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post #1 of 6 Old 11-27-2012, 06:05 AM - Thread Starter
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I understand why HDMI bitstream is more liked by people, but the truth is PCM is more advanced and true to the new HD DTS and Dolby formats. Here is the real problem, the audio advancements to day need to catch up. Yes it's true 2012 NOV. Bitstream is a comprest audio, that can decode the same HD formats as PCM, but does not give us true uncomprest HD audio. You may think what's the difference. Well the difference is PCM has a wider range of audio, it gives thicker sound and warmth to the tracks. On bitstream warmth and thickness on HD tracks are usually lost, because the compression of the audio can take away from the true sound that was put on the recording. The bitstream is usually liked by people more, because, if there is any kind of hiss or degradeing audio noices that have not been refined on the track. Bitstream will clean them up. The PCM will not make any compressing adjustments, It will give you the true sound that was done in the studio. It can be a good thing to have more clean sound, but the bad thing is you will lues that real true motion of the tracks. Example, a movie like Transformers and Inception have know hiss or noice issues, and can be heard beautifully on PCM. A movie like Batman Begins has big hiss issues and can be heard clearly on PCM, but will be covered up by bitstream. It reminds me when HD video did not look so good back in 2004. Blue ray and Hd Dvd had quite a challenge when they first were put to the true HDMI 1080i and 1080p test. Now HD sound has to meet that same challenge. So until the audio formats catch up completely, bitstream can be your back up. As for me I like the true definition of sound, even if it's not so clean, so I will stick to uncomprest PCM. I used a TX NR 609 Onkyo receiver and SKS 540 Onkyo Speaker set to listen to the difference between the Bitstream and uncomprest PCM. It is a THX certified receiver, not the best of the best, but it gets the job done when it comes to true uncomprest HD theater sound. Also note that your Blue Ray player could be a factor when it comes to true uncomprest PCM sound.
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post #2 of 6 Old 11-27-2012, 06:10 AM
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dear me... so much wrong information in one post...

- chris


my build thread - updated 8-20-12 - new seating installed and projector isolation solution

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post #3 of 6 Old 11-27-2012, 06:24 AM
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Originally Posted by ccotenj View Post


dear me... so much wrong information in one post...

+1! Reading that gave me a headache.

I don't need snobs to tell me how to think, thank you!
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post #4 of 6 Old 11-28-2012, 01:08 PM
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I don't think I've ever seen so much nonsense crammed into a single post before.

OP, do you truly understand ANYTHING about digital audio formats?
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post #5 of 6 Old 11-28-2012, 03:18 PM
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PCM is decoded audio stream.

Bitstream is transmission of compressed data. TruHD and DTS-MA are lossless formats.

DTS-MA converted at the player, transmitted to an AVR as PCM...


DTS-MA bitstreamed to the AVR, then decoded.

Bit for bit. Digital audio. No difference. Nada.
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post #6 of 6 Old 11-28-2012, 04:45 PM
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afaik bitstream is the player sending the digits directly to the receiver without massaging them at all. so an older Disney title with no HD but instead containing multichannel PCM would bitstream as PCM (over hdmi).

whether and to what extent lossy encoding systems are audibly different from the original pcm depends on a lot of factors. but afaik the most audible changes occur first in the highs, because they are the most data intensive.

but, op, i'm digging the new word "comprest" because it sounds like i get to chill out if i listen to a data compressed sound track.
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