Q&A # 116 - May 18, 1999

Staff

Q In reference to Question No. 3 in Q&A #115 (May 11, 1999), with regard to DVD players from overseas being brought to the USA, I assume the person asking this question is stationed with the U.S. Govt in Europe. If so, Region I players and DVDs are available through his/her local military exchange. Also, the Army and Air Force Exchange System (AAFES) has a website that offers excellent mail order prices on DVD players (no tax or shipping charge) to authorized customers. The website is http://www.aafes.com. This is not an advertisement for AFFES (I don’t work for them), just information. I don’t know about the cycles part of the question, because unlike Europe, Asia uses 60 cycles. I do know there are transformers available in Europe to alleviate this if it is a problem.

A Thanks for the info.

Q I am interested in purchasing a Kenwood Dolby Digital receiver and have a question about inputs/outputs. Is it necessary to have S-Video Ins/Outs to connect a DVD player to the receiver? I am somewhat confused about what I need. I have a stereo TV, and I will be purchasing a DVD player to go with my current hi-fi VCR.

A With DVD, you will get a much better picture if you use the S-Video ouput from your DVD player rather than the composite video output. However, you don't have to use the video connections on the receiver, regardless of whether it is S-Video or composite. Instead, you can simply run the video output from the DVD player directly to the TV, and in fact, you may get better video this way if the circuits in the receiver video switcher are not high bandwidth. Since you cannot copy DVDs, it is not necessary to run any outputs from the DVD player to your VCR. VHS video is low bandwidth, so it would be perfectly alright to run the VCR video output to the receiver, and from there, to the TV.

Q After reading several reports on how good component video looks, I went out and purchased a Sony rear projection TV (53" V series) and the highly rated Toshiba 2108 DVD player, both of which have component video connections. I hooked them up with $70 AR-thick component cables and switched back and forth with the S-Video cable that came with the Toshiba. To my astonishment I could not see any difference in color or clarity between the two. So did I just spend a lot of money getting these two units for nothing? In the future I think I'll view and listen to anything else I buy instead of buying based on some hi-fi TV quote (experts).

A No, I don't think you wasted your money. However, most of the improvement in color and clarity is when you move from composite video to S-Video. Improvements between S-Video and component video are very subtle. It is like audio cables. Some people can hear differences while others can't. Once you lock on to what the differences are though, they will be more easily apparent to you.

Q I've read about how D'Appolito array center channel speakers suffer from poor off-axis response, so I'm wondering why do so many companies (even "high-end" ones) build center speakers this way?

A If the speakers are arranged so that the two mid/bass drivers are on the ends with the tweeter exactly in the middle and in line with the centers of the mid/bass drivers, then it is D'Appolito. Some speaker companies use this configuration, matching the other speakers, because it keeps the price down. All the speakers are the same, with the center one just turned on its side. However, many of the speakers just give the appearance of being D'Appolito. If there is a fourth speaker, such as would be the case if there were two mid/bass, an upper mid, and a tweeter, where the tweeter is not directly in line with the mid/bass drivers, then this is not D'Appolito, and it would not have the poor off axis response of a true D'Appolito laying on its side. But, you are right in that some manufacturers use the D'Appolito configuration for all the speakers including the center channel, and in this case, the center is not going to perform very well.

Q I have a large center channel speaker (Ariel). Is there any advantage to using one speaker setting over the other on my receiver insofar as directing low frequencies from the center channel to the subwoofer is concerned?

A Unless you had very small speakers, I would suggest using the large speaker setting on the receiver, because the high pass is around 80 Hz - 90 Hz for most receivers. In my opinion, this is too high because you can perceive directional cues for frequencies above 50 Hz, and this would throw some of your center channel sound to the subwoofer that you could perceive direction for. In your case, because of the size of your center channel speaker, I would say that, definitely, you should use the large setting.

Q I am currently shopping for a system that could include entry level separates. I have seen advertisements for "closeout" products such as B & K AV2500 series one for $300, Harman Kardon PA5800 for $400, and the Carver AV-705x for $800. I read your review of the Carver. Do you still use that amp and could you update your opinion of it for me? Are they going out of business? Any opinion on the other two? Do you see much difference in comparing this level of separates to what is found in the Yamaha 795 or 995 for example?

A Closeout specials can be tremendous bargains, and I consider the Carver AV-705x to be one of them. Yes, I still use the one we have here. I have no reservations about recommending it, even if it were not on a special sale. However, receivers are another situation entirely. While power amplifiers don't need upgrading, older model receivers can be a problem if you get something that is not compatible with the all the new technology that has arisen in the last few years. Because outboard DD/DTS decoders are getting rare, I would have a hard time recommending an older model receiver that does not have DD/DTS, even if it has a set of 5.1 input jacks. If you said you were not interested in DD or DTS, I think you would change your mind within a year or so. However, if you can find an outboard DD or DD/DTS decoder at the same time you are getting an older model receiver with the 5.1 input jacks, then that would work fine. You just don't want to be left with a receiver that has the 5.1 input jacks, and not be able to locate an outboard DD/DTS decoder. Lastly, regardless of the high quality of these products, make sure you have some sort of warranty (in writing) for repair when you buy them, since Carver Corporation, for example, is currently not in business. A third party warranty might be considered. That is where you send the product to a company that specializes in repairs, but it is not necessarily the manufacturer. The store where you buy the product should be able to offer the third party warranty.

Q I recently bought a HD (High Definition) compatible display (Toshiba TW65H80) that I want to mate with an HD decoder/ tuner. I tried a Sharp TU-DTV1000 decoder that I am feeding the RP (Rear Projector) a 1080i signal via its RGB outputs. NBC's The Tonight Show looks wonderful, but there is a serious audio distortion problem with the DD signal from both digital outputs as well as the analog outs. Sharp confirmed that I got a defective decoder so I returned it. What other HD decoders are currently available that will send 1080i and what new products are coming? My dealer has offered to let me have a demo Unity Motion decoder at the same price as the Sharp. I'm concerned about UM's financial status and don't want to buy a product without future support.

A Early adopters, like yourself, myself, all of our writers, and most of our readers, pay a price for wanting all that new stuff before the paint is dry. Bug, bugs, and more bugs. But, it's still lots of fun, isn't it? Thomson DTV decoders, marketed under ProScan and RCA, will start below $700. For the expensive DTV decoders, I would suggest looking for one that has upgrade possibilities. This could be a matter of adding internal cards, or perhaps a written guarantee that you can turn in the old decoder towards the purchase of a new one. Other than that, many companies have DTS decoders coming out relatively soon. There will be some package deals that give you a price break if you get an HDTV satellite dish along with the HDTV.

Q I am using a Carver CT-24v preamp connected to a Carver A-500x power amp and an AR S12HO subwoofer (via splitting the preamp outs). The interconnects are Monster Cable I400 MkII, and my main speakers are Magnepan MG 1.5s. When I switch different inputs on the preamp, the speakers make a two stage popping sound, first high frequency then low frequency. This popping sound is always at the same level regardless of the volume setting. I was wondering what causes this and if I could fix it. My AR sub will sometimes make a very loud popping sound when I switch it off, but sometimes it is fine. Do you know what might cause this?

A This is caused by transient DC voltages that occur for a short time across output/input connections. The initial popping is when the DC first occurs at the time you make the input change. The subsequent noises are probably the input or output capacitors discharging the voltage they stored from that DC surge. This sort of thing drives most of us crazy, but since they are usually not very loud, they won't hurt your equipment. They are just annoying. You find them most often with separates, which use the input capacitors in case of DC that is output from the component feeding it. Any residual DC voltage that stays after the equipment has fully warmed up and settled down, is called DC offset. It can cause speakers to be slightly away from the true resting position when there is no music playing, and this can result in distortion. DC offset of more than about 30 millivolts is considered unacceptable. I have not tested any preamplifier or power amplifier with anything approaching that level however. Usually it is in the microvolt range or just a few millivolts.

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