DVD player is a very complex and precise mechatronics product. In the long-term use process, some models will inevitably have some problems of one kind or another, and even fail to continue working, so good after-sales service is absolutely necessary. When buying DVD players, we should first choose products from large manufacturers with sound after-sales service system. In this respect, domestic models have obvious advantages. Therefore, in the case of similar performance and price ratio, we should not hesitate to buy domestic models, so that we can enjoy more reliable and faster after-sales service. Don't trust the dealer's rhetoric, or just buy those "three noes" fake and inferior products for the price difference of only 1 yuan, otherwise you will buy endless troubles instead of happiness and enjoyment. Therefore, good after-sales service should be the first consideration in purchasing all household appliances. No matter how good the product is, you can't buy it without after-sales service.
Second, look at the machine core
The machine core is the mechanical part of the DVD player, and it is the most critical part in the DVD player, which directly affects the normal use and life of the whole machine, and the most precious thing in the machine core is the laser head-abbreviated as the optical head. At present, there are basically four types of DVD players on the market.
the first type is a DUAL LASERS machine core with two laser heads. When the disc to be played enters, the disc reading mechanism first detects its format. If it is a CD or VCD disc, the laser head playing CD and VCD will be automatically selected to work; If it is a DVD disc, it is operated by the laser head that plays the DVD disc. The non-working laser head is automatically powered off and is in a "rest" state. The best thing about dual laser heads is that they can read CDs? R or CD? RW disc has good disc reading ability and long service life, but its disadvantages are complex structure, high cost and high mechanical failure rate. Early Sony DVP? S7, Pioneer DV-9, domestic Dihe DK-32SA, DK-32TA, Jinzheng DVD? N926、DVD? N99、DVD? N9618, Amoi DVD－858B, BBK DVD? AB93K, Desai DS-2, DS-21, DS-22, Wonderful DVD－8A, etc. adopt this kind of dual laser heads.
the second type is a DUAL FOCUS machine, in which there is only one laser head. It uses a dual-focus programming lens. When the disc to be played enters, the laser head sends out different laser beams to automatically detect the disc, and then automatically selects the corresponding focus point to read the signal according to the detected different disc specifications. That is to say, the single laser head of the dual-focus mechanism generates two focused light spots with different focal lengths at the same time, one of which focuses on the CD track and the other focuses on the DVD track, so as to play CD, VCD and DVD discs respectively. This machine core has simple structure, high reliability and low manufacturing cost, but the service life of the laser head is shorter, and a single laser head can't read CD? The information on R, DVD models with single laser head and machine core are also cheaper. Matsushita took the lead in developing the "double focusing lens", including DVD-88 CMC, DVD-89 CMC, Hongtu GK-56, GK-58, GK-62, and Jingechuan Valley DVD? AV81G, Skyworth DVD－45, DVD－65S, Malata DVD? Domestic models such as N98 have adopted this Panasonic single laser head movement.
the third type is a DUAL LENSES movement, and there is only one laser head in the machine, so it is also a single laser head movement. There are two lenses on the laser head, one of which is used to play CD or VCD, and the other is a special lens for playing DVD. The dual-lens mechanism uses liquid crystal shutter switch to switch different lenses. This kind of machine core is easy to track accurately, but because of the double lens structure, the laser beam power must be increased, which affects the service life of the laser head, and the mechanical failure rate will be higher because of frequent lens replacement. The dual-lens movement is Toshiba's original technology, which is adopted by its SD-3 and domestic Amoi DVD－8156 models.
the fourth type is the dual laser mechanism. The dual laser mechanism still uses only one laser head, but it has two laser diodes installed in one laser head, one of which emits and reads CD, VCD or CD? R uses a laser beam of 78nm (nanometer) for the disc, while the other laser diode emits a laser beam of 65nm for reading the DVD disc. Therefore, this dual-laser DVD model can not only read the CD? R, the disc reading speed is faster, its structure is simpler, the mechanical failure rate is reduced, and the service life is longer than the above two kinds of single laser heads. Pioneer DV? 515, Tianlong DVD-5, Philips DVD57M, DVD612K, DVD718, DVD725, DVD931, DVD955 and other DVD models made in China, such as Konka D18K and KOS DVD－3, have adopted dual laser cores.
to sum up, it is difficult for us to arbitrarily say which laser head is superior. What kind of laser head is bad? Objectively speaking, these laser heads have their own advantages and disadvantages. However, you can never play a CD? As far as the practical function of R is concerned, a DVD player with a single laser head is basically incompetent, but this is not the only condition for choosing a DVD player, and other factors such as performance and price must be considered comprehensively.
it is worth mentioning that there are still some DVDs on the market at present. ROM is a DVD player assembled for the machine core, DVD? ROM was originally designed for computers, mainly to deal with CDs in cooperation with related computer software? ROM and DVD? Of course, the information on ROM can also be used to play DVD when using DVD playing software. On DVD? The models with ROM as the machine core are lower in stability, servo accuracy, reliability, disc reading ability and error correction ability than the above four models with special machine cores. But on DVD? The manufacturing cost of DVD player assembled by ROM is greatly reduced. Although it can normally play DVD players under normal circumstances, neither images nor sounds can be compared with DVD players, and it is difficult to obtain clear and sharp images and immersive sounds.
third, choose the format
DVD players have various formats like DVD discs and color TVs. At present, most DVD discs on the market are NTSC, and only a few are PAL. Moreover, most imported brand DVD players have no format conversion function, that is to say, when playing NTSC-based DVDs, the output signal is NTSC-based; When the DVD is played in PAL system, the signal of PAL system is output, and there is no conversion between them. This may be a shortcoming of imported DVD players or imported brand models. When they are connected to a multi-standard large-screen color TV, when the color TV is set to "AUTO", the color TV will automatically select the same standard, thus obtaining colorful images. The vast majority of domestic DVD players have the function of format conversion, which is another advantage of domestic machines. That is to say, the output signal of domestic machine can be set to PAL, NTSC or AUTO at will. After connecting them to a large-screen color TV, if the DVD player is set to "AUTO", the NTSC signal will be output when playing NTSC DVD, and the PAL signal will be output when playing PAL DVD. If it is set to "PAL", the output signal will be in PAL system no matter what kind of DVD is played. If it is set to "NTSC", the output signals are all NTSC. This brings great convenience to users who use the old single-standard color TV.
fourth, look at compatibility
the compatibility of a DVD player refers to its ability to play many kinds of discs. At present, the laser discs in the audio-visual market generally include CD, LD, VCD, CVD, SVCD, DVCD, HDCD and CD? R、CD? RW and DVD, etc. As we all know, all kinds of brands and models of DVD players are compatible with CDs, that is to say, they can play CD records. However, most DVD players can only play a few of the above discs. Such as PIONEER)DVL? 99、DVL? The discs that K88 can play are CD/VCD/LD/DVD, and their biggest feature is that they can play LD discs. The dvf-51 of kenwood and DAVIA of THETA can only play CD/DVD, which is really too few. Like Sony DVP? S7 and Toshiba SD? The discs that most imported models such as K31T can play are CD/VCD/DVD.
The compatibility of domestic DVD players is obviously stronger than that of imported models, even much stronger. This is because domestic models are developed and produced according to the actual situation in China, so they are more welcomed by consumers. Kim Jong DVD? N9168 is compatible with CD/VCD/CVD/SVCD/DVCD/CD? I/DVD, etc., odd sound DVD－41 is compatible with CD/VCD1? /VCD1? 1/VCD2? /VCD3? /SVCD/DVCD/MP3/Dr? OKO/DVD, etc., Konka D18K is compatible with CD/VCD/CVD/SVCD/CD? R/DVD, AEP-85 DVD compatible CD/VCD/DVCD/MP3/HDCD/CD? R/CD? I/DVD, etc. Skyworth DVD－65S is compatible with CD/VCD/CD? I/CD? R/SVCD/DVCD/DVD, etc. Some imported models can also play CDs? R or CD? RW discs, such as Toshiba SD-9 and Pioneer DV-515, can be compatible with CDs? R, and Philips DVD955, Tianlong DVD－5, Pioneer DV-525k, DV? K12 and domestic Desai DS-22 can not only play CDs? R and can read CDs? Information on RW.
what is a CD? What about r? It just uses CDs? R or CD? RW burner in CD? R the meaning of recording images and data on the disc. CD? R disc has the same dimensions as CD disc, and the way of recording data on it is the same as CD or VCD disc. CD? R disc can only be burned once, which is exactly the same as CD and VCD. People use video cameras to photograph the baby's growth, record meaningful events such as wedding celebrations and sightseeing, and then use CDs? R or CD? RW burner to CD? R disc, thus preserved forever. CD? R disc can use CD with MULTIREAD function on computer? ROM drive to read. It is worth mentioning that our common CD? There are three colors of R disc: gold, green and blue, so there are so-called "golden disc", "green disc" and "blue disc", among which "golden disc" has the best performance.
what is a CD? RW(CD? What about ReWriteable? CD? RW disc must use the CD used on the computer? RW burner to write, and can be written repeatedly, just like writing on the blackboard, can be erased and written repeatedly.
at present, most DVD players in the DVD market can't play CDs? R disc, can read CD? The model of RW disc is even smaller, which is really a regrettable event.
what kind of DVD player can play CDs? R disc player? CD? R only has a good reflection effect on 78mm (nanometer) laser. So, generally speaking, a DVD player with a single laser head that can only emit 65nm laser is difficult to play CD? R disc. For DVD players with dual laser heads and dual lasers, most of them can play CDs? R disc. To be sure, with the popularity of computers and CD? R and CD? RW burner walks into thousands of households and can read CDs? R and CD? There will be more DVD players for RW discs.
5. Choose all (zero) regional models
As we all know, when the DVD standard was formulated in 1996, at the strong demand of the American Film Association headed by HOLYWOOD and consumer electronics manufacturers, the international DVD alliance divided the world into six regions in order to protect its own interests: the first region-the United States, Canada and the East Pacific island region; The second area-Japan, Europe, West Asia, Arabia, Egypt, South Africa, Greenland; The third area-Hong Kong and Taiwan, South Korea and Southeast Asia; Fourth area-Central and South America, Australia, New Zealand, South Pacific islands; The fifth region-Africa, India, Central Asia, Mongolia and the former Soviet Union; The sixth district-Chinese mainland. The identification code is added to the DVD, and the area code identification mechanism is added to the DVD player. Only when the area code recognition mechanism of DVD player is consistent with the area code on DVD player can it be played, otherwise the machine will refuse to work. The first generation of DVD players did work like this, such as Panasonic DVD? This is the case with A3 and other machines. Because the vast majority of DVD manufacturers and consumers have always been strongly opposed to regional codes, coupled with the rapid development of DVD software and hardware technology. At present, the area code seems to be useless. However, most imported models or imported brands of DVD players still seem to be machines in a certain region (most of them are sold in the sixth region in the domestic market). And domestic amoi DVD－8156, DVD－8166, Kim Jong DVD? N926、DVD? N9618、DVD? N99, Desai DS-21, DS-22, Qisheng DVD－41, Gauss DVD－3, etc. all publicly show that they are full-area (or zero-area) DVD players that can play discs in various regions. Choosing these "all-in-one" models of global discs can greatly enrich the sources of discs. In fact, there are still many domestic DVD models that are also regional players, but they are just "still hiding half her face from us behind her guitar" without public declaration.
6. Choose a model with upgrade function
DVD technology is changing with each passing day, and no one wants the DVD player bought today to become a "chicken rib" after a period of time. In order to make the machine you buy keep up with the pace of technology, you need the machine with intelligent upgrade function. Hongtu GK-56, GK-62, Xinke DVD－858, DVD－83, BBK DVD? AB93K, Amoi DVD－8166, Philips DVD711, DVD781, DVD95 and other models have this intelligent software upgrade function. In order to add new functions to the DVD player, it is not necessary to open the cover, but also