[avahifi]

This video is a bit technical, but very useful.

https://www.xiph.org/video/vid2.shtml

Frank Van Alstine

[Speedskater]

Yes, Monty has three good pages on xiph.

[rif]

Good stuff.

[avahifi]

I am kinda curious why there have been so few comments about my post herein.

The link to the video in my original post herein simply provides some very basic information regarding the digital recording and playback process and dispels some very basic mis-information about digital source material source material, such as it is composed of "stair-step" data.  NOT!

Thousands and thousands of hits about what obscure capacitor sounds better, and two responses to this post.

Oh well.

Frank Van Alstine

[rif]

It's a lot easier to sway opinions than it is to control the facts.  I think that people always have, and will continue to believe what their friends and peers believe. It's just now we are so large a society, you can find a group of friends and peers that believe what you yourself want to believe - we find like minded people to talk with.

Example: if I were to say that the Earth is flat, is that a true fact, a false fact, or opinion?  The answer is that it depends on when its being asked ...  a long time ago it was a true fact (based on their current state of the art science), after that it was an opinion of a smaller group of people that is it round not flat (based on some new facts), and today it's a false fact (based on our current state of the art science).  So what is fact and opinion can change through time, and that loophole leaves room for debates on wires, capacitors, fuses, binding posts etc.  Healthy debate is good.

Sorry for the rant, had to get it out.

[Davey]

I am kinda curious why there have been so few comments about my post herein.

Makes you wonder, doesn't it?

The "....very silly indeed...." article was mentioned in the HiRez Music Circle awhile back and was immediately dismissed as "total crap" by some of the folks. 

Cheers,

Dave.

[NIGHTFALL1970]

Frank,
I think I can guess why so few comments.  I can't play the video. Not on my Mac at home, nor on my PC at work. It asks me to download a different browser like Firefox or google chrome first, something I am not willing to do.  It won't even play on my iphone. Maybe that's why most people are not commenting?

[plaf26]

Example: if I were to say that the Earth is flat, is that a true fact, a false fact, or opinion?  The answer is that it depends on when its being asked ...  a long time ago it was a true fact (based on their current state of the art science), after that it was an opinion of a smaller group of people that is it round not flat (based on some new facts), and today it's a false fact (based on our current state of the art science).  So what is fact and opinion can change through time, and that loophole leaves room for debates on wires, capacitors, fuses, binding posts etc.  Healthy debate is good.

Sorry, rif, "the earth is flat" is not a fact and it isn't true--never has been and never will be (unless it gets hit by some earth-flattening force or object), even though a lot of people thought so once through no fault of their own.  They were just wrong that's all.  Science is about finding out the facts and the truth about digital downloads, wires, caps, fuses, binding posts (among other things) that have always been there and always will be.

[Speedskater]

I am kinda curious why there have been so few comments about my post herein.

................

Frank Van Alstine

I have seen several threads on several different forums about this video.

So it might get confusing as to just where and when you should respond to what.

[rif]

Sorry, rif, "the earth is flat" is not a fact and it isn't true--never has been and never will be (unless it gets hit by some earth-flattening force or object), even though a lot of people thought so once through no fault of their own.  They were just wrong that's all.  Science is about finding out the facts and the truth about digital downloads, wires, caps, fuses, binding posts (among other things) that have always been there and always will be.

My point was that as science learns more, we need to revise what we thought were facts. Facts change and we need to embrace that. What is true today may not be tomorrow.  Personally I don't believe in exotic cables, etc and won't use them in my system

[floresjc]

Frank this was much appreciated from my end.

[Otis]

I am kinda curious why there have been so few comments about my post herein.

Frank Van Alstine

Having no training in electronics, his lecture is just another form of "because I say so", just like all the others out there. I can't distinguish truth from falsehood.

I suspect that's the case with most of us.

[avahifi]

I think that maybe one could consider the "information" coming from a trained engineer or scientist with decent credentials to be possibly on a bit higher plane than that from a purveyor of $10,000 a pair interconnect cables.

Go back to the home page of the producer of the video link above and try learning a little about electronics.  The basics are not all that hard to understand.

Frank

[Napalm]

The basics are not all that hard to understand.

I do understand more than the basics and here are some points where I disagree with him:

1) he says that 20kHz is the human hearing upper limit in frequency (implying that anything beyond that doesn't make any difference - this was disproved by some tests)

2) he is concerned only by amplitude omitting phase from the discussion

3) he refers to the Nyquist-Shannon theorem omitting to mention that the proper way to reconstruct the original signal from samples is by summing sinc functions for all samples, which is not exactly what a DAC followed by a low pass filter will do

Otherwise I'm not into 10k cables either.

[Brett Buck]

I am kinda curious why there have been so few comments about my post herein.

The link to the video in my original post herein simply provides some very basic information regarding the digital recording and playback process and dispels some very basic mis-information about digital source material source material, such as it is composed of "stair-step" data.  NOT!

Thousands and thousands of hits about what obscure capacitor sounds better, and two responses to this post.

     Like others, I cannot play the video so I can't comment on it (and the little computer nerds living in their mom's basement and putting together web pages like lecturing people on their browser choice...).
   
    I have seen many cases on various hobby forums, that straightforward accurate technical information rarely gets a blip, and highly-opinionated gibberish brings everyone out of the woodwork. I prefer to think that clearly stated truth leaves no room for comment. I know that's probably not the reason, but I like that explanation better.

    Brett


p..s  OK, I watched the video (I know more about computer processing than little computer nerds living in mom's basement...) and while annoyingly presented, it's accurate.  I am not at all surprised that the audiophile world and the "hi rez" community do not care for it, I know it's right but I found the presentation a little smug. And given that the state of most audiophile analysis involves invoking wizards and demons, special incantations, and severe psychiatric issues, of course it's not going to go over too well. In any case, no one with their egos invested in various pet topics like this, and that have expended endless dollars and endless hours blathering on in public about how their system "reveals the composer's hidden inner message", of course they are going to react poorly and discount it.

    BTW, while the exact solution is summing up an infinite number of sine waves, in practice you only need a few of the terms to get within tiny fractions of a percent. We have typically defined infinity as 10 for professional purposes.

[rcag_ils]

I can't watch it because my browser won't open it and I don't need another browser, but I'll take your word for it.

PS, it's wrong to force another browser on others.

[Otis]

.

[Brett Buck]

I can't watch it because my browser won't open it and I don't need another browser, but I'll take your word for it.

PS, it's wrong to force another browser on others.

   It's a computer weenie notion to promote their dead format getting into the HTML Standard.

    Brett

[Napalm]

p..s  OK, I watched the video [...] and [...] it's accurate.  [...]
    BTW, while the exact solution is summing up an infinite number of sine waves, in practice you only need a few of the terms to get within tiny fractions of a percent. [...]

Accuracy implies mentioning the errors - including those given by using a finite number of samples. He ain't doing that, everything is just "perfect" in his presentation. 

And the real reason the signal is not a ladder at the output is the presence of a low pass filter there. Any rectangular signal will stop being rectangular after going through such filter. Any mention of the effects of a filter on signal phase?

Trying to imply that it's because of the math behind sampling and not the low pass filter is rather disingenuous.

Here's what happens without the filter:

http://jeelabs.org/2011/12/04/generating-sine-waves-with-dds/

it's a ladder all day long and a pretty ugly one.

And here's another presentation that was already mentioned on Audiocircle:

http://www.youtube.com/watch?v=1CkyrDIGzOE

done by the CTO of a company manufacturing DAC integrated circuits. They would definitely know if the signal at the output of the DAC is a ladder or a sine wave, don't you think so?

Coming back to the presentation on xiph.org, from my POV the guy there, in an attempt to make things more simple and convincing, lost credibility.

[dB Cooper]

Frank, in your discussion of the original Dyna ST-70 in your Audio Basics newsletter years ago, you went into great detail about how the "standard" testing process missed major non-linearities in the square wave performance of the amp even though the square wave output looked just fine on a scope. (Presumably any remotely credible modern amp could do at least as well on the same test.) And many other discussions of problems that went undetected in IHF testing. Also your articles on the Bitstream type DACs and their test (vs. "musical") performance come to mind. It sounds as if you are now defending testing procedures you criticized strongly in print for years. In other words, if non linearities can escape detection in an amp, perhaps there is something being missed here? Comments welcomed.

Nevertheless, it was interesting and informative. I love learning about, reading about, and hearing about audio reproduction, but when it comes right down to it, just gimme some music and I'm happy.