThe Perfect Vision,î
once the most visible (no pun intended) advocate of achieving
the best possible performance in home theater, ceased to
publish player test-bench results. TPV's current player
reviews are purely subjective, no more helpful than ñAudio
Video Interiors.î ñSound & Visionî continues to publish
analytic test reports, and the Secrets of Home Theater web
site (SoHT) is also very helpful. But S&V doesn't
address the Chroma
Upsampling Error or ringing in the anti-aliasing
filter (which I'll explain briefly). And while SoHT addresses
both, it publishes hard data so infrequently that I simply
couldn't wait. What's this obsessive home theater enthusiast
to do? Something odd.
I grabbed
my oscilloscope, two 75-ohm cables, two pass-through BNC
terminators, a few appropriate 75-ohm adaptors, the AVIA
Guide to Home Theater DVD, the Toy Story DVD,
and headed for my local home electronics stores. I was amazed to find that in every store in
which I asked, the salesman or store manager allowed me
to connect its floor samples to my ïscope to test the players
of interest. I spent a couple of hours in each store, measuring and noting my
results, moving from one candidate player to another, much
to the amusement and bewilderment of the sales staff. Not surprisingly, in every store I was told that
my antics were a completely new experience for them. What was I looking for? Published
reports revealed enough about various players' performance
(frequency response, signal-to-noise ratio, Y-C delays,
and so on) to limit my interest to a short list of about
five candidates. I
knew that some didn't have the chroma upsampling error,
but others were unknown, so I first observed the Toy
Story main menu screen on the most revealing CRT-based,
HDTV rear projector each store had. That was easy. I
then verified the players' frequency responses on the ïscope
using AVIA's multiburst advanced video test pattern,
found at Resolution / Multiburst, and observed AVIA's
widescreen enhanced resolution pattern, found at Widescreen
Enhanced / Resolution, taking particular note of the 6.75
MHz circle on the lower right. That was less critical, since I had already read
published video frequency response findings. Next came my single most important measurement,
overwhelmingly ignored, video ringing in the anti-aliasing
filter. Readers
of my DVD reviews know that I always comment on edge halos,
those pesky outlines seen at high contrast transitions in
the video, which are either an MPEG-2 artifact or an intentional
attempt to sharpen the image artificially (or sometimes
both). I continue
to maintain that edge halos are the single greatest impediment
to a film-like presentation at home, so I wanted to avoid
any player that worsened or caused halos in hardware. If you're curious, I'll try to explain the problem
as succinctly as I can (for everyone else, feel free to
jump to the next paragraph). Unique problems occur at the points of entry and
exit in all sampled systems - digital video systems among
them. The input
analog-to-digital converter must avoid data frequency content
higher than half the sampling rate; if present, such data
will ñfold overî and cause nasty-looking distortions. This phenomenon is called aliasing. Similarly, there are residual high frequency sample
rate contaminants at the digital-to-analog converted outputs
of digital systems. Filters are applied at such inputs and outputs
to remove offending signal content. Input filters are found on the professional equipment
used to create content; that's out of our control but they
tend to be very high quality, so it's not a concern. But the way video output filters are implemented
in consumer-grade DVD players can cause a damped oscillation
or ringing in the video.
Onscreen, video ringing looks just like edge halos. An
initial half cycle of overshoot will appear as a bright
halo around a dark object. An additional half cycle of rebound
undershoot will put a dark halo around the first bright
halo, and so on. So for my next in-store test, I navigated
to one of AVIA's 50 IRE test patterns, found at Gray
Scale & Levels / Black and White Levels / Black Bars
+ Half Gray, and looked at the video transition on the ïscope.
(I had confirmed previously that there is no ringing on
the disc by performing a screen capture on my computer and
magnifying the image.) Sure enough, on the ïscope's screen,
ringing revealed. For each player, I noted the number of
half-cycles, and their amplitudes and widths. After I had
finished all my measurements, I looked at my data and factored
in published measurements; my initial leading candidate
had been eliminated. This was a great disappointment, since
the price of that player was reasonable. (I also had hoped
that the winning player would have the Sage/Faroudja chip
set; that was not to be, but Silicon Image does a fine job
as well.) The player that came out on top was the obnoxiously
expensive Denon DVD-9000.
Sigh.
Okay, at this point you're probably asking yourself what
does this have to do with me? I wouldn't expect you to buy
an oscilloscope and to duplicate my nonsense when you find
yourself in the market for a new player, so here's what
I'd suggest. Before you begin, read test reports that contain
hard data; put together a short list of leading candidates
that have the best performance for your target budget. If
you don't already have the AVIA Guide to Home Theater
DVD, pick one up; you should own one to set up your display
properly anyway. When you visit brick & mortar shops
to assess players, make sure they're connected to a fine
CRT-based, HDTV rear projector's 480p (progressive) component
video inputs, and make sure that each player is in the progressive
mode. (Even if you currently don't have a display that can
accept progressive video, trust me, you eventually will.
Plan on buying a progressive player.) Make sure that the
display's scan velocity modulation (SVM) is disabled and
that the sharpness is at the nominal setting. SVM may be
considered another form of artificial image sharpening and
it, too, adds halos to the image. If the display doesn't
offer the option of turning SVM off, ask to see the player
on a display that can disable SVM. (And if possible, you
should consider turning SVM off at home.) Check AVIA's
widescreen enhanced resolution pattern; every frequency
(they are labeled and appear as increasingly tighter spaced
vertical bars within circles) should be clear, particularly
within the 6.75 MHz circle. Take a look at both the sharpness
test pattern, found at Resolution / Sharpness, and the Black
Bars + Half Gray test pattern. Observe the halos. Notice
widths and subjective halo brightness. Then display the
main menu from Toy Story and look for banding (see
the Chroma
Upsampling Error article). Seriously consider purchasing
the player that has a flat and extended frequency response,
no chroma upsampling error, and rings the least. That's
the player that should come closest to providing a film-like
presentation.
The Transcoder
So I bring my new treasure home and eagerly connect the DVD
player to my system. I can now bypass the Faroudja and connect
the component video outputs from the Denon directly to the
Extron CVC200 component-to-RGB-HV converter (transcoder).
I pop the AVIA disc into the player for a quick performance
check and, as I navigate, I'm immediately struck with the
speed of the player's drive. It snaps from screen to screen;
layer transitions should be virtually invisible, an added
bonus. All the test patterns look fine, so I replace the AVIA
disc with arguably the best-looking DVD to date, and certainly
the best-looking of 2002, Star Wars Episode II: Attack
of the Clones. I jump to a chapter at random and sit back,
smiling in anticipation. Uh, oh. What's that? The contrast
is changing, cycling up and down every twenty seconds. Twenty
seconds? Damn! It's the cursed Macrovision! I quickly replace
AOTC with Harry Potter and the Sorcerer's Stone,
famously free of Macrovision. A lovely stable picture, wonderfully
detailed.
Is the
problem in my projector? The new player? Is it the transcoder? Out comes the oscilloscope. I connect the Y-output from the Denon to the
ïscope's channel A and examine the R, G, and B outputs of
the Extron on the ïscope's channel B. There they are, the Macrovision pulses from the Denon's
Y-output, obscenely thrusting up and down. And on Extron's R, G, & B outputs, the video
gain rises and falls synchronous with Macrovision. Damn! A
quick bit of web research revealed that Macrovision has
been required on the component video outputs for some time;
the earliest reference I found is for the Sony DVP-S9000,
introduced years ago. More
studio paranoia. To
the best of my knowledge, the only devices currently available
that can record 480p analog component video are horrendously
expensive D5 professional digital VCRs. Professional pirates may own a D5 machine,
but it's unlikely that a consumer - even one as crazy as
yours truly - would own one. And we all know how effective Macrovision is for
stopping a pro pirate, so why in hell do the studios insist
on screwing things up for the consumer? The Extron
CVC200 may be vulnerable to Macrovision, but this very capable
and professional company stepped up to the plate. An exchange of e-mails quickly confirmed that it
is a known problem and that an upgrade was available. Better yet, since my transcoder was still under warranty,
the upgrade would be covered. Two weeks later, the modified transcoder had made
the round trip to California and was ready to be replaced
in my system. (While
it was away, I had switched the Denon into the interlaced
mode and resumed using my Faroudja Line Doubler; the Faroudja's
component video inputs are quite impervious to Macrovision's
nonsense.) I found
that the updated Extron did indeed pass stable video, but
alas, only for interlaced video; progressive video was still
modulated by the idiotic copy protection. I reported the results to Extron and it's currently
reproducing the problem using a Denon player in its West
Coast facility. I
anxiously await a solution, but I want to solve this problem
now.
Perusing a few forums pointed me to Key
Digital Systems, a manufacturer of specialized products
for home theater hobbyists and video game enthusiasts. Of
particular interest is its One Component to Two VGA Video
Adaptor, model KD-CTCA2. This very reasonably priced transcoder
accepts component video from a DVD player or from an HDTV
set top box in any of the three currently implemented formats
(480p, 720p, and 1080i) and transforms any of those signals
into the RGB-HV my projector craves. Manipulating a tiny
bank of dipswitches allows configuring the transcoder for
display compatibility, for automatic sensing of the input
video format, or may be set to a dedicated video format.
An exchange of e-mails with Key Digital indicated that the
video gain should remain constant in the presence of Macrovision,
so I acquired a unit.
When it
arrived, I was impressed by its tiny size. The transcoder is packaged in a small plastic housing
just big enough to hold the component video input jacks,
two VGA output connectors (you'll need a breakout cable
to connect the transcoder to your display), and a jack for
the external power supply that plugs directly into an outlet. I set Key Digital's dipswitches as described
in its manual for my application (negative sync, auto-format
detection, separate sync pulses), hooked it up, slipped
in the AVIA disc to do a cursory check of the waveforms
on my ïscope, and didn't recognize any problem. I then checked the waveforms with the Star
Wars Episode II: Attack of the Clones DVD and found
that the video gains on the RGB channels were stable; Macrovision
was gratefully ignored. With a sigh of relief, I substituted the Key
Digital for the Extron in my system, jumped to an AOTC chapter
at random and sat back, smiling in anticipation. Uh, oh. What's
that? Everything's too bright!
When I examined Key Digital's waveforms on my ïscope, I
noticed that the transcoder passed the sync pulses on the
three RGB signals (the Extron strips them out), but I assumed
that my projector would clamp on full black and ignore the
sync pulses. Nope. My projector, seeing horizontal and vertical
sync pulses at its HV inputs, processed the sync pulses
on the RGB lines as video and put the images up on a huge
brightness pedestal, so high that adjusting the projector's
brightness didn't help. I tried an alternative dipswitch
configuration (negative sync, 480p, separate sync pulses).
Same result. An e-mail to the very helpful Key Digital people
revealed that an undocumented dipswitch configuration (0000000xx
for negative sync, auto-format detection, sync on green)
would put the transcoder in the RGsB mode. I tried it. Eureka!
My projector recognized the RGsB signal, stripped the sync
pulses out of the RGB channels, and I had a stable, Macrovision-free
picture. I jumped to an AOTC chapter at random and
sat back, smiling in anticipation. Uh, oh. What's that?
White clouds are slightly pink. Everyone is sunburned. Everything's
too red! My color temperature is screwed up.
Out again came the ïscope and the AVIA DVD. I selected
the 100 IRE and 50 IRE (100% white level and 50% white level)
test patterns, found at Gray Scale & Levels / Gray Fields,
and checked the Key Digital's R, G, & B outputs. I found
that at 100 IRE, the red channel was 10% higher than the green
channel, and blue was 2.1% higher than green. (For RGB video,
green is 59% of the luminance, red is 30%, and blue is 11%,
so I use green as the reference.) For 50 IRE, red was 10.6%
too high, blue 3% too high. The three-color channels should
be the same amplitude for a pure white or pure gray video
signal. It's time for a short explanation; those wanting to
avoid the technobabble may skip the next paragraph.
Typically, a display's color temperature is set by adjusting the red, green,
and blue drives for high amplitude and low amplitude video.
A color analyzer would be used to ensure that over the full
video dynamic range, white is white, black is black, and
the grays in between are gray. No apparent tint should be
visible at any gray level; this is characteristic of the
desirable 6,500 degree Kelvin color temperature. I heartily
recommend an Imaging
Science Foundation (ISF) certified calibrator to
achieve these results on your display. Unless you have an
extraordinarily good eye and know exactly what you're doing,
making this adjustment on your own without instrumentation
could get you in deep trouble. If you insist on trying,
please write down the numerical settings for every adjustment
you plan to change before you begin. You must have
a way of returning to the original settings if you can't
get acceptable results! And be aware that some rear projector
manufacturers may void your warranty if factory authorized
service personnel detect that you accessed the service menu.
I spent
the next hour or so reworking my projector's six color temperature
settings and its brightness and contrast. I replaced the AVIA DVD with AOTC,
jumped to a chapter at random and sat back, wincing in anticipation. And smiled. The
video was highly detailed, the colors well balance, vivid,
and noise free. Fine details and revealing textures make it through the transcoder's
circuitry thanks to Key Digital's video frequency response,
-3 dB at 110 MHz, very impressive for a $350 list price
product. So when I later examined bandwidth on my ïscope
with an AVIA test pattern, I was not surprised when
I found no variation in frequency response when I compared
Key Digital's input to its output. Nor did the long coaxial cable runs to my projector
cause any drive problems for the transcoder's output buffers;
no visible ringing was imposed by the KD-CTCA2. Since the
transcoder's working configuration is an auto-format mode,
it was time to confirm the Key Digital's ability to handle
HDTV's broadcast standards. With the exception of WCBS, which had a backup
antenna and transmitter on the Empire State Building, I
haven't been able to receive HD transmissions from New York
since the barbaric attack of 9/11. (Fox and UPN share the CBS antenna, but since they
aren't transmitting in 720p or 1080i, they're certainly
not high definition.) Fortunately,
by rotating my antenna toward much farther away Philadelphia,
I can receive PBS in HD from Trenton and HD transmissions
from Philly's CBS, ABC, NBC, and WB affiliates. I'm pleased
to report that, with one unique exception, the Key Digital
performed flawlessly. Each
format locked in transparently and remained stable. The glorious 1080i resolution from CBS and PBS looked
as great as they did with the Extron. ABC's 720p looked lovely as well and the subtle resolution
differences when compared with 1080i were still apparent;
this indicates that the Key Digital's extended bandwidth
was more than adequate for the job of transcoding HD content. There was one small glitch that will be an issue only for some CRT-based
front projectors (CRT-based rear projectors that are capable
of high definition display modes are equipped with component
video inputs, so a transcoder is not required).
The NTSC video system, on which DVD is based, has bi-level
sync; each pulse extends below the image's full black level.
HD video signals have tri-level
sync pulses; they resemble two linked pulses of
opposite polarity similar to one cycle of a square wave.
HD's leading horizontal sync pulse is negative going, just
like NTSC's, but HD's trailing pulse is positive going,
and its amplitude pushes well up into the visible video's
amplitude range. When I tested the Key Digital transcoder
with HDTV signals, the positive going portion of HD's tri-level
sync was reproduced just like image data. The pulse was
located at the extreme edge of my projector's CRTs, beyond
the linear areas projected onto the screen by the projector's
lenses, so I didn't see the pulses as bright artifacts on
my screen. But, the pulses illuminated the phosphors at
the CRTs' edges so brightly that a lens flare was projected
onto my screen's right edge. During dark scenes or black
transitions, a gray streak was quite visible.
Attempts
to manipulate my projector's picture width and blanking
did not help. Apparently, those adjustments only work within
my projector's visible video data area, within the linear
portions of the tubes that are projected through the lenses. While this problem will not occur in fixed resolution projectors
(DLP, LCD, D-ILA), it may affect CRT front projectors besides
my own. Since this is a problem I cannot work around,
I decided to dedicate the Key Digital transcoder to my DVD
player and to dedicate the Extron Transcoder to my HDTV
set top box. I could then switch between the Extron's RGB-HV
and the Key Digital's RGsB signals with my existing high-bandwidth
Extron SW2ARHVxi switcher. Wrong
again. When I
connected through the switcher, the HDTV was great, just
as it had been for the last few years, but DVD content was
distorted. The right
edge of any bright to dark transition was contaminated by
a thin red outline, similar in appearance to misconvergence. At first, I thought there was some kind of
delay in the red channel that displaced red to the right,
but red was not absent at the opposite edge on the left. I then recalled that the Extron switcher, an electronic
device as opposed to an electromechanical device, had restricted
input specifications. Perhaps
the high amplitude I found on the red channel was overloading
the Extron's electronics and I was seeing a delay in recovering
from saturation. Once again, I investigated waveforms and made
a few quick amplitude measurements. At a video
amplitude of 100 IRE, the Extron transcoder produces about
670 mV at the red channel, 690 mV at the green, and 680
mV at the blue. For the same input (excluding offsets), the Key Digital produces
approximately 770 mV at the red channel, 710 mV at the green,
and 720 mV at the blue. Also, unlike the Extron, which was within a couple
of mV of zero for 0 IRE, the Key Digital had offsets of
about 960, 165, and 840 mV for R, G, & B respectively. And the Key digital passed the sync pulses, while the Extron transcoder
blanked them. I
consulted the input specifications for the Extron switcher
and found compatibility issues with the Key Digital's HD
signals. In all
fairness, I must point out that the offsets and sync pulses
are unlikely to affect your display; my projector provided
lovely pictures when I drove its RGB inputs directly. So I'm raising this issue only for any reader who
may own an Extron switcher similar to my own. For those
who may have an HD set top box that produces RGB-HV directly,
Key Digital offers another helpful product, a transcoder/switcher,
model KD-XB, called the XBlaster. This unit has one VGA output for RGB (the KD-CTCA2
has two outputs), one VGA input connector that accepts RGB-HV,
and a component video input that accepts 480p, 720p, and
1080i video formats. It
isn't as versatile as the KD-CTCA2, since it's intended
to transcode the component video output of an X-Box or GameCube
and to provide the means to use a computer's monitor for
game playing. For
example, it produces negative sync only, while the KD-CTCA2
produces negative and positive, switch selected; the Xblaster
has no switches. The
XBlaster will output either RGB-HV or RGsB automatically
based on the nature of the signal at its component video
inputs, and RGB-HV only from the VGA input connector. So it might be possible to connect a progressive
DVD player to the KD-XB's component video inputs, an RGB-HV
HD set top box to the KD-XB's RGB video inputs, and automatically
transcode and switch. (The
RGB input has first priority; transcoded component video
is outputted only in the presence of a signal at the component
video inputs.) Should you choose to try the Xblaster for this
type of application, you should communicate with Key Digital
about your specific equipment configuration to verify compatibility
before buying.
The Key Digital KD-CTCA2 transcoder - with three caveats
- can be a wonderful solution for the home theater enthusiast
who owns a display that requires RGB-HV or RGsB rather than
component video. For about a third of the cost of the Extron,
you'll have a solution. Follow Key Digital's instructions
first, applying the recommended switch configurations for
your source and display. Only if those all fail, and only
after you've confirmed your display's compatibility with
RGsB by consulting its user manual, should you try the undocumented
switch settings I mentioned. The downsides of the Key Digital
transcoder are that if you own a CRT-based projector, HDTV's
tri-level sync may cause a visible problem, you'll very
likely have to adjust your projector's color temperature,
and in the event that you own an electronic RGB switcher,
like the Extron, you may have signal level compatibility
issues.
The Interconnects
The Extron's input connectors are BNC and the Key Digital's
are RCA, so I needed a new component video cable for the
connection between my new player and my new transcoder.
I cannot stress enough the importance of proper cables for
your interconnects. Each video cable must have the appropriate
characteristic impedance - for video, 75 ohms - and appropriate
distributed reactance to avoid placing a destabilizing load
on the output devices driving the signal down the line.
Failing to provide these basic characteristics, a deficient
cable can cause ringing and smearing in the video. Too often,
cables are hyped like snake oil. Some cable companies, perhaps
to justify outrageous prices, make all kinds of fantastic
claims. I prefer cables that are well made with quality
materials and simply perform the task for which they are
intended: conveying the signal from one electronic device
to another without adversely affecting the quality or character
of the waveforms. For this deceptively simple task, I choose
the cables offered by BetterCables, reasonably priced, high-performance
interconnects that I've been using for years. For the new
connection between the Denon player and the Key Digital
transcoder, I needed a one-meter long component video cable
equipped with 75-ohm RCA connectors on each end. My choice
is the Silver Serpent.
(BetterCables also makes quality breakout cables, handy
for those who may have taken an interest in Key Digital's
transcoder.) Compared to conventional cables, BetterCables
provides higher bandwidth and is very well behaved. Subtle
details in the video become more apparent when compared
to conventional video cables. In other words, it's completely
transparent to the signal, just as it should be. Highly
recommended no matter what other equipment choices you make.
The Audio
The need for upgrading here was clear, and finding the
right solutions was much easier than for my video chain.
In my Pseudo-EX
piece, I described how it was possible to reconfigure an
existing Dolby Digital 5.1 system to perform 6.1 decoding
by adding a Dolby Surround decoder to a digital audio decoder's
analog surround outputs. My trusty old Shure HTS-5300 analog
Dolby Surround decoder worked very well with my B&K
AVP-3090 digital decoder/preamp, but three issues remained
unresolved. I could not adjust independently the time delay
to the center surround speaker. If the delays aren't right,
imaging suffers and the audible locations of sound sources
in the surround channels become vague and sloppy. That problem's
easy to resolve, virtually all respectable 6.1 decoders
or receivers permit an independent delay setting for each
loudspeaker. An inconvenience was the 3090's inability to
automatically detect DTS; that, too, was easy to resolve
since any DTS-capable replacement will switch automatically
as it recognizes the incoming audio bit stream. And the
AVP-3090 did not offer THX re-equalization; correcting that
deficiency required a little more selectivity.
In my review of Blade II, I mentioned one of DVD's
dirty little secrets: The X-Curve. Allow me to quote myself,
ñFor reasons too involved to describe in detail here (but
associated with theater electronics and the acoustics of
a large room, as opposed to the acoustics of the typical
small space found in a home theater), film soundtracks are
pre-emphasized. Frequencies above 2 KHz are rolled up at
3 dB per octave (or better put, 1 dB per third-octave as
measured with pink noise and a third-octave analyzer). When
the soundtrack is played back at home, to restore a ïflat
response' and remove the unnatural brightness, the high
frequencies are rolled off at -3 dB per octave from 2 KHz
upward. For those of you who own THX certified decoders
or digital receivers, that's what THX re-equalization does.
DVD's are usually shipped with the pre-emphasis intact,
requiring de-emphasis to restore tonal balance, so without
equipment capable of THX re-equalization, you may be at
a disadvantage. ...there is one DVD audio production house
that removes the pre-emphasis as the audio is transferred
to the disc: Mi Casa Multimedia. They may be out there,
but I'm unaware of other audio subcontractors that re-equalize
the audio prior to compression and authoring.î Learning
in advance which DVDs have the X-Curve removed is a challenge.
Recently, that information has been included on some New
Line DVDs' audio set up screens. A helpful list of de-emphasized
titles may be found at this Mi Casa
Multimedia link.
When you listen to film audio at home in which the pre-emphasis
is intact on the DVD and without X-Curve de-emphasis (THX
re-equalization) applied by your decoder, the sound will
be too hot - too much high frequency content. If you listen
to a Mi Casa de-emphasized DVD with THX re-equalization
enabled, the sound will be too dull - too little high frequency
content. The decoder mode must be matched to the way the
DVD's audio was produced: pre-emphasis removed, apply the
flat mode; pre-emphasis intact, apply the THX re-equalization
mode. To ensure that I'd have that level of control, I was
predisposed to purchase a THX-certified decoder, the decoders
that offer THX re-equalization. I've always been rather
partial to B&K
Components. The company makes a fine product at
an outstanding price/performance ratio and supports its
customer base with updates should they become necessary.
I chose the B&K Reference 30 THX Ultra preamp/decoder.
As for the other electronics, I didn't have to purchase
anything else; on hand were a beefy power amplifier from
a German company for which I had provided engineering consulting
services a number of years ago, and a parametric equalizer
prototype I had designed. For the loudspeaker, I had been
using an M&K
S-100B for my EX center surround ever since I put the Pseudo-EX
configuration in place; it was chosen for its timbre-match
to the other M&K loudspeakers in my system. It's rather
important that the audible characteristics of all of a system's
speakers be very, very similar. Otherwise, as a sound travels
around the room (like during a 360 degree pan), the timbre
will change; if the sound's character varies depending on
its location, it will draw attention to itself and possibly
distract the viewer to the point of collapsing a willing
suspension of disbelief. And differences in frequency response
may also destroy accurate spatial imaging. So the S-100B
remains.
Parting
Thoughts
Improving the video chain was a little painful, but the results
are wonderful. My presentation is closer to film than I was
able to achieve before. I'm looking forward to resolving my
remaining RGB video switch issue; I'm sure that will happen
within a month or so. I'll report back with an addendum when
I finally have the total solution in place. Less recent was
the audio upgrade; it's actually about two years old. That
upgrade was painless to implement and proved to be very satisfying,
providing a noticeable improvement in sonic accuracy.
I know there's a lot to consider here. Buying home theater
equipment should be much easier (and testing publications
should be a lot more informative). I'm looking forward to
the day when capable audio and video equipment become pure
plug-and-play. Until then, you almost have to hold an engineering
degree to get it done right. Once again, I hope you find
some of the lessons I learned while going through my upgrade
helpful. The best of luck with yours.
Postscript
During the delay between my submission of this sixth installment
of "Mr. Blandings Build His Dream Theater" and
its publication, Extron completed its investigation of my
CVC200 transcoder's Macrovision problem and devised a solution.
My transcoder was returned to me, and it no longer pumps
the video gain for Macrovision protected DVDs; once again,
it produces splendid images. At a higher price, the Extron's
output is free of sync pulses and offsets, and maintains
color temperature with much greater accuracy than the Key
Digital. It was only necessary to boost my projector's green
drives by about 4% to achieve proper color temperature with
the CVC200 (nothing's perfect). It's my understanding that
the changes made to my Extron transcoder have been passed
along to manufacturing and all future production units will
be insensitive to Macrovision. And now I'll also be watching
with great interest to see if Key Digital corrects the problems
I uncovered during my upgrade adventure as they introduce
future products.
(If you have any questions or comments for the author,
say hello to Dan here.)
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