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PostPosted: Sun Feb 22, 2009 12:23 pm 
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Captain Spaulding wrote:
MikeC, IIRC you have some experience with high-end turntables. Care to weigh in?

Yes I do... but no I don't care to weigh in. Way too many words spent in similar discussions in the past. I admit the convenience and ready availability of new music on digital far outweighs any superiority of vinyl for me these days. My Linn LP12 / Ekos has sat idle, unplugged from AC, for many months.

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PostPosted: Sun Feb 22, 2009 2:32 pm 
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Captain Spaulding wrote:
Quote:
In fact, I would argue that one of the reasons vinyl remains so popular is because it blurs the audio in a way that hides flaws in the mix and mastering process.


This has simply not been my experience with any turntable Rega-entry-level or better. Aside from surface noise, the main difference I have observed between good vinyl and good digital is that vinyl conveys the timbres and textures of instruments more realistically. It doesn't blur anything, which can be unfortunate in the case of bad recordings.


There is another reason. CDs tend to be much, much louder than vinyl. Vinyl simply cannot reproduce the extreme loudness that CDs can, because the grooves would become too big and the stylus would not be able to properly follow them. Also, as vinyl recordings are usually much older than the CD version chances are they were produced before the start of the loudness war.

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PostPosted: Fri Feb 27, 2009 3:49 am 
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Devonavar wrote:
MoJo wrote:
That's the ridiculous. Subjectivity has nothing to do with it, either a certain human being can perceive a difference or they cannot


Subjective means specific to one particular subject (i.e. one listener), as opposed to something which is true for all subjects. Whether there is a definite fact about what the subject perceives is irrelevant — it's the "certain human being" part that makes it subjective, not that subject's certainty about the content of his own experience (that should never be in question). That said, you address this in your next point...

MoJo wrote:
That's why ABX tests are always done by more than one person. It's a basic scientific principal - results from any experiment must be repeatable.

If five people with undamaged hearing and good knowledge of how to listen to high-end audio can't differentiate two sources in an ABX test, you can be 99.9% sure that no-one can.


I will quibble and say that a sample size of five isn't enough to draw the margin of error you desire, but I think we basically agree. I see no reason why the ABX process necessarily requires multiple samples, which is why I have been arguing against it, but, yes, in principle ABXing could be used to draw (somewhat) objective conclusions if it was used as part of a large scale study. But, note that the objectivity comes from the sample size, not the ABX test in itself. You could obtain similar results without ABXing if a certain percentage of your test subjects were able to identify a similar difference between two sources (you would need to take steps to avoid samples "contaminating" each other with the power of suggestion).

MoJo wrote:
I was suggesting that it would be worth doing an ABX test to determine if there is any difference between pure bit-perfect TrueHD and down-sampled TrueHD from a Radeon 4800. To be honest that is probably beyond the scope of an SPCR review... It's more like something AV Forums should do, but probably won't.


Yes, well beyond, since this is essentially a test of whether people can hear the difference between 48 and 96 kHz audio. SPCR definitely doesn't have the resources to run a large scale survey like this. I don't see how AVS forum could either, since there's no practical way to standardize a playback system (and space) over the internet.

That said, I think the point is already proven. I've seen / read about enough recording engineers who can point out differences between the two to believe that there is an audible difference, at least in a studio setting. (In other words, I have seen a big enough sample size to draw at least a minimally objective conclusion.) However, I wouldn't generalize this outside of the studio — studio quality playback systems (including room acoustics) are simply too rare in the rest of the world. I believe that most people could be trained to distinguish 48 vs. 96 kHz audio in a studio, but I know that outside of these tightly controlled conditions, the difference disappears quickly.


You're incorrect about the 96 khz claim. It's far from conclusive that people can actually regularly hear the difference at normal listening levels. For example the JAES study http://www.aes.org/e-lib/browse.cfm?elib=14195 was rather controversial but it showed most people can't tell the difference between CD quality, and higher word length and sampling rate audio and this included audio engineers. There's also some related information on Hydrogen audio http://www.hydrogenaudio.org/forums/ind ... opic=40134. Now it may be true that people can be trained or you can come up with specific samples in specific conditions but that's generally not of great interest for the real world.

As for your claim "you could obtain similar results without ABXing if a certain percentage of your test subjects were able to identify a similar difference between two sources (you would need to take steps to avoid samples "contaminating" each other with the power of suggestion)." either I don't understand what your are saying or you don't understand what ABX is. ABX is basically a double blind test.

The reason why double blind is so important in the scientific context is because we are only interested in differences that actually exist (this isn't a very good description but it's good enough for the context). In a medical context, we want to know if a drug is actually better then no drug or a previous drug. We don't want to be confused because people think the drug is making them better (or worse) aka the placebo effect or their doctors think likewise.

The same in the audio context. The fact that people think a 96khz sample should be better then a 48khz sample and there consistently say it's different is of no interest to us. (Or the fact the person administrating the test does and therefore promotes the 96 khz sample more heavily).

Or if we're comparing two brands of products, the fact that the product branded HIGH QUALITY MADE IN USE is consistently said to be different then LOW QUALITY MADE IN CHINA by people when they know the brands is of no interest to us.

If you think asking people to identify the difference is going to be enough you're mistaken. It's quite easily possible that people will come up with the same nonsense about why something sounds different particularly since audio is an area most people probably lack any real ability to describe differences other then with mostly meaningless phrases even more so since it's easily possible the person administering the test will end up helping the person describe the differences when they are trying to work out what the person is actually trying to say.

Ultimately of course, the key thing is it makes little sense to go through all these risks and potential confounding factors, when an ABX test is simple and based on a basic scientific principle and can be analysed statisticly in a relatively straighforward and well understood manner.

What we want to know is, can people actually hear a difference? The fact that they just claim there's a difference when they believe there should or the people administering the test (inadvertently perhaps) lead them to believe there should be is of no interest to us.

Of course you're right that fact that people can hear a difference doesn't mean one is better.

P.S. Of course you don't actually need a double blind test. You could do an AB test for example. But ABX generally allows you to get results with a similar confidence interval with a smaller sample size


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PostPosted: Tue Mar 03, 2009 11:33 am 
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Nil Einne wrote:
You're incorrect about the 96 khz claim.


I should have been more specific. I generally agree with all your comments (thanks for linking to that AES study btw). What I've seen has suggested that *some* engineers can hear differences under *some* circumstances. In a mastering situation, I think that matters because of the way processing errors build up. The earlier in the mix you can catch the errors, the smaller they will be down the processing chain. For strictly listening purposes though, I'd agree with you that there's no generally audible difference between 48 and 96 kHz.

Nil Einne wrote:
As for your claim "you could obtain similar results without ABXing if a certain percentage of your test subjects were able to identify a similar difference between two sources (you would need to take steps to avoid samples "contaminating" each other with the power of suggestion)." either I don't understand what your are saying or you don't understand what ABX is. ABX is basically a double blind test.

<snip>

P.S. Of course you don't actually need a double blind test. You could do an AB test for example. But ABX generally allows you to get results with a similar confidence interval with a smaller sample size


It's the former. You've restated more or less what I meant in your postscript. I would only add that, rather than simply listening for a difference (which is of very limited use when trying to make a value judgement), it is better to get listeners to describe the differences they claim to hear. Descriptions that are common to a statistically significant portion of the sample can then be qualified and descriptions that do not find corroboration can then be discarded as "placebo" differences. Obviously, priming though the power of suggestion would need to be controlled for.


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PostPosted: Mon Mar 15, 2010 8:04 am 
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best card/s + sware for S/PDIF or HDMI-Audio input & decode of DD/DTS (inc HD) formats

I'm just curious as to what people believe to be the best card nowadays for digital-in of the various surround formats created by DD & DTS.
[they're responsible for 99% of SS encoded content right?]

Initially it'd only be for taking encoded content from my Xbox360 & Wi...
But soon it'd also be for a PS3 which for BD content I believe uses newer DD & DTS formats, namely: TrueHD, & HD MA.

Ideally it'd be happy to take any DTS/DD content thrown at it, & pass it to the appropriate (licensed) software for decoding.
[or hardware if there's a card that can do this]

Mostly I'd like to decode and run it through a stereo surround simulation scheme like; DH, CMSS, or DTS-SS.
But occasionally I'll decode/convert & do multi-channel analogue-out via my Essence ST + H6 (7.1 daughter-board).

I was investigating X-Fi cards but they seem to have regressed in this area recently, I hope it's not a conscious trend influenced by big content!
I'm yet to check out Auzentech and Xonar cards for this use....

Then I got to thinking, maybe HDMI-audio capable devices are better suited for this sort of thing than S/PDIF?
Perhaps there's sound-cards that can take HDMI-in, or if not graphics cards?

I know that currently "bit-stream in" for graphics cards acts only as a pass-through to AVR's etc.
The big question mark is if there's dvrs/software that can recognise this incoming bit-stream, & instead decompress it.
Then we have raw digital PCM ready for decoding...

I'm guessing this step is something deliberately kept in the realm of AVR's, but if there's a way, perhaps it's a better path than via S/PDIF?

Assuming a way is found...
Then it's a matter of redirecting the PCM stream to software or hardware (assuming there's cards) decoder/s.
And then (in my situation) have this decoded signal pass through the analogue output circuitry of an Essence ST + H6.

Utopia/profit! :D


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PostPosted: Tue Mar 16, 2010 12:51 am 
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Prolly the best solutions I've come across so far are: HDAV1.3 or Hometheatre HD

Quote: A main feature of the HTHD 7.1 is offering HDMI 1.3a I/O to the end user which allows full resolution, high definition audio with no down sampling. A very interesting feature of the HTHD 7.1 is the use of an external receiver is NOT required to have support for these high definition standards.
While the use of an external receiver is an option, the card allows any speaker system connected to the card to output Dolby Digital Plus, Dolby True HD and DTS-HDMA in full resolution.


What's not certain to me yet is whether these cards can decode & do dac to DTS/DD content (HD or non-HD) coming via HDMI, instead of locally.

Even more ideal would be to use my existing Core i3-530 + motherboard w/HDMI-in...
But I'm not sure if Intel HD Graphics is able to receive A/V via HDMI, let alone decode w/approp. s'ware & redirect to 3rd party DAC.
I doubt it's able to, nor do I expect it'd be possible with sw updates & right mobo/adapters, but TBH I'm not 100% certain!

The main reasons I want something like this is to;
1) Send digi-Audio (HD or non-HD) to my PC to create virtual surround in stereo (CMSS, DH etc)...
2) Have a PAP* compliant solution so I can receive & play or locally play HD A/V, for the times I'm too lazy to rip/transcode.

It's a shame that I prolly won't be able to redirect decoded DD & DTS formats to my Essence ST + H6 for superior analogue output.
I suspect that'd break the PAP/xxx....
So for analogue-out of received or locally played HD DD & DTS, I'll be forced to use the same card.
Unless I've gone to the effort of ripping & transcoding beforehand...

*forgotten what the video equivalent is called


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PostPosted: Tue Mar 16, 2010 9:37 am 
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anyone? thank-you.


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PostPosted: Tue Mar 16, 2010 10:20 pm 
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guess not....
thanks anyway I guess.


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PostPosted: Sun Mar 21, 2010 12:37 am 
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Location: Australia
Anyone know if this card can do dd/dts 5.1 decode on s/pdif-in?
I've checked an it doesn't seem like it but just checking.
What about Hometheater HD?

Thank-you.


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