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Discussion Starter · #1 ·
Ok. My setup is as follows:


Playstation 3 slim outputting HDMI to TV. From my TV (Sony EX500 LCD) I have analog 2 channel out to my Carat A57 mk2 amp.


I had it set at bitstream but when I switched to any lossless audio it would go silent.

Ok under settings I changed auto audio to manual and made sure to include DTS MA and Dolby True.

Still no sound. Then I changed it from Bitstream to PCM and now I got sound on DTS MA and Dolby True soundtracks. So I am guessing that now that the Playstation 3 slim is doing the conversion to PCM and sending it to my TV the TV is able to decode it to higher quality 2 ch via analog?

But can the DAC in the TV decode Lossless from a PCM signal?

I am certain that I can hear a clear difference between lossless and lossey. Voices sounds much more relaxed. Can somebody explain this mystery for me?
 

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First, some background: Movie soundtracks are mastered as multichannel PCM, which are quite large. Studios use data compression codecs to save space on discs. The PCM is fed into the decoder and compressed. The decoder decompresses it, turning out back into PCM. Lossless codecs restore all of the original PCM while lossy codecs permanently remove some of the original material.


When you set the PS3 to decode the soundtrack, it does the decompression and downmixes the multichannel track to stereo since TVs are two channel devices. All the TV does is the digital to analog conversion (DAC). What do you mean when you say the TV is decoding it to higher quality 2 ch analog? There's no decoding involved there. It's already been done by the PS3. The downmixing to stereo has already been done by the player, too. And the quality of the source is not controlled by the TV. It just converts the stereo PCM digital source to analog for output.


Perhaps you will now understand that your final question about the TV DAC decoding lossless from PCM doesn't make much sense. Lossless refers to the codec that was used to put the PCM soundtrack on the disc to save space. TrueHD and dts-MA are lossless codecs. The PS3 has already turned them back into stereo PCM and the TV just does the digital to analog conversion.
 

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Discussion Starter · #3 ·
Ok. Thanks. I didn't know my PS3 slim could figure out by it self to downmix the audio from 5.1 to 2.0 . This explains why I hear a difference. The PCM the TV is fed is of a much higher quality.


But a better DAC from PCM to anlog could make a difference I guess. Thanks.
 

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The PS3 doesn't figure it out on its own. In the HDMI handshake, the TV tells the player to send 2.0.


As for DACs, the general consensus is that there's little or no difference among them these days. You might want to try sending the analog output of your PS3 rather than the TV to see if that makes a difference you can hear.
 
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