HomeSoftwareArchiveTop TipsGlossaryOther Stuff






Name              Nigel Hollier, via email

Kit                   Hitachi C2886TN 28-inch TV

Problem            Nigel says is quite new to this home cinema lark and is a bit confused about how to proceed with an upgrade. It seems he has tired of his Hitachi TVs 3D sound feature and now wants to experience the delights of Dolby Pro Logic, which prompts a couple of questions…


He knows that Hitachi market a set of infra red speakers for the C2886TN and that the transmitter is powered by an 18-volt feed from the TV, so far so good. However, he goes on, he has heard mixed opinions on these speakers, what do we think of them, he asks? Also, what sort of range can he expect from the infrared signal, do they have to be a certain distance from the TV he wonders? If he were to install these speakers where would the centre channel come from, is there a speaker in the TV or do the right and left speakers produce a 'virtual' centre channel? 


His last question concerns using the rear panel connections on this TV, which he says is another option he's considering. The manual says there are four audio output labelled S (rear surround amp and speaker) C (centre amp and speaker), R (front right amp and speaker) and L (front left amp and speaker). Nigel wants to know does this mean he needs four separate amplifiers, or is there one that will do the job? Secondly, why is there only one output for the rear surround speakers, and last but not least, does the amplifier need to be a Pro-Logic receiver, or is this work already being done by the TV?


Expert Reply             We'd better start with those infra red speakers. As far as quality is concerned the Hitachi units are not too bad they're certainly adequate for a typical living room. The point about the Dolby Stereo in general and the rear surround channel in particular -- and this will answer one of Nigel's other questions – is that it's a matrixed analogue system and the quality is not that wonderful, compared with more recent 5.1 digital surround systems. Moreover, unlike Dolby Digital, the rear channel is mono (but fed to two speakers), which is why there's only one output on the back of his TV. The bandwidth of the rear channel is quite narrow with an upper frequency cut-off at around 7kHz. In other words it is not very demanding of an amplifier or speakers. The maximum range of the Hitachi infra red speakers is around 5 metres, beyond that noise levels increase to intrusive levels, however, that's unlikely to be a problem, unless Nigel lives in a baronial mansion, in which case he needs a much bigger TV. The real problem with IR speakers is that the receiver must be in clear line of sight of the transmitter module, so he can't go hiding them behind the sofa.


The C2886TV doesn't have a built-in centre channel speaker (there's one in the optional console stand) and has Nigel suggests the set generates a phantom dialogue channel from the front stereo speakers. The audio sockets on the TVs rear panel is the four line-level channel outputs from the set's on-board Dolby Pro Logic decoder, so no, Nigel will not need to purchase a Pro Logic receiver-amplifier. He could use a stereo amp to drive the surround and centre channel speakers or got for the full Monty and plumb in a four-channel AV amplifier-processor. However, he might want to think about a spot of future proofing and go for a 5.1 channel AV amp or AV receiver, possibly with built-in Dolby Digital and DTS decoders. These days they only cost slightly more than regular 4-channel AV amps but it could make his life easier if and when he buys a DVD player.





Name              Nicholas Gibbons, via email

Kit                   Sony 28-inch TV, Sony TA-AV790 AV amp, Pace satellite receiver

Problem            The digital future beckons Nicholas and he wants to be ready for it. He says that when, eventually, broadcasters transmit programs in Dolby Digital he would like to be in a position to take advantage of it. He's planning to purchase a DVD player and a digital satellite receiver. He wants Dolby Digital and assumes that he will need to buy a new amplifier, but will he need to upgrade his speakers to get the best effect? He goes on to say that he would like to receive free-to-air terrestrial digital services. Would it be better to wait until widescreen TVs with built-in digital decoders are available as the best way of achieving this?   


Expert Reply             Although in theory the UK's digital satellite and terrestrial broadcasting systems have the capacity to carry Dolby Digital soundtracks the chances of it ever happening are extremely remote, in short Nicholas shouldn't hold his breath. For the foreseeable future Dolby Digital will be confined to DVD and currently the choice is between players with a datastream output, where the raw Dolby Digital, MPEG and DTS 5.1 digital signal has to be fed to an external decoder-amplifier. The alternative is players with built-in decoders. The latter have a set of analogue, line-level outputs, one for each channel. In both cases he will need a multi channel AV amplifier – with or without a decoder -- depending on the type of DVD player he buys. The cost of the decoder chips has fallen dramatically so there's not a lot in it nowadays, so it's up to him whether they're in the DVD player or the amplifier. It's usually a good idea to start with the player and get one with the facilities and price that suits him, then decide on the amplifier. In general it is better to go for a set of AV speakers, the better ones are optimised for the dynamics of movie soundtracks and the front stereo and centre channel speakers will be magnetically shielded, to prevent colour staining on TV screen.


Widescreen TVs with built-in digital terrestrial and satellite decoders have been available for some time. The problem is that at the moment they look like a fairly poor deal, when compared with the alternative of a widescreen TV and a free set-top box. Because digital TVs are not subsidised the cost of the decoder is added to the cost, which basically means you'll be paying an extra £200 to £400 for the privilege of a TV with a built-in decoder. Manufacturers are pressing for a change and the cost of decoder chips is falling, so hopefully the situation will improve quite quickly. There's also the added difficulty of dual-standard (i.e. satellite and terrestrial) operation. Most digital TVs should be able receive both services, but this depends on the development of the so-called 'sidecar' modules, which has been repeatedly delayed and are not now due until the Summer. There's also a question mark as to whether upgraded sets will be able to receive all of the proposed interactive services. Our advice is wait and see, the picture should become clearer over the next few months. 



Name              Bill Perry, via email                          

Kit                   problems with video projectors      

Problem            Vertical lines and a picture that looks as though it is passing through a fine wire mesh is troubling Bill. To date he has sampled four video projectors; all of which he says have a number of annoying faults. He says the picture on a demo Philips SV10 Hopper looked okay but the one he was going to buy produced bright vertical lines. The picture on a Philips XG10 showed black vertical lines in both video and data modes. The same problems afflicted a Mitsubishi XGA projector, he says he was impressed with the picture from a Sony XGA projector but could not live with the noisy fan. The sales engineer at his local dealer admitted he had not noticed the effects but agreed with Bill that once the defects were pointed out they became intrusive and unsuitable for video. He wonders if that since these projectors are sold for data display the corporate market isn't so choosy about video performance?  Bill finishes off by saying that on a recent visit to a well-known high-street purveyor of AV equipment only one of the ten digital televisions on display was showing a correctly focused picture.    


Expert Reply  we couldn't agree more with Bill about the way digital and widescreen TVs are presented in showrooms. All too often 16:9 TVs are left showing incorrectly formatted pictures. The trade really needs to get its act together on this one. Stand by a display and you will overhear customers commenting that the picture looks 'all wrong' or distorted. This kind of carelessness is actually putting people off buying widescreen TVs!   


As far as video projectors are concerned, the fact that Bill has seen models that produce a satisfactory picture, without vertical lines, suggests that there were problems with the projectors concerned, the video source  or the connections being used. The lines sound a lot like 'spooks', which can be caused by cabling or interference from other nearby equipment. We have extensively tested both video only and data-video projectors and have not noticed any difference between the two types. The 'wire mesh' patterning is characteristic of simpler (i.e. single element LCD) models, and it depends how close you are to the screen. It's much less of a problem on triple element models and at normal viewing distances the granularity should be all but invisible.



Name              Jack Hodgkiss, via email                                                  

Kit                   JVC AV-32WP2EK TV           

Problem            Jack is mostly satisfied with his JVC TV however, when the picture displays a large bright expanse of colour or white he hears a loud spitting, buzzing and cracking sounds. When darker colours are shown – even if the background is bright – the noise stops abruptly. He has tried adjusting the colour settings but all to no avail.            


Expert Reply             Rapid changes in brightness do generate some fearsome static charges on and around the picture tube and these can be heard as crackles and clicks if you listen closely to the TV, it's usually a lot worse when the atmosphere is dry or in well-insulated centrally heated rooms. The crackles can be picked up by the audio system, so if Jack is using a external amplifier he should make sure he's using good quality cables throughout, and try re-positioning the amplifier. He could try a room humidifier and see if that makes a difference, otherwise there may be a fault on the TV and he should have it looked at.       




A couple of this month's letters has highlighted the fact that a lot of newcomers to home cinema are confused by the various surround sound technologies on offer so here's a quick one-minute primer. The most basic system is 3D or pseudo surround. This is where the TV (or AV amplifier) generates an artificial spatial effect from a mono or stereo soundtrack, making sounds appear as though they are coming from some distance away from the speakers. It's not genuine surround sound but it can make old movies and TV programmes sound a bit more interesting.


The next step up the ladder is Dolby Surround. Four channels of information (right and left stereo, centre dialogue and rear surround) are encoded into a normal 2-channel stereo soundtrack. The channels are extracted by a Dolby Pro-Logic or 'active matrix' decoder (older passive matrix decoders are no longer used) and fed to speakers surrounding the viewer. Dolby surround is an analogue system and designed to be compatible with regular stereo sound systems (NICAM stereo, VHS hi-fi etc.). The dialogue and rear surround channels have a fairly narrow bandwidth and they can be a bit hissy but this isn't a problem since they're only carrying speech and sound effects. Some TVs, notably JVC's 3D Phonic models have a DPL decoder that extracts the rear and dialogue channel and feed them through the stereo speakers, creating a more dynamic spatial soundfield.


DVDs also carry Dolby Surround soundtracks on the format standard mixed stereo audio channels but they also have separate or 'discrete' digital CD quality audio channels, used for Dolby Digital, MPEG audio or DTS cinema soundtracks. These are the basis of the so-called 5.1 surround sound systems with high quality front stereo, centre dialogue and stereo rear effects channels, a sixth narrow band channel carries bass information used to drive a sub-woofer.  







Name                          Pavlos Symeonidis (** address below)            

Kit                               problems with DVD and a video projector

Problem                      Pavlos is not happy, he says HE convinced him to buy a DVD player, surround sound player and video projector (he doesn't say which models) but thanks us for the buying advice. His problem is that when he plays a DVD the brightness of the projector increases and decrease every ten seconds or so, though it depends on the movie. For example, A Bug's Life is much worse than 'Ronin'. He says he thinks he knows what it is and is probably something to do with Macrovision copy protection since movie don't behave this way when shown on TV. He wants to know how he can stop it happening? He says he realises that copy protection is there for a reason, to prevent people making tape copies from DVD, which is fair enough, but he is annoyed that he has paid good money for a lot of hardware that doesn't work properly!


Expert Reply             Pavlos has got it in one. The problem is almost certainly caused by embedded Macrovision signals messing around with the projector's automatic gain control circuitry. It shouldn't affect most TVs but VCRs, and video projectors respond by changing the picture brightness levels. It's something we've come across before but it varies from make to make and not all projectors suffer. There are two possible solutions, depending on the make and model of Pavlos's DVD player it maybe possible to disable the unit's Macrovision circuitry, companies that specialise in multi-region modifications often offer this as an additional service. We're duty bound to say that we cannot of course condone unauthorised tinkering and at the very least it will invalidate the player's warranty, but it definitely works. The second possibility is an external device. There's a group of products sometimes sold as 'video enhancers' but known generically as Macrovision 'Busters'. Some work some don't and changes to the way Macrovision is applied to the original recording can render some of them useless. It's all a bit of a gamble and we wouldn't want to recommend a specific make or model but if Pavlos has an Internet connection he should turn up some useful information by typing 'Macrovision Buster' in the search field of most search engines.  We've also heard that passing the video output from the DVD player through a video amplifier or AV amp with video feed-through sometimes works but the bottom line is that there is no easy one-stop solution.



Name              Wayne Foster, via email                                                  

Kit                   Panasonic NICAM VCR, Yamaha E492 processor, Cyrus amplifier, Kef Q55 and Q85 front and centre speakers, Mission 735 rears

Problem            Wayne is on the brink of purchasing a DVD player and naturally enough wants to get the best possible results from the equipment he already has, his budget is approximately £700 to £800. He adds that he lives in a semi-detached house with his parents and unfortunately cannot use a sub-woofer with his system. He would like to have both Dolby Digital and DTS and is quite interested in the Pioneer 626, which has an on-board DTS decoder but has just come across the new Technics Dolby Digital/DTS stand-alone decoder. He wonders if this gives superior results compared with a DVP player with a built-in decoder?


Expert Reply DTS continues to generate a lot of interest despite the fact that Region 2 recordings are still desperately thin on the ground. It looks like staying that way for a while, in which case if Wayne plans to get hold of imported Region 1 disc he needs to be thinking in terms of a multi-region player. However, as a point of interest one of the format's most impressive qualities is its bass handling abilities and there's not much point putting together a system without a beefy sub-woofer. Without one it's unlikely Wayne will notice a lot of difference between DTS and Dolby Digital.


On the question of whether it's better the go for a DVD player with a built-in DTS decoder, or a separate decoder, the simple answer is that's as far as mid-market equipment is concerned there's really not a lot of difference. High-end kit is another matter and the separate route will yield the best results, but we're talking about a potential investment well above Wayne's proposed budget. The other problem is that situation is changing quickly it's hard to make specific recommendations. Panasonic and set the ball rolling with a DVD player with an on-board DTS decoder, swiftly followed by Pioneer and we have heard of several others are in the pipeline. We wouldn't mind betting that by this time next year DTS will add little or nothing to the cost of a player with a Dolby Digital decoder and hopefully by then there will be a worthwhile catalogue of R2 DTS material available. 




Name              Jim Nixon, via email                          

Kit                   Pioneer DV-626, Toshiba 3327DB TV, Philips S-VHS VCR   

Problem            When playing Region 2 discs on his seen year old Tosh TV Jim says his jaw drops, the picture is stunning but when he tries Region 1 movies on his modified player the picture shows a lot of 'shimmer'. The edges of text characters and the on-screen menus are jagged with herringbone patterning. This isn't too bad when he's watching a film, he says, but if he gets closer to the screen it becomes noticeable. This doesn't happen with R2 discs, even close up to the screen. His question therefore is, does this affect all TVs that can play pure NTSC signals or are R2 discs simply sharper?


Jim has a couple of other related queries. SCART 1 input on the TV allows for an RGB input. If he got hold of the correct lead would an RGB connection improve picture quality? And lastly, when the player was chipped for all region playback the Macrovision was disabled. Jim wants to know if he can now tape R1 DVDs if he sets the player to modified PAL output, so that the VCR will see a PAL 60 signal instead of an NTSC one?   


Expert Reply  The slightly ragged picture picture from Region 1 DVD is due to a combination of factors. There is no question that NTSC picture quality is inferior to PAL, to begin with there are around 15% fewer picture lines, resulting in less fine detail and the NTSC colour system is not as clean or stable as PAL. Although Jim's TV can display raw NTSC the video and colour processing circuitry is optimised for PAL. Using an RGB connection between the DVD player and the TV should result in a small but worthwhile improvement in picture quality, especially if he's using a composite video connection at the moment, RGB should also eliminate any herringbone patterning. We can't really comment on Jim's last question except to say that it is illegal to copy DVDs, so don't do it! 'Nuff said!



Name              Raymond Brand, via email                          

Kit                   Philips 6332 TV, Sherwood R925 AV Receiver, Panasonic A360 DVD player 

Problem            Whilst working through the initial settings on his A360 DVD player Raymond has been trying to adjust the levels for the front, centre and rear speakers, using the player's test tone generator. However, there is no test tone coming from any of the speakers, he says the player is connected to the Sherwood amplifier using a QED digital interconnect lead. The player is linked to the TV via an S-Video lead. He's nonplussed since Dolby Digital sound is coming through okay and cannot believe how good it is, compared with Dolby Pro Logic, but he's wondering if it would sound even better if he were able to set it up properly with a test tone.


Raymond says he contacted Panasonic and they told him that there would be no test tone output from the player because he is using the coaxial digital output. He wants to know if this is true, and if so, why not? Panasonic's help line went on to suggest that he could use a DVD demo disc to set his levels and delay times.


Expert Reply             Panasonic are correct but there's nothing particularly sinister about it. What comes out of the DVD player's coaxial (and optical) digital output is the raw audio datastream direct from the disc. Since it is unprocessed – that's the job of the Dolby Digital decoder in the AV amplifier – there is no way for the player to alter the levels. The demo disc suggestion is a good one, though they're not that easy to obtain. Various titles are available including one from Dolby Laboratories, intended for engineers though this is quite difficult to get hold of unless you're in the trade. Others, like DVD Spectacular, contain video clips music and test tones.




Name                          Danny Reddington, via email                    

Kit                               Thomson 3300 DVD player

Problem                      A Region 1 copy of Matrix is refusing to play on Danny's Thomson DVD player. It's the only disc he's had trouble with and want's to know if we can shed any light on the matter?


Expert Reply             Indeed we can. By coincidence we heard that copies of Matrix and Something About Mary are refusing to play on some Samsung DVD players, and it just so happens that Samsung badge engineer players for Thomson. The problem concerns hybrid discs, that contain both DVD video and PC data. These discs have extra content that can be accessed from a PC with a DVD ROM drive and it appears this is upsetting the player's transport firmware (DVD-709 and badge engineered clones). Samsung says its players have always been fully compliant with the DVD specs but this is a relatively new feature that is still evolving, and one which they support. It has moved quickly to rectify the problem and new models coming through the system have been upgraded. Owners of older DVD-709s can return their machines to dealers for a free firmware update. As far as Thomson is concerned, a spokesperson assured us that only a small handful of early machines are affected and all current models will work properly. If Danny and anyone else with a disobediant Thomson player takes their player back to the dealer from whence it came it will be upgraded free of charge.




PC users are accustomed to software 'Easter Eggs' but now the hunt is on to find them on DVDs. Easter Eggs are hidden features, those on PC programs usually consists of amusing little graphics displays, lists of credits or even games put there by the programmers. DVD Easter Eggs are in a similar vein and include mundane things like credits but there's also some real gems to be found, like extra clips, out-takes even entire musical soundtracks. One disc even has a sound file of the director telling you to stop looking for Easter Eggs and get on with something useful – we won't say which one that would spoil the fun. Most Easter Eggs can be accessed by selecting innocent looking graphics or icons in the disc's special features menu, others depend on more elaborate actions and finding Easter Eggs has become a national pastime in the US.   


Not all Easter Eggs make it across to Region 2 releases but it's always worth a look through the menus for unusual features. If you're feeling lazy there are several US Internet sites featuring lists of the latest Eggs, and how to find them. One of the best can be found on the DVD Review web pages, the address is: http://www.dvdreview.com/html/hidden_features.shtml



Ó R. Maybury 1999 1211



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

Copyright (c) 2005 Rick Maybury Ltd.