Auzentech HomeTheater HD Preview: Bitstreaming True HD/DTS-HD MA

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• Jaybus - Friday, September 4, 2009 - link

  This is true. I think this should be a software option. It seems they limit bitstream output to 6.144 Mbs, which is the maximum allowed for DVD-Video. This only allows 16-bit 48 kHz sampling for 7.1 surround. Perhaps, with the exception of these high-end audio cards, it is the hardware itself that can't handle more than a 6.144 Mbs audio bitstream over HDMI? Makes the software more compatible with various HDMI implementations? License only allows for DVD-Video quality audio? Not sure.

• mczak - Wednesday, September 2, 2009 - link

  Err, there's no point in using "specialist" high quality hardware for decoding. This is a lossless format, so any decoder adhering to specification will in fact decode it to the exact same uncompressed data. D/A conversion will happen in the receiver anyway so it really doesn't matter where you decode the lossless format.
  But audiophiles might argue about "better bits" and whatnot whispering words like "jitter"...

• micksh - Wednesday, September 2, 2009 - link

  Thanks a lot for the article. The essence of the problem is very well formulated.
  
  This is exactly what I gathered from months of reading AVSForum. LCPM over HDMI provides you enough resolution for most blu-ray disks even if it is downsampled to 48KHz/16 bit. It is still lossless and can be provided by cheap video cards or motherboards. Not many disks have greater than 48 KHz sample rate and 24 vs 16 bit is like 114 vs 92 db detail level. The difference can't be heard in most environments anyway.
  
  Current Blu-ray PC players just can't get it right with bitstreaming so there is no need to pay ridiculous price for audio hardware. With release of SlyPlayer there will be no need to pay for crap software either.
  
  It is great that the article is appeared on such respectable site.
  
  One question regarding roadmap for motherboard bitstreaming over HDMI. I've heard opposite rumours - LPCM over HDMI can be discontinued because of the need to pay for license. Example - new ATI Radeon 5xxx series are going to lose LPCM over HDMI. Is it true about ATI?
  

• recon300 - Thursday, September 3, 2009 - link

  I have to agree. Thanks for the writeup, the issues you highlighted definitely need to be addressed. Great article.

• Procurion - Wednesday, September 2, 2009 - link

  I beg to differ. In a movie room, one built for this environment and set up for it, there is a difference. $250 is high-end which is the emphasis of the article. Subsonics are one of the first thing to go in a compressed format and obvious when compared. There are a lot of people who remember and still listen to lossless-only music and recognize what we're losing when they are converted to what the industry tries to pass off as "indistinguishable" differences in a less than full reproduction.
  
  In essence, you can't HEAR the difference, you FEEL the difference. Subsonics and ultra high frequencies can't be heard, true. They are felt.

• snarfbot - Wednesday, September 2, 2009 - link

  it ultimately depends on your receiver and speakers right?
  
  compressed audio does clip the very low and very high frequencies, but most consumer level audio equipment cant even reproduce that part so you wouldnt feel it anyway, even if you could, which im not convinced of, at least in the high range. my mediocre speakers can reproduce painfully high frequencies as it is.
  
  also a good sub can only do around 20hz at best anyway, which is covered just fine by regular dvd's.
  
  so i cant really see what your missing, unless you are talking about bass shakers, you know the things that physically shake the chair your sitting in, which also work just fine with regular compressed audio.
  
  my particular ass for example probably couldn't tell the difference between standard and high definition vibrations.
  
  lol

• LTG - Wednesday, September 2, 2009 - link

  "you can't HEAR the difference, you FEEL the difference. Subsonics and ultra high frequencies can't be heard, true. They are felt."
  
  I'm not that confident in your ability to "feel" ultra high frequencies.
  
  Are you sure they can do anything other than give you a headache or upset your dog?
  
  
  
  

• Fallen Kell - Wednesday, September 2, 2009 - link

  "I'm not that confident in your ability to "feel" ultra high frequencies.
  
  Are you sure they can do anything other than give you a headache or upset your dog?"
  
  There were several scientific studies on just this subject, and in all of them the answer was yes, we do interpret many of the frequencies that we can not audibly hear. Multiple studies in the infra-sonic frequency ranges have all produces extremely high correlation that humans most certainly do detect infra-sound and interpret it. The high frequency results have not been studied as much, but the studies that I have seen have all shown that there is a very large percentage of people do somehow detect the frequency ranges (one particular study had subjects listening to music which contained a clipped frequency range and music where those clipped frequency ranges were still intact and brain scans were taken during the time. The music with the full range frequency showed much more activity in the brain, which showed that even though the frequency ranges were outside normal audible range, the brain was still interpreting the frequencies).

• jigglywiggly - Friday, September 4, 2009 - link

  Just get a ps3 and put linux on it, rip it to a smb windows computer. No encrpytion if using anydvd + way freaking easier.

• MrPoletski - Wednesday, September 2, 2009 - link

  It's more than that. You brain identifies the sound as a guitar sound, so you hear a guitar sound - the missing frequencies be damned. As far as you brain is concerned the missing frequencies are just distortion and will require your brain to do a little more work to decipher that it is a guitar sound. But in the end, you will always hear the guitar.
  
  That runs with the idea that you dont see and hear the things around you. You see and hear the sights and sounds your brain believes to be around you based on the input it gets from its ears and eyes - i.e. it's interpretation of that.
  
  Having lossy formats wont sound any worse until you have heard the real recording and even then, the difference will be far more noticable ion the experienced fatigue from listening to the music for a length of time.
  
  A tinny radio turned up too loud will tire you out if you are trying to listen to it, a high end hifi would not. In fact, it would be a joy to listen to. Try that tinny radio turned up too loud. You'll soon want to turn it off.