Q What is your recommended choice of connections between coax inputs and optical inputs for DVD and LD? I have heard a few negative remarks on optical connections - limited bandwidth and loss of signal if coiled too tight to name a few.

Also, isn't it true that AC-3 (DD) LD players should not be connected to optical or coax cables because these cannot transmit the analog AC-3 signal? It seems LD players must use the RF connection to get the AC-3 signal. However, aren't DVDs another story entirely? In the DVD format, all of the digital outs seemingly transmit DD. If this is the case, which type of connection gives the best overall sound and picture - optical or coax?

A The whole connector thing is very confusing. Whenever I go to Fry's Electronics looking for an adapter so I can use connector "X" with jack "Y", I have to keep telling myself, "Stay calm. It's here somewhere". Sometimes I think my dad is right. All he wants is "On", "Off", and the Volume Control. The advantages of optical cable are the lack of a ground loop problem, lack of impedance matching problems, and the lack of capacitance-inductance problems. Personally, I have not been able to tell a difference between optical and coaxial connections. However, as you say, the general opinion is that coaxial is preferable. If you have a DVD player and an LD player, it may be necessary to use optical for one player and coaxial for the other, depending on the jacks that are available. This is what I do with my system, and it works fine. If there is a ground loop problem, optical cable can help reduce it. For DD from an LD player, you have to use a coaxial cable because an RCA jack is all that's available for the RF output. The other digital coax output or optical output on the LD player transmits only the bitstream from the PCM digital audio tracks. No video signal comes through the optical output. Just the audio. DVD players have coaxial and/or optical digital outputs too, and they transmit the DD bitstream to the decoder. So, with a DVD player and an LD player, you could use the LD coaxial RF output to the RF input on the decoder/receiver, and the optical output from the DVD player to the DD digital input on the decoder/receiver. You need to make sure you don't mix up the coaxial analog audio inputs/outputs with the coaxial digital inputs/outputs. With so many connections, it is easy to make this mistake, so when first connecting a new component into your system, keep the volume down very low to start.

Q While seeing a demonstration of the Yamaha DSP A1 Surround Sound Processor/Amplifier at a local dealership, I noticed the salesman was using a DTS demo disc on a non DTS DVD player. Yet the A1 was still decoding in the DTS mode. When I pointed it out to him, he did not know why. He then connected two other non DTS DVD players, and the A1 unit played those in the DTS mode also. My question is if I purchase the Yamaha A1, can I use a non DTS DVD player and still get all the benefits of the DTS format?

A The DTS demo disc has the DTS in PCM format. This disc will play on all DVD players. When DVD movies are released in the final format (supposed to be this month), they will not be in PCM, but rather, a different format. Only the newer DVD players that say DTS Digital Output, or some other means of letting you know they are DTS compatible, will be able to play these discs. By play, I mean the player will be able to recognize that the disc is DTS, and output the DTS bitstream through a jack on the rear of the player. Then, you connect this jack to the digital input jack on the processor or receiver that has DTS decoding capability. The Yamaha DSP A1 has DTS decoding built-in, and should be able to decode the DTS from the DVD. However, we won't know if everything works the way they say it is supposed to until we have a DTS compatible DVD player, which should be shortly.

Q Please explain DUAL LAYER DVDs. Yes or No, If a DVD runs over 133 minutes do I flip it? Is there a pause like on laser until it reads the other side, or if the movie is say 3 hours long does it play non-stop, pause-free with no visual or audio interruption?

A The first DVDs last year were dual sided, but not dual layer. That meant you had to flip the disc if the movie was longer than two hours or so, depending on the amount of compression. If the maximum amount of compression is used, 133 minutes per layer, per side, are available. All of the new discs that I have rented are dual layer. This is called RSDL, or Reverse Spiral, Dual Layer. The first layer is read from the center of the disc out to the perimeter, in a spiral. Then the laser lens refocuses to read the deeper layer, which spirals from the outer perimeter back to the center of the disc (the spiral is reversed, so that the disc can continue to spin in the same direction, but the lens follows the spiral back to the center of the disc). Sometimes I can tell when the lens goes to the second layer, and other times, I have not noticed it. Even when it is noticeable, it is a very short delay of one second or less. With the advent of RSDL discs, we can watch even the longest movies (e.g., "Spartacus") without having to turn the disc over. Also, I saw one disc that had the widescreen version on one layer, and the pan & scan version on the second layer, all on one side of the disc. However, most films seem to be released now with just the widescreen version and dual layer, and no pan & scan version. I did see one disc with the movie on one side, and a featurette on the other. All DVD players, including the first ones sold last year, can play RSDL.

Q I am one of those dunderheads who purchased a first generation DVD player. Now I am seeing ones with DTS stamped on them. Also, I think mine offers 8 bit video, and am now seeing 10.

Is DTS really a better format, and will one be able to tell a marked difference between it and DD? Also, what about the difference between 8
and 10 bit?

It seems impossible to keep up with all the new technology changes these days. I also purchased an Sony ESP-800 Decoder, and then noticed that several had been returned to the store. No one would say why. Am I missing something? Is this not a good decoder? Do you know anything about it?

Last question is, I also purchased a Sony "Digital Ready Receiver". Will I have to start all over with new everything for DTS?

A Don't beat yourself up for being an "Early Adopter". It is an important group that drives the industry. Yes, we will have to get new players, but we have been enjoying DVD movies for a year. Ten bit video will have more dynamic range in the picture than 8 bit video. It does not affect the audio. Twenty four bit audio will have more dynamic range than 16 bit. It's the same principle. I don't know why some of the Sony decoders were being returned. It could be a problem that affected some units and not others. If yours is operating fine, don't worry about it. Your "Digital Ready Receiver" has a set of 5.1 input jacks on the rear for connecting an outboard decoder. You can use a separate DD decoder and DTS decoder, since they have pass through jacks for two decoders, or you can use a combined DD/DTS decoder. When it says, "Digital Ready", this means that it has the set of input jacks rather than decoding built-in.

Speaking of DVD players, we have yet another change coming this Fall. There have been some new DVD players announced that will play the discs in progressive scan format. This means that all 480 lines (NTSC TVs call it 525, but actually only 480 are visible) of each frame will be displayed at the same time, rather than interlaced where half the lines are displayed in one field and then the second half of the lines in the next field. These players are being released for Digital Televisions (DTV) which are also going to be sold starting in the Fall. The image from these DVD players on the DTVs will be much better than from the current DVD players on our current NTSC interlaced TVs for several reasons. One is that the signal will be processed by the TV digitally without having to go through conversion to analog. Secondly, the scanning lines of the image will be less noticeable. It will be like a line doubler image, except that all the lines will be actual data rather than computer generated. The good news is that all of our DVD software (movies) are already in the progressive scan format. Current players output the data in the interlaced format since our NTSC TVs will only handle that kind of signal. So, if you get the new player and a DTV, all of your DVD movie collection (and all of the DVD movies for rental that are in the video stores now) will play in progressive scan format.

As to which of the digital formats - DD and DTS - is superior to the other, it has been difficult to really tell so far, since DD is in the right analog channel and DTS is in the digital channels of laserdiscs. Plus, DTS tracks have tended to be somewhat louder than DD tracks. I think when DTS DVDs are released, we may be able to get a better handle on this question. However, even if one is obviously better than the other, it is not a situation of winner take all and the other disappears. We are likely to have both formats for quite some time, and most receivers after the beginning of 1999 will likely have both format decoding capability built-in. I think this will be a matter of just getting the movie and enjoying it in whatever format it is available in, because there is no choice. If we were to see all DVD movies available in both formats, then it would be worthwhile to do in depth analyses, but that is not going to happen.

Q First, I must thank you for the advice I have received from the staff at SHT&HF. It has been very helpful in upgrading my HT system. I have
replaced my subwoofer with a Sunfire MKII. Also, I added a Sunfire Cinema Grand to my Sherwood R945 receiver. What great advice! Now, I'd like to upgrade my speakers. Currently I have an older Klipsch HT set (about $1,200 - 4 years ago). I'm planning on spending $2,000-3,000 for the new ones. My questions are: 1. Is $2,000-3,000 enough for some good sound? 2. You advised getting five of the exact same speakers for Dolby Digital. However, the THX web site offered some confusing information. What do you think? see below:

"Will Home THX Dipole Surrounds work with these 5.1 channel digital formats?

Yes. The Dipole Surrounds' design emulates the soundfield of an array of loudspeakers exactly as those found in mixing theatres and movie theatres. In movie theatres, these "surround arrays" provide a big surround sound experience. Because surround placement in the home is limited to a few speakers close to the listener, the THX Dipole Surround is the best way to provide a big surround experience. Sound effects and pans will have correct directional cues, and surround ambiences will be open and enveloping. With the newer "split surround" formats it is even more important that surround cues and pans do not "collapse into a box"."

Lastly, which speakers do you recommend in my range?

A For Pro Logic, dipoles work very well. However, with digital surround (DD and DTS), the sound in the rear is very specific and focussed, sometimes too much so in fact. I like dipoles, but some consumers do not. What I have found is that digital surround works best (for me) with the same speakers in the rear as in the front. For my listening room, this means direct (monopoles), floorstanding speakers, not dipoles or bipoles. Because of the way my room is set up, I can't easily use dipoles in the rear. But even if it were simple, using dipoles in the rear and direct speakers in the front would mean a different sound quality between the front and rear. For a smooth transition of sound effects that move from front to back or back to front (like a jet flying overhead), having all the speakers the same is best (in my opinion). Of course, in most circumstances, the center channel speaker has to be different than the others, but having those other four speakers identical really helps. The soundstage will enlarge with dipoles, but it would probably be best to have dipoles in the front and rear, rather than just the rear. Digital surround sound has complicated the whole situation of choosing speakers, but it is really a matter of sound preferences, budget, and layout of the room. Certainly, $2,000 - $3,000 will get you some very fine speakers. For mini-monitor size, the B&W 602s are great. Excellent floorstanding speakers in your price range include the NHT 2.5i and Platinum Audio Studio 3.

Q I have a Denon 3200 receiver with 5 NHT Superzeroes and a NHT SA1 amplifier connected in parallel to 2 NHT SW1 subwoofers. My question is how do I adjust the subwoofer in DPL vs DD. The 3200 has a speaker balancing mode which can be used to adjust all speakers including the subwoofer in DPL using an internal test tone. The 3200 also has LFE adjustment which you can back off the subwoofer for DD.

Using a SPL meter, I have to set the subwoofer to -8 using the internal test tones of the 3200 for DPL. Do I have to also set the LFE adjustment on the receiver to -8dB using a DVD test disc like Video Essentials or does the DPL setting of -8dB also affect the LFE setting as well? I had read in another magazine a while back the setting the subwoofer in DPL would also set it for DD. However, if this is so then why is there a LFE adjustment on the 3200? I had a difficult time telling if there was an interaction between these settings while I was playing a DVD source. This is very confusing


A As I understand it, there's an adjustment for the subwoofer output itself, but the LFE channel is not necessarily a subwoofer channel, since you could theoretically route it to the main speakers in the 3200's setup menu if you don't have a subwoofer, or even send the bass to both the main and subwoofer channels. The LFE channel adjustment lets you choose how much of the BOOM you want when you get your CRASH, BOOM, BANG, without simply turning up the bass which would also affect voices and such. Whether the LFE channel is actually used this way, or is just a monaural mix of the bass content of the other five channels, depends on the movie.

I would suggest that you set your subwoofer level for how you like it with DPL, and then adjust your LFE channel to taste using some AC-3 material, leaving the subwoofer level where it is. The LFE channel adjustment can be a neat feature, since if you've set the subwoofer level and crossover to blend with fuller-range speakers, you can leave it alone.

Q I recently finished installing my home theater system. It's composed of Jamo THX One, Onkyo TX-DS939A/V, Onkyo M504 Amplifier, and Pioneer DVD player. The system parameters of the Onkyo are confusing, and the analyzer setup doesn't satisfy me. How do I tune this system? Do I stick with the analyzer settings or do I manually set them to my liking?

A The analyzer is just a starting point. After that, fine tune the system to your personal preferences. SPL meters are useful for finding out if one speaker is louder than the other because it is near a wall, or finding bumps and dips at various frequencies that you can adjust with an equalizer, but after that, your own tastes always take priority.

Q I am planning to upgrade to DD & DVD and have 2 questions if you please --

Current system includes:
Sony TA-E1000ESD preamp/Dolby Pro Logic
(2) Rotel RB-850 power amp (subwoofer & surround-both are mono-blocked)
Parasound HCA-800II (Left/Right)
Adcom GFA-535 (center channel-monoblock)
Velodyne VA 1012
Philips CDV487 (laserdisc/CD)
Sony 32XBR-10

(1) What are the pros and cons of buying an LD/DVD combo player vs. just a DVD player to add to my system?

(2) What are the pros and cons of adding an outboard DD processor vs. buying a receiver with built-in DD and using my current amps? (I guess I'll need to buy 2 more power amps so I can use all in monoblock mode.)

A Laserdiscs seem to be going the way of the Dodo long before anyone thought. The local video store where I rent says that in the last month, DVD rentals have finally surpassed laserdisc rentals. They get about 10 new DVDs each week, compared to just 5 laserdiscs. One national chain says they will not be purchasing any laserdiscs for sale after the end of 1998. However, there is a tremendous library of laserdiscs out there if you have access to a video store that has the library and rents them. Since you already have a laserdisc player, I would suggest getting a dedicated DVD player, and one that has DTS capability.

There are three main advantages of having digital surround decoding built-in rather than as outboard. One is convenience. You only have to power up one box. Secondly, the DSP soundfields of the receiver will usually apply to digital surround too, since digital surround is part of the receiver's circuitry. Third, there will be less hum and noise with the one box solution, since interconnects have to be used with outboard processors, and there is always the chance of having a ground loop. The disadvantages of one box solutions are that they will be less flexible in terms of adding new technologies, and the built-in power amplifiers are usually not on a par with outboard power amplifiers. During the last year or so, we have been very pro on the outboard option. However, now that DD and DTS will be standard features of new receivers towards the end of this year and beginning of 1999, plus the fact that some of the manufacturers are finally getting the message about our desire for massive power built-in, I think we are going to find some one box components that are really excellent.

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