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Thoughts on DACs? - Page 3

post #61 of 833
Approximate is a fair word when talking about reconstruction filters as this is what they can only do unless you have infinite samples (or infinite time as described by both Nyquist and Shannon).
Bear in mind reconstruction filters in a DAC are working with individual components of the original waveform that are rectangular (step) shaped.

Cheers
DT
post #62 of 833
Quote:
Originally Posted by wrat View Post

for me it is for a PC so all the cd/dvd/universal players are not relevant

To answer your question either way would work as far as hdcd

Ah, well if you ever find a DAC with HDCD at a reasonable price it will probably rely on a lot of luck or searching.

Let us know if you do find one and good luck.
Cheers
DT
post #63 of 833
I asked: what *would* prove something to you?

Quote:
Originally Posted by wrat View Post

does that really matter?

Evasion noted.
post #64 of 833
Quote:
Originally Posted by wrat View Post

Why would you post Theory and Speculation and then run away?

Why would you badger him about that when you won't even say what constitutes proof for you?

You seem kind of selective in your logic.
post #65 of 833
Quote:
Originally Posted by tcb-player View Post

One doesn't "decide"; one hears.

When differences are subtle one does indeed 'decide', "yes, I think I do hear a difference". Or not.

Quote:


And most fundamentalists I know believe in science.

Fundamentalists don't believe in science, though they may accept some scientific facts as true, as long as they don't contradict their religion. They believe in revelation from a supernatural source.


Quote:


But getting back on-topic, the sound quality of any CD player or outboard DAC is very reliant on the final analog amplification stage, just like with a preamp.

Mainly, as Chu Gai notes, as regards output voltage, which can vary enough to give the illusion that one player sounds 'better' than another, when all it is is a little louder. In every other audible respect, CD players tend to be identical, though of course there can be exceptions (e.g., cheapo portable players).


Quote:


The better the unit, likely the better the output stage, so it's hard to separate the DSP sound from the overall.

This assumes that all increments of 'quality' are audible. They aren't. Beyond
threshold of audibility, output stages that 'measure' better sound identical.

There is typically no 'DSP' (digital sound processing) going on in a CD player, in the usual sense of the word.
post #66 of 833
Quote:
Originally Posted by DulcetTones View Post

Ah, well if you ever find a DAC with HDCD at a reasonable price it will probably rely on a lot of luck or searching.

All of the OPPO DVD players -- which range from $150 to $500 -- can decode HDCD, but if he wants an outboard DAC that does, the only one I recall is the old Musical Fidelity X-DAC. Maybe he can find one used.

Or he can use hdcd.exe (whcih I think has now been incorporated into nthe dbPOweramp ripper and digitally rip his HDCDs as 'decoded' files for playback.

Windows Media PLayer is another option, you have to activate '20-bit playback' optiion buried deep in one of its menus, and afterwards it will recognize and decode HDCDs in your computer's CD drive.
post #67 of 833
Quote:
Originally Posted by DulcetTones View Post

Approximate is a fair word when talking about reconstruction filters as this is what they can only do unless you have infinite samples (or infinite time as described by both Nyquist and Shannon).
Bear in mind reconstruction filters in a DAC are working with individual components of the original waveform that are rectangular (step) shaped.

Cheers
DT


Approximation is a fair word for any audio repro medium. All audio reproduction involves 'approximation', including everything from Edison cylinders to analog tape to LP vinyl to 24/192 digital. The key point is that digital approximation based on SHannon/Nyquist yields a replica that is measurable more accurate than any other method, if done properly.

Bear in mind that 'stairsteps' are a visual representation. They are not the signal itself.
post #68 of 833
Quote:
Originally Posted by tcb-player View Post


If you really wanted to hear the intended sound, you'd use an analog source.

You mean the master tapes? Because otherwise no analog source is giving you the 'intended sound' Certainly not LP!
post #69 of 833
Does hdcd.exe work for both downloaded songs and CDs, or does it require some messing around if wanting to store on the PC?

BTW I can confirm reactangular and stair-steps are the signal, try reading Nyquist Certain Topics in Telegraph Transmission Theory, a sinusoidal component is rectangular, thats why the reconstruction filter has to take that rectangular component and calculate the sine wave again.
Only after the reconstruction filter do you have a traditional sine wave again, its a fact that even modern telecoms has not been able to change.

So technically we are both correct

Cheers
DT
post #70 of 833
Quote:
Originally Posted by krabapple View Post

When differences are subtle one does indeed 'decide', "yes, I think I do hear a difference". Or not.

You're twisting the intent of the original poster of that comment. He meant that an audiophile will make an unjustified strategic decision to claim differences.

Quote:
Originally Posted by krabapple View Post

Fundamentalists don't believe in science, though they may accept some scientific facts as true, as long as they don't contradict their religion. They believe in revelation from a supernatural source.

The 2nd and 3rd phrases of your 1st sentence are correct, the 1st phrase contradicts that. And I'm not a Christian, but even I wouldn't characterize it that way.

Quote:
Originally Posted by krabapple View Post

Mainly, as Chu Gai notes, as regards output voltage, which can vary enough to give the illusion that one player sounds 'better' than another, when all it is is a little louder. In every other audible respect, CD players tend to be identical, though of course there can be exceptions (e.g., cheapo portable players).

Of course output voltages vary, so what? I'm talking about listening to the sound of the player, not specifically about doing matched-level blind tests. When I listen to a piece of equipment, I listen to it at a variety of volumes, and listen for tonality, colorations, brightness, fullness, soundstage presentation, spatial positioning, distinction of instruments/voices, naturalness of tone, etc. I use several different pieces/types of music, and I have sometimes spent hours/days listening.

I don't know why you need to declare that "CD players tend to be identical"; if I agreed, I'd already know it, and if I didn't agree, then why would it matter to me?

Quote:
Originally Posted by krabapple View Post

This assumes that all increments of 'quality' are audible. They aren't. Beyond
threshold of audibility, output stages that 'measure' better sound identical.

True, but again, so what? Is someone disagreeing with you on this?

Quote:
Originally Posted by krabapple View Post

There is typically no 'DSP' (digital sound processing) going on in a CD player, in the usual sense of the word.

Well in the specific sense of the word, as I described in detail, the hi-bit reconstruction I spoke about is performed with a bank of Motorola DSP chips, in some of the brands of players I mentioned.
post #71 of 833
Quote:
Originally Posted by krabapple View Post

The key point is that digital approximation based on SHannon/Nyquist yields a replica that is measurable more accurate than any other method, if done properly.

Yes. That is entirely correct.
post #72 of 833
Quote:
Originally Posted by tcb-player View Post

The 2nd and 3rd phrases of your 1st sentence are correct, the 1st phrase contradicts that. And I'm not a Christian, but even I wouldn't characterize it that way.

Actually, I would never use the phrase "...believe in science...". Science does not require belief, only proof.
post #73 of 833
Quote:
Originally Posted by HaroldTheBarrel View Post

Actually, I would never use the phrase "...believe in science...". Science does not require belief, only proof.

I've asked this before and I'll ask it again: what is your background, education, and expertise which makes you an authority on these lofty topics? By your own admission, you said "the only qualification I have is ears". Why can't we ever seem to have an adult-level discussion without being "corrected" with these childish bumper-sticker-grade platitudes? In my personal experience, people who are comfortable with the application of science are never the ones declaring "science!" at every turn.

For the sake of humanity, take a chill pill ... maybe put on some music.
post #74 of 833
This is going exactly like the previous thread that was locked.

I might as well point to these again as some seem intent on saying the usual vague facts.
http://www.mother-of-tone.com/cd.htm
Article is correct, no-one showed anything wrong last time. Apart from some vague comments as usual.
In other words those who say you end up with a perfect sine wave are wrong.
It seems for some reason there are a few who decide to talk about CD and say its a sinewave and yet do not understand the significance of the rectangular sinusoidal component.
This is shown in the above link, you only end up with the sine wave after the reconstruction filters work their logic on the rectangular sinusoidal components shown in the URL.
Also the URL is good as it shows some other challenges with sine waves and PCM.

Anyway, does anyone know if the HDCD.EXE works with downloaded sources or just for CDs?
I know a different program requires messing around to use anything but CDs.

Wrat, I even tried to think of CD players with input so you can use their DACs, and I cannot think of a reasonably priced one that has an input and HDCD.

Cheers
DT
post #75 of 833
Quote:
Originally Posted by tcb-player View Post

I've asked this before and I'll ask it again: what is your background, education, and expertise which makes you an authority on these lofty topics? By your own admission, you said "the only qualification I have is ears".

That comment was in reference to the details of the circuitry in audio components. I teach math and science (primarily physics, occasionally chemistry and/or biology.) I have multiple degrees, and have read enough to qualify for several more.

My comment about science was not a "platitude", but simply the truth. Science is not about belief, it is about provable facts. That is the primary thing that distinguishes it from religion (and audiophilia.)
post #76 of 833
Throughout all your evaluation TCB, how do you deal with bias control?
post #77 of 833
Yes, DT, you and I had that misunderstanding. I certainly looked and look at it from the POV of after the reconstruction filter. That's why with NOS DAC's, you get a stepped sine wave because they just leave that out. Square waves though look pretty square.
post #78 of 833
Quote:
Originally Posted by Chu Gai View Post

Throughout all your evaluation TCB, how do you deal with bias control?

I believe I explained it in my earlier post - what specifically did I leave out?
post #79 of 833
Quote:
Originally Posted by Chu Gai View Post

Yes, DT, you and I had that misunderstanding. I certainly looked and look at it from the POV of after the reconstruction filter. That's why with NOS DAC's, you get a stepped sine wave because they just leave that out. Square waves though look pretty square.

NP and sorry bud my comment was not directed at you.
Your comments fit within discussions and I can understand our differences, its some of the others I get a bit frustrated at.
Hope your having a good friday so far, bloody p£ssing it down with rain over here, booooo.

Cheers
DT
post #80 of 833
Quote:
Originally Posted by HaroldTheBarrel View Post

Science is not about belief, it is about provable facts. That is the primary thing that distinguishes it from religion (and audiophilia.)

This road has already been travelled at AVS. I've asked this Q before but I'd genuinely appreciate your response as a science teacher:

Can the scientific method be used to "prove" the invalidity of the scientific method?
post #81 of 833
The scientific method depends upon the concept of falsifiability. So, while I'm sure it's not specifically answering your question Ron, conclusions previously reached can and have been proven false or must be framed in a particular context.
post #82 of 833
Thread Starter 
wow 3 pages and only 2 dacs mentioned
post #83 of 833
Chu, I agree that the method necessarily includes the concept of falsifiability. But no, you did not answer my question to HTB.
post #84 of 833
Thread Starter 
Quote:
Originally Posted by DulcetTones View Post


Wrat, I even tried to think of CD players with input so you can use their DACs, and I cannot think of a reasonably priced one that has an input and HDCD.

Cheers
DT

Thanx
Good angle I had not considered...I was hoping I could just get some quick ideas...ah well..
I will just keep an eye out for another AA DDE
post #85 of 833
Yes, TCB, I believe you did say you did some blind tests here or in the other thread. Don't seem to recall you addressing level matching or enough tests to make it statistical. Your approach, IIRC, was to make it blind and then I guess have the person do raising or lowering of volumes.
post #86 of 833
Ron, yours probably reduces to some kind of a logic question along the lines of can a false assumption prove itself wrong. I'm not sure what the answer is here. Ask someone in San Fran.
post #87 of 833
Well, I'm not so sure the scientific method holds any different weight in SF than in NYC

More curious, however, is your use of the term "assumption".
post #88 of 833
You're closer to San Fran. If you don't like assumption, replace it with approach.
post #89 of 833
Quote:
Originally Posted by Chu Gai View Post

Yes, TCB, I believe you did say you did some blind tests here or in the other thread. Don't seem to recall you addressing level matching or enough tests to make it statistical. Your approach, IIRC, was to make it blind and then I guess have the person do raising or lowering of volumes.

This is from my post on this very page:

"Of course output voltages vary, so what? I'm talking about listening to the sound of the player, not specifically about doing matched-level blind tests. When I listen to a piece of equipment, I listen to it at a variety of volumes, and listen for tonality, colorations, brightness, fullness, soundstage presentation, spatial positioning, distinction of instruments/voices, naturalness of tone, etc. I use several different pieces/types of music, and I have sometimes spent hours/days listening."

I go back and forth, if I think I hear something (say the tenor sax sounds more real on one, or the ride cymbal has a nicer ring), I'll go back to the other one, and listen for the same thing. Then I'll play with the volume, making one decidedly louder, then the other, to see if the perceived difference was merely due to loudness.

I mean, how freakin hard is that? It's pretty logical, and it's no different that comparing TVs - you put in different movies, look at a cable feed, adjust one, adjust the other... it's not rocket science!
post #90 of 833
Well, with all due respect, that approach confounds matters, involves advanced knowledge of the components, and has no statistical signficance. On matters such as we've discussed here (DAC's, wires, CDP's) the approach readily allows for unintentional changes in auditory focus leading to unpredictable results. I might also add Ethan's comments regarding comb filtering effects too. Comparing TV's to me would involve calibration with a trained technician.
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