Originally Posted by oky****
you're on your own with all that. its a very artificial and strained way of trying to concoct an argument to support a conclusion that you previously desired to justify. that type of thing is generally seen as disingenuous.
i'm not an expert myself, but every single thing i have read, other than your arguments, is in conflict with your conclusion.
it is generally acknowledged that pcm and dsd are different, although there are obvious similarities between digital processes. it think it is safe to say that your opinion has been considered and rejected by the experts [not that i am one of them, so what do i know].
i would simply note the obvious [and i believe others have noted it also]. what you consistently fail to address is the fact that dsd is all about taking one bit and simply documenting whether an amplitude increases or decreases. there is no attempt to document the value of the sample [amplitude] with that one bit.
The problem with this "fact", is it is not a fact, it is a misconception, what you have described is a delta converter, not a sigma delta converter.
Working with signals is one of the things I do, I started studying it over two decades ago, I've serviced audio hardware, I've developed audio and video compression codecs, I've worked on 3d sound algorithms, and I've developed a soft-synth that some people here may be familiar with. This isn't guesswork on my part.
anyhow, if you want try to establish some basis i guess you could write a paper and submit it to aes for consideration or something like that. have it peer reviewed, and see if the scientific community thinks there is any merit to your argument. short of that, making off-the-cuff statements seems improper. you should at least acknowledge in your unqualified posts that what you are stating is only your own theory and argument, and that it is not widely held [or held at all] by others.
If someone would like to send me some DSD files, I'll write a pcm converter for them... would that convince you that I understand what's in them? There's nothing to submit to the scientific community because nothing I've said is controversial, a sigma delta sample stream (be it one bit or 24 bit) is not a PCM of the original input signal, it is a PCM of that signal with an error compensating component (which is going to be much smaller in the case of the 24 bit conversion). From the DSP programmer's point of view this is key to understanding how to work with it, from the user's point of view it is key to understanding that DSD doesn't challenge Shannon-Nyquist in any way, understanding it requires a greater understanding of signals that the simplistic one that word with means accuracy and sample rate means bandwidth and never the twain shall meet (something which you are at least aware of I know), but it's not a different technology or set of concepts as some believe.
In normal conversation and descriptions however it is understandable and in many ways beneficial to refer to use the term PCM to mean non noise shaped PCM (the one everybody knows where when you look at the samples on the computer screen they look pretty much like the original waveform), and DXD, DSD, DSD wide etc to refer to those particular formats and the signal characteristics involved. It's like fruits and tomatos, normally when people talk about fruits they don't think of tomatos, you don't put tomatos in a fruit salad, tomato ice cream is probably something only Heston Blumenthal would think of, but sometimes it's important to understand that tomatos are actually fruits.
(Incidentally, I've stated this a couple of time in Bruno Putzey's forum in threads where Bruno has been active, and he's never disagreed with me, do you at least accept that Bruno understands about converters?)