Q&A # 54 - March 10, 1998

Staff

Q I own an older Denon DCD 3300 CD player. It has optical and coax outputs and was state of the art in its time. Would teaming this player with a quality DAC make sense, or is it time to get a new CD player?

A The current trend is towards one box players rather than separate transports and DACs. The reason for this is that chips are now available that will do what it took entire circuit boards to do just a couple of years ago. However, the high performance CD players are still noticeably better than the mass market players. So, you would need to spend considerable money to get a player that is better than a nice transport with a good DAC. Therefore, I would suggest getting a DAC for your current Denon, as long as the Denon is in good condition. Spend no more than $1,000, and also consider the possibility of a used DAC. Because of the trend in one box players, you can find good deals on DACs everywhere.

Q I have a Sony A-800K LD player, with a Toslink output but no RF output. In this case, can I connect it by the Toslink to the input jack of AC-3 processor or AC-3 receiver? Will I be able to have AC-3 decoded in this way? I am asking this for the purpose of saving money of buying a new LD player with AC-3 RF out jack, so that I could play LD with Dolby Digital. Of course I understand DVD will be better for DD.

A Unfortunately, the Toslink optical and coax digital outputs from LD players contain the audio information for both the left and right channels. DD is contained only within the right analog audio channel, and DD decoders are not designed to separate the DD info from the rest. So, an RF output on the LD player is necessary, which contains only the DD info from the right analog audio track. If you want to keep your present LD player, MSB Technology (http://www.msbtech.com) can install an RF output for you. For those of you who have Toslink outputs but only coax inputs on your receiver, or vise versa, there are a couple of choices to solve the problem. The Digital Format Translator, available for $95 from Core Sound (http://www.panix.com/~moskowit/DFT.html) converts between the two types of inputs and outputs. MSB Technology makes the Digital Director, which sells for $449. It not only converts between input and output types, but performs jitter reduction. We have not tested either of these devices though.

Q I would like your opinion as to whether a preamp is essential in a system. If we listen mainly to CDs, would it be better to feed the player with the CD volume control directly to the power amp? Wouldn't the signal be more accurate and cleaner? In this aspect , I am comparing the cost of a stand alone player against the same cost with a player and preamp. I am actually using the Golden Tube preamp now. I was thinking of getting either the SONY XA7ES , California Audiolabs CL-15, or the ICONMk2. Which of these would you recommend? In my case, do you think it is better for me to bypass the preamp with any of the CD player mentioned?

A Volume controls on CD players use very inexpensive op amps ($2) to feed the variable level outputs. So, the signal passes through these circuits before getting to the power amplifiers. Using the analog outputs of the CD player through a preamplifier will always give better results. We once used a Sony CD player's variable output jacks to feed subwoofers because the preamp did not have separate output jacks for a subwoofer. But, for high quality sound, don't use the volume controls on CD players for the main signal to the power amplifiers.

Q I'm confused about the potential compatibility of HDTV. Will the new HDTV sets this Fall be compatible with existing DVD players and will the image quality be better than DVD with conventional sets? Will HDTV be compatible with analog delivery such as existing cable, VHS, and laserdiscs, and will the image quality be better than thoses devices with conventional TVs? Finally, will HDTV be compatible with digital satellite and will those images be better than those viewed with conventional TVs?

A All TV images in the United States are NTSC, including DVD, VHS, Cable TV, and DSS, even though some of the formats use digital means of storing or transmitting. They will all be compatible with HDTV (they are supposed to be anyway). The HDTV will sense the type of incoming signal and automatically display it properly. Because the phosphor groups are smaller on HDTVs than on conventional NTSC sets, I would imagine that NTSC images might be a little sharper on the HDTVs, but we will test that when we get one of the HDTVs. There are already a couple of stations broadcasting HDTV in the USA as trials.

Q It's mentioned on your website and elsewhere that DD decoders will decode plain PCM audio, so this means CDs right? I'd like to know how to best take advantage of this function with respect to the CD player that I have with a Toslink output.

First off, my decoder is built into my Yamaha 992 receiver, and my CD player is the 70ES changer from Sony. I also have the Polk 5400 satellite speaker system. With little room for speakers, this seemed a fine selection from the alternatives I auditioned.

I know that it's the audition that really counts. However, tuning the speaker placement in my listening area and my amateur ears at the same
time I find it difficult to decide whether it's better to use the Toslink and decode the PCM in the receiver or use the traditional line
level connection and use Sony's DAC.

I know that Yamaha has some late model DSPs that do the DD decode. I'm guessing it's possible that the following are true:

• the Yamaha chips handle PCM better than Sony's DAC
• if the CD is Pro Logic encoded, the results will be better if the Yamaha is fed a digital signal
• the Yamaha chips reduce/eliminate jitter from the transport/Toslink and not actually make the problem worse

• no RF on the interlink of course

Then again, in Sony's favor is it possible that:

• Sony's DAC is superior
• Sony claims to have some kind of digital filter which is a 'good thing' and helps only with the line level outputs
• The analog interlink losses/interference are not really significant

Q I am considering a Gateway Destination Computer/TV which will hook up through my sound system. The Gateway Destination comes with a 35 inch monitor screen and a DVD drive. I am confused about what I will give up in using this DVD player, as compared to, say, the Sony 7000. I will be using the Yamaha 2092 digital receiver with any system I get. Is the computer DVD the same or very different than DVD players sold for a regular home entertainment center?

A I have not seen the Gateway with a DVD-ROM drive yet. The Sony 7000 is one of the top DVD players out their, but is also the most expensive, excluding the high-performance models. When using the Gateway, you will need to have the DVD run through your PC, so there are more potential problems that might crop up than having a dedicated DVD player. Currently, the DVD technology is maturing at a fast rate much like the computer industry. So both the DVD and DVD-ROMS of today will be better in the coming months.

Q I am trying to find a LCD Projector that supports both widescreen and standard video formats so that I can watch movies in original 16:9
formats. I am having trouble finding such a thing. Is it out, or is it only available in CRT based projectors? Also, what do you recommend as the best LCD solution under $15,000? Primary use is movies in widescreen format. I do not want a CRT because of the sheer size. It is far to
large to look proper in the theatre room in my basement as the ceiling is fairly low.

A Runco makes a series of LCD projectors that all do multiple aspect ratios and they are well under $15,000. You should take a look at the
DWIN HD-500 CRT projector. It is very compact and would probably fit in your room. You can buy it with the DWIN line doubler for under $15,000 and produce a picture that even the best LCD projector could not come close to.

Q I recently bought a Sony S7000 DVD player and am now looking for a widescreen TV to enjoy movies at home. Are there only a few widescreen CRT TVs with component inputs? I have seen the new Sony Wega 29+ACI-, but wasn't impressed with their flat surface screen. The image seemed compressed. I heard that the new 32+ACI- wide screen Wega will not be marketed in Hong Kong. I heard it has only the NTSC system. In that case, I need a PAL to NTSC converter to watch local TV broadcasts. Will this cause degrading of the image? Why are widescreen TVs much more expensive than regular TVs letterboxed ones? The other one on local market is Philips 32+ACI- widescreen TV. Again, it again has no component inputs. Does the 100 Hz scanning rate serve the purpose as a line doubler? Will it improve the image? Any good suggestions on widescreen TVs for use with DVD?

A In the past, there have been no sources outside of the professional industry that had component video. DVD is the first product in the
consumer market to offer it. DSS is capable of component video and is broadcast in this method, but no one is currently using it at the output level. You will see more and more TVs that will offer component video inputs now that we have DVD. Widescreen TVs cost more because they are not being manufactured in the large quantities that standard 4:3 TVs are made. With HDTV, all will be 16x9.

PAL has an additional 100 lines of resolution (625 compared to 525 of NTSC), so yes you will lose some picture quality when converting PAL to NTSC. The 100 Hz figure is the refresh rate, not the scanning rate. This means that the screen is refreshed with a new image 100 times each second. It would improve the flicker effect. The scanning rate is the frequency at which individual horizontal lines are drawn across the screen. For NTSC, it is 60 (the refresh rate) x 525/2 lines, or 15.75 kHz.

I feel that the advantage of a 16x9 display and 16x9 enhanced material on DVD is a far better improvement than component video compared to S-Video, as you gain an additional 33% in resolution.

� Copyright 1998 Secrets of Home Theater & High Fidelity
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