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Q I'm looking into purchasing a DVD player, but I'm concerned about which players will play which formats. My understanding is that movies on DVD have Pro Logic / Dolby Digital audio encoding, with DTS encoding being pushed back until November, 1998 or so. For pure music, there are CDs / DVDs encoded PL, DD, DTS, and coming soon a new DVD audio format which rumor has will be Meridian's MLP.
Optimally, I'd like to purchase a player
that can play any disc with any format, with hopes that as new
formats come about the upgrade path
isn't "buy a new player." I suspect that isn't the case
yet, so what's the best I can do in the near term? I've heard
the Panasonic A310 will handle
DD and looks for the DTS flag and passes the raw DTS info to a
DTS decoder, but this means that it won't handle the DVD audio
format whatsoever. Or would you expect the Sony 7700 to be able
to handle everything? Or is it just too early to tell at this
point?
A The new DVD players will output everything except the Meridian Lossless Packing (MLP) data. That format it too new to say much about. However, all of Merdian's processors are now being shipped with MLP capability, and Meridian makes a point of upgradability in their products. The DVD audio format right now is called Digitial Audio Disc (DAD), one type of which is PCM encoded 96 kHz - 24 bit, two channel stereo. It is the next step up from 44.1 kHz - 16 bit CDs, and is different than 5.1 channel DD or DTS music DVDs (there are also some CDs with DTS music on them.) We are testing a 96/24 DAD sampler disc (Chesky) with a Yamaha DVD-S700 DVD player now (it sounds great!), and I have seen several DADs being advertised in audio magazines recently. In the case of DD and DTS, the new players with DTS capability specify this as "DTS Digital Out", either on the front of the player or in the instruction manual that comes with it. I think all the players as of 1999 will be DTS compatible. We should have a DTS DVD in a week or so to test the Yamaha player.
Q I
primarily watch the tube for cable broadcast but do enjoy movies
1-2 times each week. The simplicity of video tape as well as the
variety of material has made it the media of choice up to now
for me. In the past I have liked the picture of laserdiscs but
have been disillusioned with
their formatting in 16:9 to fit my 35" Proscan's tube. The
black bars are too distracting and the remaining image is too
small for my tastes.
The DVD format market seems to be solidifying enough to get me interested in a 16:9 TV, but what happens when I watch "regular" programming? Would one find the 4:3 picture a distraction? Does a 42" HDTV become a 17" regular TV when this occurs? It seems that it will be decades before regular broadcasts will be 16:9 and spending several thousand of dineros on a white elephant ain't my cup of tea! I enjoy regular tube shows too much.
Can you help clarify these issues for me and the rest of potential videophiles out there.
A When
DVDs first came out, the widescreen version was on one side, and
the 4:3 version was on the other. Lately, most DVD movies seem
only to have the widescreen version, so the black bars at the
top and bottom of 4:3 TVs are unavoidable. By the way, for those
of you who are confused about the settings on the DVD player menu,
if you have a 4:3 TV, then set the menu for pan and scan or 4:3,
regardless of the movie. It's only if you have a 16:9 TV that
you should use the 16:9 setting on the DVD player menu. When HDTVs
arrive, they will all be 16:9. "Regular" old style programming
will be 4:3, and if you want to see all of the 4:3 image, you
will have to put up with black bars on the sides instead of the
top and bottom, and your $10,000 60" HDTV will be like a
smaller NTSC TV. If you have a DVD player, you will need to reset
it for 16:9 for use with HDTVs. Otherwise, you would end up with
a miniature widescreen image inside the 4:3 NTSC box, with black
bars on the sides. Our local cable company just sent me literature
offering me a digital TV connection, so they are getting ready
for HDTV. The extra $10/month fee includes a digital-to-analog
converter so I can watch these digital programs on my analog TV.
If I can get a cable modem for use with the Internet, I will get
the digital connection now. Otherwise, since the digital programming
isn't much different right now than what I get with regular cable,
I plan to wait until I have an HDTV before getting the digital
TV connection. I think that in a few years, we will all have a
miniature satellite dish or cable connection that will give us
digital TV, high speed Internet (1 Megabit/second) access, and
digital telephone service. It means that no matter where you live,
you could have all these things without the need for telephone
wires leading to your house. For those of you with homes in wilderness
areas, it's really good news.
Q If tube gear has more distortion than solid state gear, why do many audiophiles prefer the tube sound over solid state? I hear terms such as "more natural", "liquidy midrange", "smoother and rounded sound" as their "alibis" for liking its sound. What's your stand on this?
If ever I go with tubes (succumbing to pressure
from audiophile friends), is it advisable to attach a fan (just
like those in computer CPUs) to cool them off?
A Tubes
do have somewhat more distortion than transistors, but tubes tend
to produce even-ordered harmonics rather than odd-ordered harmonics.
Even-ordered harmonics are pleasant to hear, sort of like the
harmony parts in a barber shop quartet. Particularly with single-ended
triode designs, there is no need for negative feedback, so specs
like 2% harmonic distortion are common. With push-pull designs,
negative feedback is usually employed, and this increases the
odd-ordered harmonic distortion, although the figure for total
harmonic distortion goes down, to, say, 0.5%. The even-ordered
harmonics add body to the music. It's an artificial addition,
but because it's pleasant, tubeophiles enjoy it. Most of the distortion
is in the midrange, so that accounts for the adjective. They also
tend not to have quite the high frequency response that solid
state components have, and this can lend a nice effect when harsh
CDs are played. In any case, do not get them just because your
friends say tubes are great. Go and listen to them for yourself.
Modern tube designs take into account the need for cooling, so
if they don't come with a fan, there is no need for you to add
one. Just make sure the component has adequate ventilation above
it, in front, and behind. Don't place it on a rug, since air flow
comes from beneath.
Q Do
coaxial digital lines send 5.1 channels or just 2 channels? My
Yamaha receiver has one optical line and 2 coaxial lines. In the
manual
it seems like they refer to the coaxial digital lines as being
2 channel and the optical lines are 5.1. Also, is there a DSS
system with coaxial
digital outs?
A Coax
and Optical digital cables send the same information, but they
use different methods to transmit the data. I am not aware of
any DSS systems that are using coax. The Sony has an optical digital
output. MSB Technology can add a coax digital output to an existing
DSS receiver.
Q I've
moved up to AC-3 from Pro Logic and am considering a change to
my surrounds. I'm presently using Atlantic Tech dipole surrounds
mounted to the side of my listening position. I'm considering
going to four direct radiating surround speakers. Two mounted
high (6') to the sides of the listening position firing straight
across. The other two mounted high on the rear wall (2' from corners)
would be pointing forward into the listening area (the surround
speakers I'm considering are an exact match to my mains and center).
I feel that this would best simulate the multiple speaker arrays
found in theaters. Has this been tried in any of your setups?
If not could you shed some light on the idea and your opinion?
A The
reason multiple surrounds are used in commercial theaters is that
the theater is very large to hold hundreds of people. At home,
you only need one set of rear surrounds because the room is much
smaller. The idea is not so much to reproduce the situation at
a commercial theater, but to reproduce the sound that the director
intended. With DD and DTS, you will be much better off using the
surround speakers that are matches to your fronts, as you said,
but use only one pair, not two. Otherwise, your rear surround
sound could overpower the front sound.
Q I
live in a condo with a concrete foundation and would like to build
a room to house our home theatre system. I have a dwelling on
either side. I have the flexibility with the room dimensions,
but would like to be able to use the system at moderately high
volume once in a while. Any thoughts or experience would be appreciated.
A I
found that using fiberglass insulation in the walls, floor, and
ceiling works very well. Assuming you plan to have access to the
exposed internal parts of the wall, put in a layer of fiberglass
between all the studs in all four walls. Put a layer in the attic
above the ceiling too. Use a thick carpet on the floor. By insulating
all walls, ceiling, and floor, you will contain the sound, and
it will be less likely to transmit to walls that are common with
your neighbors. While you have the walls exposed, don't forget
to put in the speaker cables that you need for the rear speakers,
and some extra AC wall outlets.
Q I
purchased a digital sound level meter in order to measure the
volume coming out of each of the channels when the test tone generator
of the receiver is used. What would be the difference between
the A-weighted and C-weighted scales? What would be the correct
procedure to measure the volume, given that I would have a reference
distance (equidistant?) to each of the speakers so as not to distort
the measurement?
A The
weighting refers to the frequency response of the meter. With
A-weighting, the meter responds mainly in the 500 Hz - 10 kHz
range, while with C-weighting, it responds mainly to 32 Hz - 10
kHz. I use C-weighting with my meter.
Q The
Yamaha DSP-A1 and 2092 both indicate that they're able to handle
2 center speakers but there is a switch on the back because they
are wired in series. What does that mean? Does it mean only 1
center speaker at a time?
A There
are two ways to wire two speakers to one channel. 
One method is in series and the other is in
parallel. When you do it in series, the impedance that the amplifier
sees is doubled (assuming both speakers have the same individual
impedance, such as 8 Ohms). So, in the case of two 8 Ohm speakers,
the resulting impedance would be 16 Ohms. When you do it in parallel,
the impedance is cut in half, e.g., two 8 Ohm speakers would result
in a 4 Ohm impedance to the amplifier. Receiver amplifiers are
not really designed for low impedances, so that is why the switch
is there. It puts the speaker binding posts for the two speakers
in the center channel in series. The diagram on the left shows
how this would be done if the switch were not present. Both speakers
will function, but the impedance will be higher rather than lower,
and this is easier on the amplifier. With high performance amplifiers
that have a substantial power supply, you can often connect two
speakers in parallel without any problems.