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Measurement of R2R DAC

amirm

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If you had opened the link you would have seen that it wasn't a review, but a very interesting article about the two different technologies
Interesting? What does interesting have to do with anything? Where was a proof point with controlled listening test to demonstrate the truth there?

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Where is the proof point of that? And what is that "might" statement about? He does or does not know that is the case?

There is no there there. That kind of write-up might impress folks in an audiophile forum where people understand much less than he does.

In this site, we go by what we can prove, not what we believe. Measurements are repeatable and provable facts. Speculation like above is neither.

I mean did you really read statements like this and thought it was interesting?

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Remove what noise? Dither? Author is welcome to capture audio in 24 bit format without dither and tell us it sounds unacceptable. Even in 16 bit it will be very hard for him to hear effect of dither let alone become unacceptable.

Sure, if you are dealing with 8 bit audio, you absolutely need dither. But then he claims dither doesn't work because the brain doesn't average noise to hear its benefit. Which case is he trying to make?
 

DonH56

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"impenetrable math"... "tech writer by trade"... Focused on what area in his writing? The tech writers with whom I have worked over the years tend to pick up a fair amount of understanding of the articles they write, and the better ones work to gain a technical understanding of what they are writing. Why quote an authority with no expertise on the subject?

There are gobs of resources about data converters at a high lay level that anyone who has had HS math should be able to understand (some on this very site ;) ). But it may take some reading and thinking... Scientific American I always found interesting but had to work through the jargon for anything not in my field (and some that were; for a short while I actually understood aleph-one vs. aleph-null and the infinity of the continuum, and even had a decent understand of mitosis though been a while since all those pre-med courses).
 

gvl

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And that's exactly why you need to have DBT as a basic control.

Yes, but it only tells that there are no big differences that our brain can perceive in a short test. Take a stick and hit yourself moderately to be just under the threshold of pain, than keep hitting yourself in the same spot with the same amount of force, I guarantee that after several hits you will start to feel real pain, the stimulus is the same yet the perceived effect is different. I think this effect can be applied to our hearing as well, in a short DBT test the brain can't pick up small differences but they have compound effect in long listening sessions.
 

DonH56

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Yes, but it only tells that there are no big differences that our brain can perceive in a short test. Take a stick and hit yourself moderately to be just under threshold of pain, than keep hitting yourself in the same spot with the same amount of force, I guarantee that after several hits you will start to feel real pain. I think this analogy can be applied to our hearing as well, in a short DBT test the brain can't pick up small differences but they have compound effect in long listening sessions.

Don't buy the analogy but then again don't expect anyone will care what I think about it. However, regarding the bolded sentence, IME experience the opposite tends to be true. And I have certainly done long-term tests that found all sorts of wonderful things, then switching back to the original component revealed the same wonderful things were there all along. A new piece of gear tends to sharpen our focus on looking for differences and we (or just I) often find them even if they aren't really there. "Last night I saw upon the stair, a little man who wasn't there..."

Edit: The ending couplet of the poem may also be relevant: "He wasn't there again today; Oh, how I wish he'd go away..."
 

SIY

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Yes, but it only tells that there are no big differences that our brain can perceive in a short test. Take a stick and hit yourself moderately to be just under the threshold of pain, than keep hitting yourself in the same spot with the same amount of force, I guarantee that after several hits you will start to feel real pain. I think this analogy can be applied to our hearing as well, in a short DBT test the brain can't pick up small differences but they have compound effect in long listening sessions.

There's nothing limiting you in time for DBTs.

And of course, there's lots of experiments with long term listening that didn't show any increased sensitivity- and often the opposite. For example, in a rapid switching DBT, I can hear a 0.3dB difference which is quite small. Give me two boxes to live with long term with that amount of gain difference and I would bet that I wouldn't be able to tell you which is which.

Basic controls are basic.
 

solderdude

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The reason why I think this reasoning is flawed is because I have fooled myself a few times.
Long ago when I was still in my mostly subjective phase I had a switch (on the rear of a pre-amp) which switched between 2 internal circuits.
One with poor opamps and a bunch of electrolytic caps and tantalum (without DC bias) in series with the audio path and no decoupling caps and one with a (back then) expensive 'audiophile' opamp that was DC coupled and had compound decoupling.
I used it to show folks the difference between these 2 circuits (always telling what was used of course as I wanted to be honest) and everyone could hear it.
I always set it 'good' after the demo.. turned out not always though.
On 2 occasions I had been listening to the 'poor amp' for months not knowing it was in that position, being sure it was in the 'good' position.

If the 'long exposure' thing would exist I would have picked up on it. The long exposure 'trick' works ONLY when one knows what one is listening to.
 

fabien32

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How would he know what use his subjective opinions are to you?



Are you perhaps typing on a phone? That sentence doesn't make sense.

i am. and on top of that i am not a English native speaker (from israel)
 

fabien32

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Maybe you should ask someone who really understands the science (unlike the author) read it for you and tell you all that is wrong there.

SNR measured over 1 second? Who says?

Switching is bad in delta-sigma? How about switching in R2R?

Dither doesn't work? Really? There are dozens of demos on Youtube showing how dither works wonderfully and your ear doesn't need "1 second averaging" to hear its benefits.

And who is the author? I searched for Lynn Olson everywhere. I can't find a bio. Do you know if he has proper signal processing experience? If not, why on earth do you trust what he says? Did you not note things like this?

View attachment 33356

Pay attention to the name of this forum: Audio Science Review. We have membership here who actually knows this topic and has practiced it. And you tell us to read something written for audiophiles to believe?

Don't put your guard down because you like the message. Pay attention to where something is published. And by whom. Above all, don't print a page from the Internet to show to your doctor to tell him you know more because you read that. :)

Back to your statement, our measurements aim to determine if a DAC does what it is supposed to do: convert digital samples faithfully to analog. That is all it is supposed to do, and all it can do. It doesn't know what music is. It doesn't know noise. It doesn't know anything. All it is given is a sequence of numbers to convert to analog. Our measurements feed it numbers and determines if what comes out of the other side are the same or different.

Furthermore, when we see deviations, we have detailed data in the form of spectrum we can use with psychoacoustics to determine audiblity. No hand waving here.

Last but not least, what you state is the latest talking point about R2R. It used to be that people were told that these are the most accurate DACs. Many people buy them because they think that is the case. To the extent our measurements show otherwise, we dismiss with that marketing myth.
hi there, Thanks for taking the time, much appreciated. so you say that r2r has nothing special? i am asking because i heard few devices that where amazing
 

SIY

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hi there, Thanks for taking the time, much appreciated. so you say that r2r has nothing special? i am asking because i heard few devices that where amazing

That's the hazard of evaluating sound without limiting it to ears-only.
 

DonH56

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R2R DACs (which more than likely are not truly all R2R; the MSBs are typically unary to improve matching and linearity) typically have larger switching glitches and lowered linearity compared to delta-sigma designs. This can add low-level noise (and high-level, in the case of some switching glitches if not countered by an output T/H or some other means) and distortion that may sound pleasing to some. Like adding harmonic distortion and raising the noise floor in some other designs, the net effect may be more pleasing to some ears, though it is adding distortion not in the source. But I suspect a lot of the difference among DACs is the output buffer and anti-imaging filter rather than the DAC itself.

FWIWFM - Don
 

Julf

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Julf

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That's the hazard of evaluating sound without limiting it to ears-only.

Or he might prefer the noise and distortion...
 

amirm

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Here is a bit on audibiilty
hi there, Thanks for taking the time, much appreciated. so you say that r2r has nothing special? i am asking because i heard few devices that where amazing
I have tested a number of them including careful listening tests and no, I hear nothing special in them. You have to do a proper AB test with levels matched and blind. Once you do that, whatever people think is special about them, somehow goes out the window.
 

amirm

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i am. and on top of that i am not a English native speaker (from israel)
Ah OK then. In native English your message was very strong and confrontational. I assumed you meant it that way but if you are not a native speaker, then that could be a translation issue. So sorry for my strong reply back. :)
 

Julf

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Ah OK then. In native English your message was very strong and confrontational. I assumed you meant it that way but if you are not a native speaker, then that could be a translation issue. So sorry for my strong reply back. :)

We have to remember that it is often not just the language, but different cultures have different standards for directness, politeness etc. - what might sound rude to an English speaker might be normal conversation for, to pick an example, a Dutch speaker (known for their directness).
 

Juhazi

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Strange fight about subjective vs. DBT objective vs. measured again. I value measured highest, subjective comes second. Fortunately I can't hear differences in (adequate measuring) cables, dacs or amps, only with speakers!

It should be OK to express subjective preferences even here at ASR, like fabien32 did, without fearing to be blamed as a stupid person.

( English is my second language of four, learned at school)
 

solderdude

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Subjective preferences are perfectly fine to express as long as one doesn't express the findings as actual facts because one 'hears this or that clearly' or is 'so clear that blind tests aren't even needed'.

My experience mirrors that of Amir.
A well executed R2R (or derivative) with proper reconstruction filter is indistinguishable from a well executed (with a proper filter setting) DS DAC in a well performed blind test.
The 'magic' happens inside the head and is far from solely determined by the used technique but much more so based on 'human variances'.

These same well constructed DACs may well be perceived as different sounding when not level matched or when 'evaluated' sighted or in 'long term'. That has a different reason than the actual implementation of the used parts though.

That said, poor implementations of reconstruction filters or filter-less DACs can audibly (and measurably) differ from well implemented designs.
Both in well performed blind tests as 'subjectively'.

As these days filter-less NOS R2R (44.1/48) is the rage these actually can sound different. Some even prefer it.
Nothing wrong with preferring something like that... just don't say it is better. It arguably is NOT better at all. Just preferred by some.
 
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Sal1950

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It should be OK to express subjective preferences even here at ASR, like fabien32 did, without fearing to be blamed as a stupid person.
You can read subjective reviews anywhere, in any language.
But here you must expect to be questioned on the conditions under which you came to your impressions.
Did you use a bias controlled listening procedure or just your imagination?
 
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