QUESTION ABOUT BITSTREAM OR PCM
Jul 13, 2020 at 2:43 PM Thread Starter Post #1 of 9

John Massaria

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I have a topping d90- it defaults to PCM
should I set my DVD CD Player to bit-stream or is PCM correct?

Ok I had my D90 for a few months- LOVE it. But I had a quick question regarding PCM when using my disc player- I always thought bitstream is what you want not PCM so why is this DAC set to PCM when using COAX- isnt that just resampling the crappy DAC in my DVD spinner? Thanks for any and all answers... I know PCM is uncompressed audio but isnt it being handled by the CD PLAYER and then resampled by D90 or am I crazy
 
Jul 13, 2020 at 2:55 PM Post #2 of 9
I have my blu-ray player set to PCM. It's easier because then it handles all the different formats in the player and hands it off to the receiver as plain vanilla PCM. But it probably doesn't matter. Whatever works.
 
Jul 13, 2020 at 4:43 PM Post #3 of 9
should I set my DVD CD Player to bit-stream
Isn't bit-stream another name to 1-bit Delta-Sigma modulation data? I don't know if that's what it means in this context. Also, bitstream can be raw PCM in its binary values with no header to identify its container (I guess?).
 
Jul 13, 2020 at 5:33 PM Post #4 of 9
He means digital passthrough to use a separate DAC in a receiver.
 
Jul 13, 2020 at 7:06 PM Post #5 of 9
Not dac in reviver
It’s a topping d90 dac
So using the DVD player as a transport only
I heard bitstream is handing it off best to external DAC rather than pcm
 
Jul 13, 2020 at 8:02 PM Post #6 of 9
Yes, but there probably isn't any audible difference doing it that way.
 
Jul 14, 2020 at 5:16 AM Post #7 of 9
I have a topping d90- it defaults to PCM
should I set my DVD CD Player to bit-stream or is PCM correct?

Ok I had my D90 for a few months- LOVE it. But I had a quick question regarding PCM when using my disc player- I always thought bitstream is what you want not PCM so why is this DAC set to PCM when using COAX- isnt that just resampling the crappy DAC in my DVD spinner? Thanks for any and all answers... I know PCM is uncompressed audio but isnt it being handled by the CD PLAYER and then resampled by D90 or am I crazy
I'm also assuming that bitstream in this instance is how the term is used in video to mean " audio passthrough". Which is only relevant for some multichannel formats when the receiver doesn't "speak" the format. Then instead of passthrough, you set PCM and the DVD player will either convert the signal to PCM if it "speaks" it, or just pick another audio file on the DVD that happens to be in PCM or at least something the DVD player knows how to convert to PCM.
Your stereo DAC doesn't have any business with this, and the digital file on a CD is already PCM.
 
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Jul 14, 2020 at 8:08 AM Post #8 of 9
thank you
 
Jul 14, 2020 at 8:38 PM Post #9 of 9
To re-iterate, if your intent is stereo, PCM is usually the default and the highest quality for stereo. Bitstream has to do with passthrough for multichannel formats (such as Dolby Digital+ or lossless codecs). With HDMI you can pass multi-channel PCM from a blu-ray player. But bitstream doesn't decode the source codec and passes it to your multichannel receiver (advantage being receiver supporting newer formats or more channels).
 

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