Q&A # 275 - February 15, 2002

Staff

Q I want to buy the best S-Video cable, but I'm confused. Is Nordost Optix or Wireworld Starlight or another you might know of the best? What cable should I buy?

A I tested a few S-Video cables some time ago, and could not see any difference in the video quality. However, the build quality does vary. Either one of the products you mentioned should be fine, assuming they are 75 Ohm impedance. I am not sure on these particular models since I don't have them here. Ask before you buy. Don't purchase low priced bargain cables, because they are likely to break down over time if you plug and unplug them over and over. For example, the S-Video cable that ships with the iScan Pro is bad. There is some type of cross-talk between chroma and luma. This shows up as a waffle appearance on chroma.

Q Currently I own a Toshiba 36AF41 television coupled with an older model Sharp VC-H810U hi-fi VCR and Kenwood DVT-505 home theater in a box. Added is a Toshiba SD 2300 DVD player.

I am thinking about getting Direct TV instead of cable, and I need to know if I need a special satellite receiver box such as the RCA DS4285RG to receive and process Dolby signals and get the best audio/video for my system. Also would I have to upgrade my VCR to fit this system?

I know the Kenwood DVT-505 is not high end but it does have an optical input to lead in from the Direct TV receiver. However theVCR needs to be hooked up as well. The Sharp VCR has channel coverage to 1-125, and this I think might be a problem.

A First, make sure the satellite box, sometimes called an STB or set top box in the case of High Definition, has to be a DirecTV box (the packing box will have a label stating that it is for DirecTV). Secondly, the satellite box has to have a Dolby Digital output jack, and this also will be stated on the packing box, or in the instruction manual. If it is not clear, ask the salesman for confirmation that the box you are considering has this feature. If the audio output for the DD is Toslink optical, your receiver must have a Toslink optical digital input. Otherwise, you would need to buy one of the Toslink/Coax converters we have discussed from time to time. Third, your current VCR will work fine because the channel decoding is done by the satellite box. Connect the S-Video output from the satellite box to your TV, the Toslink DD output to your receiver, the composite video output from the satellite box and stereo coaxial analog audio output from the satellite box to your VCR. 

Q I have recently acquired a Panasonic 16:9 direct view HDTV. I also have the Proceed DVD transport (PMDT) with the progressive scan processor (PVP). The PVP accepts video inputs from other sources and outputs a 480p component signal. Consequently, the only video input to the HDTV is a 480p component signal. The question is: What calibration needs to be done to the HDTV considering that I am bypassing much of the internal circuitry?

A You would make your adjustments starting with the PVP processor, and finally, the TV itself. Otherwise, you might have an odd setting at the player that you have to compensate for downstream. Use the Avia disc and calibrate the system.  You do not want to touch the controls in your DVD player (turn edge enhancement in the player off). These controls are usually done in the digital domain. You may end up compressing the dynamic range of the signal or clipping the video signal.

Q I am currently using two Parasound HCA-1000As bridged for my front R/L speakers (approximately 400 watts into 8 Ohms). The center channel and surrounds are driven by a B&K Components ST-1430, which is approximately 125 watts/channel into 8 Ohms). The fronts and center are Paradigm Reference Studio 40s v.2 and Studio CC, respectively. All of this is controlled by the Parasound AVC-2500u. My question is this. With ~400 watts into the Left and Right channel, it is hard to balance them in Dolby Digital with the center channel that has 125 watts. I could use the gain controls in the back of the Parasounds to lower the output, but would I not be defeating the purpose of bridging the two HCA-1000As? Would I be better served by using just one of the HCA-1000As to drive the two front speakers so they match the wattage of the center speaker?

A The center channel gets most of the sound, with surround sound audio, so it should have at least equal power with the front left and right channels. What I would do is use one HCA-1000A to drive the front left and right speakers, and the other HCA-1000A to drive the center. Use the B&K to drive the rear surround, and perhaps a rear center for EX at some point.

Q I'm using M&K s125 speakers with aragon 8008st and the 8008x3 amplifiers. I want to upgrade to 7.1 but I'm not sure what I want to do with my amps. Should I get the 8008bb or mkll? Or should I replace the Aragons and get a Cinepro 3k6SE and the 1k2SE/XC? Or maybe Bruston 9BT?

A You have a great deal of money invested in Aragon, and they are very fine amplifiers, so I would suggest getting another Aragon. Bryston has a similar sound to Aragon, so you could go Bryston as well. However, the Cinepro sounds quite different than Aragon and Bryston, so Cinepro would not be the best choice to pair with your existing Aragons. If you were starting out though, not already having some other amplifier, the Cinepro 3k6SE is superb. We use one here as a reference home theater power amplifier.

Q I am currently in the market for a rear projection HDTV. I have read many reviews about the various models that are currently available out there. I've also read about the different formats: 480p, 720p, 1080i. Toshiba even has 540p although I have no idea what that's all about. My question pertains to the HD formats. How important is 720p? I've read that 720p is soon to be the new standard. I've also seen that most of the TV networks are broadcasting 720p. What format will HD-DVD or other HD software likely to be when they become available? Should I hold out for a RPTV that supports 720p? Should I settle with 480p and 1080i? I don't plan on buying another TV after this next purchase anytime soon. So I'd like to make the right choice for future compatibility and the best picture for my dollars. What do I need to pay attention to while I'm shopping?

A 720p requires a higher scan rate, but 1080i has more resolution. So, if you want 720p, you need to make sure the TV will scan that high. With CRT RPTVs, 9" CRTs will resolve most of the detail of 1080i. However, they cannot resolve all the detail. TI demonstrated a 1920 x 1080 chip a couple of years ago. They don't plan to introduce them in the consumer market. They want to keep them for D-Cinema. This will ensure that the movie theater delivers a better picture than home. However, if pressure comes from competing technology, like D-ILA, then TI might move sooner. DLPs and LCDs do handle 1080i. They simply scale them down to the native rate. In fact, the Sony 10HT can resolve 1080i HD better than most CRTs.

Most consumer RPTVs do not support 720p and may never do so because of the higher cost. DLPs will handle 720p, but all the TV program content is 1080i. The perceived vertical resolution drops in half during motion (540p) while 720p retains full vertical resolution all the time. I doubt we will ever get true 720p content from the broadcasters, so we are stuck with 1080i. Displays can't handle 1080p, so 1080p will not happen for a very long time. I do believe 1080i should be deinterlaced to 1080p and then scaled down to 720p for DLPs. This will offer an improvement over what we get right now. It is just a matter of cost. DVD is mostly for movies, which means film, and so, I would hope HD-DVD would be 1080i, with up-conversion to 1080p. The next TV I buy will be HDTV, and it will be 720p-capable, along with 1080i full resolution capable. It will have DVI and Firewire inputs. It will have a 16:9 screen, at least 72" diagonal in size. I will probably have to do a lot of looking to find one like this.

Q When watching TV or DVDs (more on DVDs) on my RPTV, if I look closely I can see a double of the image almost. Mostly around peoples faces. It's like when you stare at an object and you see the end extending more because of the difference in each eye. Is this normal? Is it because I'm sitting too close to the TV? About 8 Feet.

A Without being able to actually see what you are talking about, I suspect this is due to the projection lenses. Good lenses are extremely expensive, and the lenses in RPTVs don't have enough attention paid to them, perhaps because consumers don't think about them as integral to a good image. The lens element surfaces reflect back onto lens elements behind them, so lens coating is very, very important. I think this is where your ghost double image is coming from. Often, the lens elements are all plastic. Glass lenses are much more expensive. They have to be ground and polished, while plastic lens elements can be pressure injection molded and then polished. If we ask those sorts of questions when shopping at this point, expect the salesman to say he does not have any idea whether the lenses are plastic or glass. But, if we keep asking, sooner or later, the manufacturers will build them better because we know enough to ask about them.

Q I have looked at several "HDTV's" and found that they didn't actually have a high enough pixel density on the screen to actually do 1080x1920. I am now looking at the Sony KD-34XBR2. I cannot find any information on how many stripes it actually has on the tube. Am I totally out to lunch thinking that they would need at least 1920 to do the HDTV job?

A For a direct view TV, there would indeed have to be at least 1920 stripes (a stripe contains an RGB phosphor set) to do 1920 across the screen. However, direct view TVs will not resolve 1080i. They have a shadow mask that limits the final resolution.

� Copyright 2002 Secrets of Home Theater & High Fidelity
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