DVD players and THX decoding?

Discussion in 'Blu-ray & DVD Players & Recorders' started by John Watts, Jan 21, 2005.

  1. John Watts

    John Watts

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    Hi all,
    Something crossed my mind today,

    I know there are quite a few THX badged DVD players out there but will any of them actually decode THX to your amp?
    That would be a tempting feature.

    Cheers for any replies,
    John.
     
  2. KraGorn

    KraGorn
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    I thought THX was a spec. for playback characteristics rather than a coding technique. Am I wrong?
     
  3. kumamoto

    kumamoto
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    THX is just a technical standard for picture and sound and not DECODABLE technology like Dolby Digital or DTS.

    A DVD or Amplifier carries the THX logos once it is submitted to THX for Certification which obviously carries a small fee.

    Many manufacturers eschews such certification for real tangible benefits like keeping the cost of the kit lower, which makes a product more attrractive to punters.

    Many non THX Hardware perforn upto THX standards and sometimes even better.
    Some manufacturer insists on such certification on thier kit to justify their hefty price tags!!
     
  4. Astaroth

    Astaroth
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    KraGorn, you are correct - THX is a series of standards rather than a coding technique/protocol.

    There are a growing number of THX standards in existance - a manufacturer can pay for their equipment to be tested against any number of the THX standards and if they pass the benchmark in one or more areas (and pay the licencing fee's) they can badge their equipment as THX certified.
     
  5. John Watts

    John Watts

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    It would be a good idea though if a manufacturer made a player that decoded THX i know most do DD and DTS. Granted usually not as well as a good amplifier.

    But say if you had a good amp with DD and DTS it would be a good way of "getting" THX if you like without buying a new amp.
    Just a thought but im sure there would be a market for it.
     
  6. Astaroth

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    John - you cannot 'decode' THX as it isnt a code - you could only decode DD or DTS to THX standard.

    The only problem with that would be that you then need to put the decoded sound through an amp and unless the amp is also THX certified then you would not definately get 'THX quality'.

    Of cause a large quantity of the top end manufactures do not believe in the likes of THX certification and think that their own name is enough to show its quality.
     
  7. KraGorn

    KraGorn
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    Thanks, I was wondering if I'd misunderstood.

    BTW, devilish nickname you have. :laugh:
     
  8. Zacabeb

    Zacabeb
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    It should be pointed out though that THX does involve processing as an option so to correct for the different speaker placement at home than in a movie theater. This is applied on top of the decoded signal, but is done only in processors and receivers/integrated amps.

    Aside from THX approved bass management which sends all bass content below 80Hz from all channels to the subwoofer, it involves three things:

    1.) Re-equalization compensates for the high-frequency emphasis in the front channels of movie soundtracks. Movie theaters and dubbing stages are built to follow the X-curve, which has a high-frequency rolloff, and the soundtracks mixed and sweetened relative to that. This leads to overly bright sound when sitting close to the speakers, so THX performs compensation for that.

    It is debatable whether this is desirable or not though, as it seems these days, correction for this is performed on many soundtracks already when remastering them for home release, meaning THX re-equalization is no longer applicable and just makes the sound muffled. After all, the vast majority of home theater products are not THX approved and do not have re-equalization built-in, so it's no surprise if studios are doing this correction for us.

    2.) Timbre matching, which does about the same thing for the surround channels as the front channels, also taking into account that unlike the multiple speaker arrays in a movie theater, the single pairs of speakers used at home produce a very direct sound. Again, high frequencies are attenuated to compensate.

    3.) Decorrelation, which detects if the surround content is monophonic and if so, applies a phase shift to the surround outputs to spread the sound, thereby widening the surround "sweet spot".
     

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