HOME ENTERTAINMENT 2003

 BootLog.co.uk

HomeSoftwareArchiveTop TipsGlossaryOther Stuff

HINTS & TIPS

 

Q

I’ve recently added a Pioneer 50-inch plasma to my AV set-up and now find that the majority of my DVD's have very poor picture quality. I’ve tried high quality leads, I then wondered if it's my DVD player (Pioneer DV-717) but the picture quality of budget Region 2 discs seem really good. I’ve read that studios use edge enhancement to make the picture look sharper and on some discs I’ve noticed a distinct white band around the edges of objects. It’s not too bad when there are only a few objects on the screen, but when there's lots of detail the quality is really poor. THX discs seem to be the worst, am I right in thinking that because this is encoded onto the disc, upgrading my DVD player won't make any difference?
Pete Ratcliffe

A

You are right about the encoding or mastering stage being critical to how a movie looks on DVD. Key in ‘worst DVD transfers’ into the Search box on google.com and you’ll see that you are not alone in your suspicions… However, in your case there may be other contributory factors. Plasma screens, even the best ones, are still not capable of the same kind of performance as CRT-based displays, which are usually better at rendering subtle graduations in brightness and colour and tend to have a wider contrast range and produce a brighter image. Moreover, the larger the screen the more noticeable the imperfections become, so you’ll have no problem spotting them on your 50-incher! Your DV-717 was a good player in its day (late 1998) but there have been numerous advances in picture processing since then, so maybe it is time to upgrade. In theory THX DVDs should deliver superior picture and sound quality, (see Getting Stared), no matter what equipment they are played on but you only get the full benefit on AV equipment that has been THX ‘certified’.

 

 
Q

Can you help me find some reviews for stand-alone TV tuners for a plasma screen? Until now I have made do with using a VCR as the tuner. I'm now looking for something that will give me better sound and perhaps facilities like automatic volume reduction for the noisy bits (like my Sony TV had), teletext, Dolby 5.1 (for the DVD player), etc. Any thoughts?
Martin Winlow

A

Stand-alone TV tuners are a rare commodity these days (see Quick Tip). Most plasma panel owners end up buying the purpose designed tuner box for their display screen, usually because they’re designed to work together and the only one that’s compatible with the panel’s connection and control system. The few external tuners that are available tend to be quite rudimentary, often lacking even quite basic features like NICAM stereo and teletext, let alone fancy stuff like Dolby Digital and automatic volume controls. In any case the best place for a digital surround decoder is in an AV amplifier, or a separate component. Check out the tuner options for your panel, it’s likely to be fairly expensive – typically £300 to £500 -- but it’s probably the closest you are going to get to your wish list, otherwise the only alternative is to get a digital satellite or terrestrial tuner.

  

QUICK TIP

Why are there so few analogue TV tuners on the market? There used to be several high quality models but UK TV broadcasting is in a state of flux, with the growth of digital terrestrial and satellite TV. It would be a tiny market anyway, the UK’s almost unique combination of the PAL I system, NICAM and teletext makes it difficult for manufacturers to recoup costs since there would be no prospect of overseas sales and the demand will disappear in the next few years if the analogue switch-off goes ahead.

 

 

SONY DAV-S550 CONNECTIVITY
I've ordered the Sony DAV-S550 and am a bit confused about how to connect it to my TV. The Sony system has component video out, but no SCART (my TV only has SCART inputs). I've ordered an S-Video to SCART cable, but realise that the quality is not as good as component. I've found various component to SCART cables, so what should I do?

Mark Hyett

A

Because of its size and the fact that it was originally designed for the US the DAVS550 (and its predecessors, the S300 and S500) doesn’t have any SCART connections. Apparently it would have blocked access to the other back panel sockets. The output options therefore are composite video, Y/C or S-Video and NTSC ColourStream component (progressive scan) video; sadly there is no RGB output. Since it is very unlikely that your TV can handle component video or progressive scan (and you would know if it could…) your best bet is S-Video and the lead you’ve ordered should do the trick, assuming your TV has an S-Video input on the SCART (you should double check!). There’s no such thing as a component/ColourStream video to SCART lead, though you can get RGB (which is technically a component video type signal) to SCART, which is probably what you’ve seen.

 

QUICK TIP

RGB video connections can get quite confusing. There are actually four ‘components’ in an RGB signal, the separate red, green and blue colour information plus a synchronisation signal, which is the video equivalent of the sprocket holes in movie film and ensures a steady picture. However, there are various ways of handling the sync signal, it can be superimposed on one of the colour signals (normally green) or it’s carried separately, (usually a composite video signal) and the sync information is ‘stripped’ out by the display device.

 

 

CONNECTIONS AND DECODING
I recently bought a Toshiba DVD audio player to go with my Denon AVR1800 amp, cable decoder VCR and Philips widescreen TV. I have two queries: will Toshiba's 24 bit/192 KHz decoder override the Denon's own decoder and I want to get the best connections possible. The decoder and DVD have RGB SCART sockets, the VCR a standard SCART and the TV has an RGB and an S-Video SCART socket as well as front S-Video socket for camcorders. I wondered whether I could use a two way automatically switched adaptor to connect decoder and DVD and use the other SCART for the VCR?
Michael Dennis

A

There’s no question of the Toshiba player overriding the AV amplifier since the two 5.1decoders (one in the DVD player the other in the amplifier) operate independently. If you want to use the one in the DVD player you must connect the 6 analogue channel outputs to the corresponding channel inputs on the amplifier. To use the decoder in the amp simply connect the player’s optical or coaxial bitstream output to the amplifier. Bitstream audio is basically raw unprocessed data, as it comes off the disc, so all of the decoding is carried out by the external decoder in the amplifier. In theory the decoder in the player should deliver the best sound but make a point of listening to them both. Ideally the DVD player should connect straight to the TV’s RGB-configured SCART socket, using a  ‘fully wired’ cable; the VCR and cable decoder can be daisy-chained and connected to the TV’s second AV input using SCART cables.

 



Q
On the back of your recent excellent review I have bought a JVC AV28R25EKS television. I have also ordered the optional JVC SPR100 rear speakers. I understand this will give me DPL surround sound. But isn't the TV's speaker set-up (sub, L+R, centre and rears) effectively a 5.1 set up? What sound option should I select on my Pioneer DV444 to output?  I’m confused.
Andy Balfour


A

A ‘5.1’ surround sound system like Dolby Digital or dts comprises six entirely separate or ‘discrete’ digitally encoded audio channels. The ‘5’ represents the four front and rear stereo and the single centre-front channels, which all have a wide frequency response – comparable with CD. The sixth channel (the ‘.1’ in 5.1) carries only low frequency effects (LFE) and is normally used to drive a sub woofer. Dolby Pro Logic on the other hand is a much simpler four-channel analogue surround system driving front stereo, centre front and a pair of rear effects speakers (with a mono signal). The centre and rear channels are not separate entities as such but encoded within a normal two-channel stereo signal therefore have a comparatively narrow bandwidth. The extra sub woofer output you sometimes see on DPL equipment is derived by extracting bass frequencies from the front stereo and effects channels. All DVD players have an analogue ‘mixed stereo’ output as standard (see Quick Tip), which carries the Dolby Pro Logic information that’s fed to the decoder in the TV, so you shouldn’t need to make any adjustments to the player.

 

 

QUICK TIP

The analogue stereo output, fitted as standard to all DVD players, carries 4-channel Dolby Surround information that has been ‘downmixed’ from the movie’s digital 5.1 surround sound channels. The four channels are ‘phase matrixed’ into the two stereo channels and can be extracted by a TV or amplifier with a Dolby Pro Logic decoder. Stereo and mono soundtracks on old movies made before surround sound are processed in the same way but only use one or two of the six or more available digital channels. 

 

 

Q
I think I've heard that it's harmful to your PC monitor if you have the speakers right next to it. Is this true and is it the same for hi-fi speakers next to a TV? Is it OK as long as you don't have the TV and speakers/hi-fi playing at the same time? Why shouldn't it be safe since the Aiwa VXD2150K I am looking to buy has its own speakers attached at the sides?
Phillip Kingston

A

You are referring to magnetic ‘staining’ or colour impurity, which occurs when a strong permanent magnet, like those in loudspeakers, is placed close to a TV screen or PC monitor with a cathode ray tube (CRT) display. Inside the picture tube there’s a thin, perforated metal plate called a shadowmask or aperture grille. This is used to guide the beam of electrons from the electron gun in the neck of the tube onto the coating of phosphor dots or stripes on the screen. If the metal plate becomes magnetised, even very slightly, the electron beam is deflected off course resulting in patches of incorrect colours on the screen. 

 

The speakers built into TVs and monitors and those sold for home cinema use are normally magnetically shielded so they can be placed close to the screen without affecting it. Nevertheless, TV screens can still become magnetised by fields generated by electrical appliances or nearby metal objects (radiators etc.) and even the earth’s own magnetic field. To counteract that most TVs and monitors have what’s known as a ‘degauss’ coil attached to the outside of the tube. When the TV or monitor is switch on, and before the picture appears, a voltage is applied to the coil and steadily reduced over a period of a couple of seconds. This generates a ‘collapsing’ magnetic field that has the effect of neutralising any magnetism in the tube (see also Quick Tip).

 

QUICK TIP

Occasionally the magnetic staining on a TV or monitor screen can become so severe that the automatic degauss circuit cannot cope. Some PC monitors have a manual degauss button but in some cases it may be necessary to manually degauss the screen. TV and video engineers use an extra powerful electromagnetic coil, shaped like a large hoop or a thick wand, which they wave around in front of the screen in a mysterious way, gradually moving it further from the screen to ‘erase’ the magnetic fields that have built up on the shadowmask or aperture grille.

 

 

 

Q
I was looking at your website and read the review on the Goodmans GDVD 125 DVD player. My player can also play MP3s but when I saved a lot of MP3s to a CD-R the DVD player won't play them. It says no disc. I use Nero Burning to copy the MP3s to CD-R; I copied them without using folders.
David Johnson

A

There’s very little to go wrong and it normally doesn’t matter whether music files are stored on the disc in the root directory or in folders, though you should try the latter method, just in case... Nero Burning is a perfectly good burner program, but you should experiment with the various options. In later versions (V5.5 onwards) this includes an MP3 recording mode, which checks the validity of the files. However, if the problem persists the most likely cause is the discs themselves and there is a big variation in the quality of blank CD-Rs. There’s quite a lot of rubbish on the market and cheap discs, sold on bulk ‘spindles’ of 50 or 100 – especially those that turn up in computer fairs and market stalls – may be second or third grade, or even reject stock. Unfortunately there’s no easy way to tell from the outside, except for the price… Try again but this time use top grade discs from a well-known manufacturer, bought from a reputable stockist. 

 

 

QUICK TIP

Many new DVD players can play MP3 music files recorded on CD-R discs but only a small handful can play and display JPEG picture files. However, you can create still picture slideshows, that will play on most DVD players, if they’re recorded as Video CDs. Various software applications will do this for you, including later versions of Nero Burning and try-before-you-buy shareware titles such as Photo2VCD (http://www.photo2vcd.com/) and Xat Show (http://www.xat.com/). Some of the more sophisticated programs also let you add transitions between pictures (wipes fades etc.) and background music.

 

 

CONNECTIVITY
I currently have a Toshiba 32-inch TV which comes with surround sound from the supplied two front and two rear external speakers and built in (to the TV) sub-woofer. I'm thinking of acquiring a recordable DVD player and a dedicated surround package with sub-woofer. How does one connect these to a TV, which already has speaker outputs and built in sub-woofer or is this more straightforward than I imagine?
Catherine Kindreich

 

A

Since you are buying a surround sound system you won’t need to use the one in the TV for DVD moreover your new package should include a more effective decoder and better speakers, especially in the sub woofer department. The amplifier will probably be more powerful than the one in the TV, and sound quality benefits from the fact that it is in a separate box, well away from all of the other signals flying around inside a TV. The simplest connection method – assuming that your TV has an RGB input (most Tosh models do) and the DVD recorder is also equipped with an RGB output -- it’s a common feature -- would be to use a fully-wired SCART cable between the two; just make sure that both items are configured for RGB by visiting their respective setup menus. You should also connect the DVD recorder’s bitstream audio output to the appropriate input socket on your surround sound system. This arrangement will give you the best of both worlds. When watching a movie on DVD mute the TV sound and switch on the surround sound system but if you just want to watch a TV program or a recording you’ve made then listen to it through the TV’s sound system.

 

 

GETTING STARTED 1 – THX MASTERING

THX is not a technology as such but a raft of rigid quality control measures that ensure all of the elements in a movie going from film to DVD, from the mastering process through to the display screen in your home, delivers the best possible picture and sound.

 

Engineers from THX are closely involved with the transfer process from the very beginning, and all of the equipment used in the transfer first has to be calibrated to ensure correct and consistent colour balance, greyscale, contrast, white and black levels, frequency response and audio recording levels. THX engineers work with the company to advise on technical matters but artistic decisions, such as content and how a movie looks (colorimetry, texture and so on) is the responsibility of the filmmaker.

 

When the film to video transfer has been completed THX engineers are called in again to oversee the production of a digital copy or ‘clone’ of the creative master recording, which also involves the insertion of THX test signals. Meanwhile the movie’s audio content goes through a similar process with THX engineers providing technical backup before and during the mixing and mastering stages and helping with the encoding of the various soundtracks.

 

The digital video and audio masters come together at the DVD authoring stage and once again THX is there to provide technical support, particularly with regard to the compression systems used. The type and level of compression defines the look of the movie and its freedom from artefacts (jerky movement, blurred movement, block noise, pixellation etc.). Finally test DVDs from the finished master are reviewed by THX engineers, who have the final say over quality control and whether the disc can go into production.

 

Officially the name THX comes from one of George Lucas’s first movies ‘THX 1138’, though others say it is short for the Tomlinson Holman eXperiment, Holman being a pioneering engineer working for Lucasfilm. 

 

 

GETTING STARTED 2 – MP3 on DVD

 

The MP3 replay feature on most recent DVD players seems to have caught a lot of people on the hop so let’s try and make some sense of it. MP3 is short for MPEG1 layer 3, which is the audio system used on the now largely defunct Video CD (VCD) format. Sound is recorded as highly compressed digital data, which means a lot of music can be packed into a relatively small space. MP3 would have sunk with Video CD but it got a new lease of life as an efficient way of sending music over the Internet. This spawned a huge and largely illicit trade in music ‘ripped’ from albums via so-called ‘file-sharing’ sites like Napster. File sharing is still rife though nowadays even the major music companies are getting in on the act and attempting to sell music on-line. 

 

Initially most MP3 music, downloaded from the Internet, stayed on the PC or was transferred to ‘personal’ MP3 players on memory cards. It’s always been possible to store MP3 files on recordable CDs – between 10 and 20 hours worth per disc -- but until fairly recently they could only be played on other PCs. Then, about three years ago the first CD players with MP3 playback began to appear followed soon afterwards by DVD players with MP3 capability. Ironically it’s been a built-in feature almost from day one since most DVD players can also play VCDs and consequentially had the capability to decode MPEG1 data but until recently lacked the necessary ‘firmware’ that would allow players to directly read and decode the data files.

 

---end---

 

Ó R. Maybury 2002, 0312

 

 

 

 

 

 

[Home][Software][Archive][Top Tips][Glossary][Other Stuff]


Copyright (c) 2005 Rick Maybury Ltd.

admin@rickmaybury.com