Are you having an argument with yourself?? I've never mentioned delta-sigma dacs nor have I said anything about upsampling being part of a non-OS dac...
All I said was that by bypassing the oversampling on something like an AD1955 you can at least perform upsampling elsewhere instead and not rely on AD's on-chip algorithms.
Maybe your anger towards the non-OS concept has coloured your reading of posts?
"Gotcha" ??
I don't care about non-OS - I'm not into them at all. OK, I am open minded and would like to hear one because of the description of the sound.. But yes, how other people define THEIR non-OS dac is entirely up to them! Who are you to dictate ?
One would expect at least a little bit of avoidance of oversampling, perhaps that done on-chip..
Gotcha! This is not a technical forum! You have been wrong all this time.. and hence explains your attitude.
This is a DIY forum where all people - from the non-technical to the experienced technical - meet and discuss DIY audio in all it's forms from the non-techinical to the highly technical. And that includes subjective experimentation where no knowledge is needed (perhaps some basic safety helps..).
I'm sure there are plenty of purely technical forums about where you can meet only like-minded people, if that's what you're seeking.
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I had actually.. I went back to check I hadn't said something I didn't remember. I hadn't. People avoiding oversampling and ditigal filters happened before any notion of avoiding delta-sigma etc. People's experimentation with cutting some processing chips came first, including the personal experimentation of those who became Audio Note UK. The furthering of Audio Notes' philsophy - by this time, possibly could be called a marketing USP - came later, after non-OS dacs had been talked of. Again, no-one sets any "rules".
Your reply to a previous post, from the outset, appeared to be carrying forward an argument from somewhere else and seemed rather odd. You came in talking about "what most non-oversampling zealots" would say - indicates an internal argument and one I'm not party to (nor particularly interested in).
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Going to make one little exception to my last post and highlight the relevant parts of your post for you.
For the OP, and because each has its own signature, how about:
NOS (R2R and/or chip such as TDA1541)
Hybrid (ASRC+NOS)
Upsampling (ASRC+OS)
Oversampling (OS)
ASRC pure digital (DDX/FFX, & PCM-PWM-A)
Anything else?
I'm sure there are sub-categories too.
NOS (R2R and/or chip such as TDA1541)
Hybrid (ASRC+NOS)
Upsampling (ASRC+OS)
Oversampling (OS)
ASRC pure digital (DDX/FFX, & PCM-PWM-A)
Anything else?
I'm sure there are sub-categories too.
Not strictly true - there are filters which 'retain the original samples' - Schiitt makes a bit of a song and dance about theirs doing so. Of course there's nowt wrong at all about not retaining original samples because there's nothing special about them. Its just another one of those audiophile shibboleths 😀
It could very well be the reason why some prefer non-oversampling DACs without reconstruction filtering. Intersample overshoots could also very well be the reason why some prefer DACs without digital filters. At least this sounds less far-fetched to me than any theories involving audible ultrasonics, notwithstanding the Japanese Gamelan player experiment.
I am struggling to understand what is "philosophically .. wrong" with a filter which actually filters its input i.e. produces output which is different from the input; isn't that exactly what a filter of any type is supposed to do? However, if that is their rather strange view then I guess they have to go back to using analogue filters with all their problems - which produce output different from their input, like all filters.
You can't have private definitions of terms any more than you can have private versions of physics and maths - at least, not if you want to be taken seriously and have meaningful discussions with others.NATDBERG said:
In the specific case of the CDP-101 as grating as it was I dont' think letting more crud through would improve matters. As to NOS in general, tried it did not like it.
Yep. All consistant with what I've been saying.
Somehow you are reading between the lines and coming up with a meaning that fits your expectation bias, what you are expecting people to say. Hence the question about whether you're arguing with yourself..
In the context of 99% of people who talk about non-OS dacs, it's a hobbiest term! Of course any hobbiest can call what they do what they want. It's not a scientific term, nor is it a digital theoretical term. It's is how it is used in common parlance that matters. I'd say those coining the term originally would also be of that ilk, despite a certain amount of technical knowledge etc
It may well be discussed in digital electrical engineering and those people want to define it for their own purposes (whilst maybe missing its whole raison d'etre) but let's not confuse the needs for a definition. If you want one amongst friends, you can define it for that group. Others can define it for themselves and their groups too...
Its all vague in the world hobbiests.
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What is the point of using a forum to discuss something but then destroying discussion by inventing private meanings of words? If you want private words then perhaps a private forum should be used so you can just talk to your friends.
NOS is not just a hobbyist term. It has a meaning, which rules out certain types of DAC chip.
NOS is not just a hobbyist term. It has a meaning, which rules out certain types of DAC chip.
If someone in a thread mentions non-OS then ask them what they mean by it .. that is how people from different backgrounds get on with and understand each other.
It was mentioned by someone who wanted no overt oversampling process in their dac (for whatever reason). I think its valid to call that a non-OS DAC as they take the same measures to bypass oversampling as someone would have on a multi-bit dac as per many enthusiast pages around the net, e.g. as you would bypass a SAA7220 in many TDA1541 based dacs.
A flow chart of the dac would appear the same. only a knowledge of delta-sigma might then show some oversampling going on. You'd be welcome to point it out but I think unreasonable to then force someone to never ever use the term "non-OS" again 🙂
It was mentioned by someone who wanted no overt oversampling process in their dac (for whatever reason). I think its valid to call that a non-OS DAC as they take the same measures to bypass oversampling as someone would have on a multi-bit dac as per many enthusiast pages around the net, e.g. as you would bypass a SAA7220 in many TDA1541 based dacs.
A flow chart of the dac would appear the same. only a knowledge of delta-sigma might then show some oversampling going on. You'd be welcome to point it out but I think unreasonable to then force someone to never ever use the term "non-OS" again 🙂
Overt and covert oversampling ought to be equally avoided by someone who wants NOS. It would be daft to reject 4x oversampling but be happy with 16384x oversampling.
Ought to.. for you to make sense of it (and others to make sense of it).
I'd say that subjectivism (which is pretty much the basis of non-OS stuff) has no need to make sense if it's only about people listening.
Viewing subjective choices through objective eyes is always going to tie people in knots..
Calling something X when it is actually Y will also tie people in knots. Especially if X and Y are opposites.
That is exactly the case and that is why I did create my own digital filter for old R-2R DACs:
16x Digital interpolation filter - drive PCM56, PCM58, AD1865 and so on up to 768 kHz
Oversampling is important to create a proper brick wall filter in order to reconstruct the signal.
There is a common misconception in which some claim that NOS is how music was supposed to be played. You cannot be more wrong than that. NOS is no where near reproducing the original signal, but in fact it does bring a lot of unwanted frequencies into the audio band due to lack of the brick wall filter.
Digital filter doesn't come up with some fancy samples it "thinks" should be there. It reconstructs the signal in a mathematical way and for the given input there is only one possible outcome. If digital filter reconstructs the signal wrong and there is a deviation from the original signal it means that Nyquist requirement was violated during recording.
The following video (from given timestamp) does in fact elaborate it further more:
YouTube
There are no stairs in an audio signal 😉
Another common misconception is that several signals can pass through the same points and digital filter "might" miss the original signal. Again, that is just wrong and everything is explained within the above video with a fancy painting:
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