Q&A # 115 - May 11, 1999

Staff

Q I live in the UK and have the following setup: Denon AVR 3200, Pioneer 925 laserdisc player (via a DACman for CD playing), Panasonic 110A (region 1) DVD player, B&W CDM C SE centre speaker, B&W 804 (FL/FR), B&W DS6, REL Storm, and various Cable Talk interconnects and Monster speaker cable. I am in general happy with the setup but always striving for perfection! My goal would be something like a Meridian 861 and Parasound 1205 power amp, but at present, the expense is prohibitive. However, I do have the opportunity to buy a Rotel RB 985 THX 5 channel amp. Will I notice an improvement if I attach this to my Denon and will it be a useful stop gap until I buy the Meridian and then upgrade to the Parasound later (spreads the cost out over a longer period)? I feel that the sound, although good, is not as crisp as I have experienced when I was into music only.

A Yes, the Rotel RB-985 is a very nice product for the $1,000 US that it costs. It will provide improvement with all receivers in the 85 watt per channel category, such as the Denon AVR-3200, but keep in mind that the 3200 has pre-outs only for the front left, center, and right. The other two channels of the RB-985 could be used to drive a pair of stereo speakers in another room if you like. With the new crop of high-performance receivers, such as the Denon AVR-5700, however, it would take something like the Sunfire or Cinepro five channel power amplifiers to make a difference. The on-board power amps in these new receivers are quite good.

Q It is my understanding that there will be D/A converters for non-digital TVs as Digital TV broadcasts become more common. These should improve your picture quality by displaying ~450 lines of resolution to your analog TV. But, It is my understanding that newer analog TVs today can display 800 lines or more of resolution. Using DVD or S-Video inputs, will there be D/A converters capable of converting HDTV signals (=>720 lines) to 800 lines on your analog TV?

A Theoretically, this would be possible, but it will all depend on the bandwidth capability of the circuitry in the analog TV. It costs more money to build the TV to handle high bandwidth signals, and there is no particular reason to make the TV with high bandwidth capability when analog broadcasts, laserdisc, and DVD go no higher than about 6 MHz. However, I would think that HDTV signals decoded to analog for conventional TVs will probably deliver a signal that approaches 600 lines of horizontal resolution.

Q I am stationed in Europe with the government and want to buy a DVD player. Questions: Are players multistandard? I know voltage can be overcome with a transformer, but will cycles be a problem? If players are not multistandard, does this mean that if I buy a DVD movie here in Europe it won't work on a player that I buy in the states? Basically I know nothing about this and would like to know more before launching myself into it. I have asked in stores over here but I can't say that I am convinced about what to do. I get the feeling they just want to sell.

A The discs are standardized, but they have regional codes that prevent them from being played on machines from different countries with different regional codes. However, for the United States, you would need a DVD player that outputs NTSC signals that can be used by NTSC TVs. Parts of Europe use the PAL system and 625 scanning lines, so the players in those countries are designed to output PAL signals from the discs to go to the TVs. Depending on how long you will be in Europe, it may be best just to purchase a DVD player for the European country where you are, then sell it to a friend when you move back to the States and get an NTSC DVD player at that time. You have to consider what you will do with the discs that you buy over there too. They won't play on USA DVD players. My suggestion would be to just rent discs over there and wait until you get back home before you start purchasing a DVD collection. If some of our readers have DVD player/DVD software experiences with moving between countries in Europe, Asia, and North/South America, e-mail the editor and let us know what you did.

Q Recently I purchased Toshiba DVD player, and I've rented appoximately ten movies. To my surprise, all of them except two are only in letterbox. This really ticks me off as I hate letterbox movies (I just purchased a new SONY 53" R.P.V-75). Why are the motion picture companies doing this when most people have a 4:3 TV?

A The letterbox vs. Pan & Scan issue is very controversial. Indeed, it appears that most folks do not like the letterbox presentations, even though letterbox is the standard in commercial movie theaters (for example, I like them, but my wife and daughter do not). Studies indicate that if the blank areas at the top and bottom are masked off, viewers are happier with the letterboxed images. To me, the problem stems from the 4:3 full screen images and the letterbox images (16:9 and 2.35:1) are shown at the same width on a 4:3 TV, when the letterbox images are really designed to be shown at a wider size. Once 16:9 TVs are the norm, which will be the case in the next few years as DTVs, including HDTV, become more common in homes, we will have a situation where the 4:3 images occupy the center portion of the TV screen, while the widescreen (letterbox) images will occupy the entire screen. At that point, everyone will probably prefer the letterbox images. The first DVDs all seemed to have the letterbox version of movies on one side of the disc and P&S versions on the other side. Now, DVDs mostly are just in letterbox. Since you don't really have a choice, my suggestion is to try and mask off the top and bottom of the TV with curtain material (like you would expect in a theater) so that the blank picture tube areas are not exposed. Also, sit a little closer when viewing letterboxed movies so that, perceptually, the image appears larger side to side than when you view full screen images.

Q Recently a few DSS receivers have been coming to market with digital outputs (mostly Toslink) to pass along the DD bitstream from the pay per view movie channels. I was wondering if if these outputs were active for normal programming material as well so that standard audio for all channels could be output in a PCM format. I ask this because my processor is digital (DC-1) and think there would be a significant sonic benefit to a direct connection to avoid unecessary D/A conversion in the satellite receiver and A/D conversion in my processor.

A The DD output jack transmits the DD bitstream and compressed 48 kHz audio on the other channels, so you should be able to decode the audio on all the channels if you have a processor with DD decoding and standard PCM decoding. I agree it would be great to have one digital output for all the audio and let the digital decoders in our receivers handle the signal whether it is DD, DTS, or two-channel non-compressed PCM. Part (most?) of the problem is the studios' obsession with copy protection. Remember that there are lots of digital music channels available by satellite and cable. The copyright issue is also why the 24/96 capabilities of DVD players are limited in most players to outputting only the decoded analog audio or a digital biststream downconverted to 16/48. I understand there was some discussion of future DVD players only outputting the 5.1 analog decoded DD and eliminating the digital output jack, but that never materialized. There isn't any real reason why they couldn't output non-compressed digital audio from that one DSS jack, but paranoia is going to prevent it from happening for a while. From the viewpoint of producers, however, one can understand why they are concerned, since billions of dollars are at stake.

Q I recently got a DSS system, the Sony SAS-AD4, which is capable of handling Dolby Digital. Today, I started to watch "Out of Sight" on PPV in letterbox and DD 5.1, when I noticed that the sound was slightly out of sync. I don't have this problem on any other channel. I checked DirecTV channel 500, which shows Dolby Digital previews and demos, and did not notice any problems with the DD signal on that channel. I assumed that the problem was with the transmission, so I called DirecTV, but they told me that everything was fine on their end, so they recommended I call Sony. I did, but though they were nice and helpful, they couldn't explain why this happened. I also have a Sony S7000 DVD player, and everything is hooked up to a Yamaha RX-V992 receiver, and I've never had any sound sync problems with any other source. I still think the problem is caused by DirecTV, and I'm wondering if this is a common problem. Have you heard about this problem before?

A This occurs when the video processing results in the picture being shown a littler later than it otherwise would. This throws it out of sync with the sound. If it is happening on that one channel and not the others, I think you are right in assuming it originates at the broadcast. DirecTV and cable TV services don't necessarily process any of the channel signals. They just collect them from the broadcasters and pass them through to the consumers on whatever channel frequency they want. The broadcaster of that channel may be experimenting with video processing or downconverting from HDTV. This could alter the time sequence of the video signal without changing the timing of the audio and would show up as an out of sync presentation. It is going to take some time for procedural details for 5.1 DSS movies to be worked out completely. So, don't worry about it. I think it has nothing to do with your Sony DSS receiver.

Q Many high quality interconnects are directional. It is my understanding that this is because they are only grounded on one end to prevent ground loop hum. I have interconnects running back and forth to my VCR and processor. Should all the arrows be pointed to the processor, or should they still be pointed in the signal direction? Also, I heard people say that speaker cables should be run with the labels going toward the speakers. Is this true?

A Although I can detect differences in the sound between various interconnects and speaker cables, I have never been able to tell a difference between the cable with the arrows pointing in one direction versus the other. However, this is with cables that don't have the ground wire hanging out of one end. Those very well make a difference because you have to connect the wire only at the sending component or receiving component. I know of no evidence to suggest that the labels on speaker cables should be oriented one way or the other. I have seen cables with arrows that are supposed to point towards the amplifier and some where the arrows are supposed to point at the speakers.

Q I have a Harman Kardon FL 8550 CD Player with built in HDCD. The HDCD circuitry has a 20 bit D/A converter instead of the normal 16 bit used for common CDs. The unit comes with a coaxial digital output. I also own a Denon AVR 1700 with dual 24 bit D/A converters. The question is, is the circuitry in the HDCD better than what would be used in the Denon? If I use the analog outs from the CD player, then I will not be using the 24 bit processors in the receiver. If I use the coaxial digital output, will I bypass the HDCD processing altogether? Which method should I use, analog out, or digital?

A HDCD (High Definition Compatible Digital) is a filtering process licensed by Pacific Microsonics in California. There are lots of CDs that are HDCD encoded, but most CDs are not. In order to take full advantage of HDCD discs, you should use the HDCD decoding that is in your player. However, this assumes that the DACs in your player and receiver are the same quality, all other things being equal. Since this is not necessarily so, I would suggest just making a comparison by using the digital output and analog outputs of your CD player to your receiver at the same time, with the digital cable going to one input (e.g., CD player) and the analog cables going to another input (e.g., laserdisc or auxiliary). Then, you can play a non-HDCD disc and an HDCD disc and switch back and forth between the inputs to see which sounds best.

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