Master Clock Talk

[morphsci]

Quote:

Originally Posted by lowmagnet /img/forum/go_quote.gif Ah, so you're talking about re-clock the internal CD player DAC and using its line-out or headphone out, right?

Right on the Money

 

[Filburt]

Looking at the way these things are installed, I'm left wondering if much of the perceived change in sound is, if not placebotic (which seems like a real possibility), caused by various noise injected by these devices into the system, or if some of the installations are actually producing very high levels of jitter. Has anyone done any measurements to analyse the effects of these devices and the manner in which they're commonly installed?

 

[lowmagnet]

Quote:

Originally Posted by Filburt /img/forum/go_quote.gif Looking at the way these things are installed, I'm left wondering if much of the perceived change in sound is, if not placebotic (which seems like a real possibility), caused by various noise injected by these devices into the system, or if some of the installations are actually producing very high levels of jitter. Has anyone done any measurements to analyse the effects of these devices and the manner in which they're commonly installed?

Well, all of the 'magic' behind the patents held by Amar Bose's company are based around adding noise/reflections to create ambiance. They tested it blind in Canada's labs and found people prefer it and think it's detail, even though the opposite is true.

Grain on a photo is obvious if you look up close, but far enough back it looks like natural texture from the scene photographed.

 

[PhilS]

Quote:

Originally Posted by meat01 /img/forum/go_quote.gif Hi Phil, do you have another method that determines if a $300 upgrade is really worth it or not? I understand where hciman77 is coming from. Right now, a blind test seems to be the best way to take placebo out of the equation, since it is a strong factor. My argument has always been that if the change is worth it, then it should be apparent even with a blind test. The problem is that blind tests are not always an option.

Yes, I believe the best way for me to determine it is to listen to the upgrade in my system for an extensive period of time over several days using my usual equipment and listening to music that I am intimately, intamately familiar with, recognizing all the while that the $300 upgrade may in fact make things sound no better or maybe even worse, that I could readily use the $300 elsewhere, and that my initial impressions may be false and should be confirmed with additional listening.

In short, I don't think a blind test, which would be a pain in the butt to do utilizing the parameters I think are important, is necessary to make the judgment. Could it be helpful? Possibly, i.e, it would be probative of a difference. Could it be what others need such a test to have confidence in their judgments? Perhaps. But many of us are confident in our own faculties, including our hearing ability, our experience with various types of upgrades, and our ability not to be duped by "placebo" into wasting money.

 

[lini]

Quote:

Originally Posted by Filburt /img/forum/go_quote.gif Looking at the way these things are installed, I'm left wondering if much of the perceived change in sound is, if not placebotic (which seems like a real possibility), caused by various noise injected by these devices into the system, or if some of the installations are actually producing very high levels of jitter. Has anyone done any measurements to analyse the effects of these devices and the manner in which they're commonly installed?

Good question - and I'd love to see back-up measurements on that, too. Problem is that jitter measurement systems are all pretty expensive, so most modders just have to go by ear only.

Greetings from Munich!

Manfred / lini

 

[hciman77]

Quote:

Originally Posted by lini /img/forum/go_quote.gif Good question - and I'd love to see back-up measurements on that, too. Problem is that jitter measurement systems are all pretty expensive, so most modders just have to go by ear only.

So they cannot prove that they are in fact lowering jitter ?. In a TNT article I read a chap accidentally added 500ps of jitter to the already jittery Marantz CD67(iirc), he thought it sounded better, he was not aware at the time that he had added jitter but he was aware that he had changed the circuit so it is a sighted test.

Similarly in a white paper

http://akmedia.digidesign.com/suppor...tter_30957.pdf

I read that was touting a new (very low jitter) clock mechanism the subjective listeners tests showed that listeners preferred the sound from older more jittery clocks, I cannot remember if these were sighted or bind tests, I think they must have been sighted. Suffice to say the Authors of the paper were somewhat puzzled by this result.

 

[budx3385]

Hmm. It appears that some folks are dubious. I will grant you that there are many people who can't even hear the difference that lossy codex makes and are i-happy.

However, I will gladly invite any serious hf'er to hear the difference the net-audio mods made in my Rotel 965BX, which I described in the DIY forum. I had been using a particularly pristine D-303 and a DCP-100 as source for my PPX3 Slam, and I repeatedly made ABx comparisons before and after the upgrade steps in the Rotel. I guarantee you that it would not have displaced the pcdps as source if it had not surpassed them in SQ for my picayune ears. I readily admit that I really need to spend time listening to music for emotional refreshment, and I just don't have time to waste with inadequate SQ.

IMHO, of course. Happy listening to all.

 

[Filburt]

Well, there are two inquiries really occurring here. One is whether the mods produce audible results, the second is why. The modifications may be producing audible results, but it isn't necessarily due to a reduction of jitter (in fact, perhaps the opposite is occurring or there is noise being produced, or something of that sort).

 

[Pars]

Quote:

Originally Posted by filburt in fact, perhaps the opposite is occurring or there is noise being produced, or something of that sort

Then again, perhaps not. I just know the Tent XO/Flea/Tread PSU combo isn't coming out of my Rotel, and I could easily put it back to stock. It is troublesome to me to do an upgrade that I can't measure the effects of, however.

I don't bite on cables, etc. Yeah, they may make a difference (and I have heard some), but they shouldn't from an electrical perspective. Expensive tone controls is what I basically think they are... sure are alot for sale here, on Audiogon, etc. I don't seem to recall seeing many clock boards for sale used though... And from a technical perspective they do have merit

 

[Filburt]

Quote:

Originally Posted by Pars /img/forum/go_quote.gif Then again, perhaps not. I just know the Tent XO/Flea/Tread PSU combo isn't coming out of my Rotel, and I could easily put it back to stock. It is troublesome to me to do an upgrade that I can't measure the effects of, however. I don't bite on cables, etc. Yeah, they may make a difference (and I have heard some), but they shouldn't from an electrical perspective. Expensive tone controls is what I basically think they are... sure are alot for sale here, on Audiogon, etc. I don't seem to recall seeing many clock boards for sale used though... And from a technical perspective they do have merit

Hmm...I've seen several comments here that seem to exxagerate about how something isn't measureable or ought not to show any difference in a scientifically controlled test. I don't think I've ever encountered a verifiable change in qualia in my experience with audio that wasn't measureable in some fashion; it just sometimes comes to measuring something less conventional than THD+N or something of that sort. I don't generally find cables to make a particularly audible difference, but the main reason I don't really bother with them in general is I don't think the price/performance ratio is tolerable relative many other things I could be doing with my money, even in audio.

It's plausible to me that some of these modifications are producing audible results, but I'm not confident that it's due to jitter reduction.

 

[Pars]

Quote:

Originally Posted by Filburt /img/forum/go_quote.gif Hmm...I've seen several comments here that seem to exxagerate about how something isn't measureable or ought not to show any difference in a scientifically controlled test. I don't think I've ever encountered a verifiable change in qualia in my experience with audio that wasn't measureable in some fashion; it just sometimes comes to measuring something less conventional than THD+N or something of that sort. I don't generally find cables to make a particularly audible difference, but the main reason I don't really bother with them in general is I don't think the price/performance ratio is tolerable relative many other things I could be doing with my money, even in audio. It's plausible to me that some of these modifications are producing audible results, but I'm not confident that it's due to jitter reduction.

It is measurable if you have the equipment to do so... most don't as it is rather expensive. I'm not even sure exactly what you need to measure jitter... the plots I have seen appear to be from a spectrum analyzer. I would agree with the second half of your first paragraph. And from what I am hearing, I am confident that the jitter is reduced significantly.

I'm not participating in the thread to try to convince anyone to do a clock upgrade, though I will say that it is one of the most worthwhile ones that I have done, far outstripping any changes I have made so far to the output stage (opamps from NE5532 stock to AD826/LM6172 and currently AD4562; output caps changed from stock BG F to BG NX). And I certainly would not open a thread up with this title

 

[colonelkernel8]

Thanks. Whatever. I guess its just my imagination that everyone who listens to my upgraded CD player, not having any knowledge of it being upgraded, ask me why it sounds so much better.

Mysterious, isn't it?

Renamed the thread to better reflect the discussion.

 

[udo]

I like the real world scenario's:

I have a NAD C521 CD player going into a Zhaolu D2.5C with Zapfilter.
For those of you knowing the NAD: would it be worth (audible...) enough to upgrade the clock in the player?

I also have a M-Audio DIO2496 soundcard which feeds the same DAC, could/should I upgrade the clock on the card as well?

Would I need an 'expensive' clock or could a better specced 1pps clock (like I have in my Zhaolu 1.3, hanging from rubber bands) be enough?

 

[hciman77]

Quote:

Originally Posted by colonelkernel8 /img/forum/go_quote.gif Thanks. Whatever. I guess its just my imagination that everyone who listens to my upgraded CD player, not having any knowledge of it being upgraded, ask me why it sounds so much better. Mysterious, isn't it? Renamed the thread to better reflect the discussion.

Apart from being wholly anecdotal, wholly uncontrolled for instance your listeners heard the same CDs when they listened before and after the Mods ? and the levels were carefully calibrated to stay the same and tested as output voltage not pot setting ? and relying on possibly weeks old audio memory , there are just too many variables involved. Just 0.1db level change is audible for instance - even taking that into account none of it indicates that any changes can be attributed to jitter since you cannot provide jitter figures before and after...

.

 

[morphsci]

Quote:

Originally Posted by hciman77 /img/forum/go_quote.gif Apart from being wholly anecdotal, wholly uncontrolled for instance your listeners heard the same CDs when they listened before and after the Mods ? and the levels were carefully calibrated to stay the same and tested as output voltage not pot setting ? and relying on possibly weeks old audio memory , there are just too many variables involved. Just 0.1db level change is audible for instance - even taking that into account none of it indicates that any changes can be attributed to jitter since you cannot provide jitter figures before and after... .

You need to chill out. You are starting to appear as if you have some agenda. It's about the music. I listen to music to enjoy it. I buy components to further that end. I do not have to prove to myself that something measures better. If it sounds better, it is better, to me.

And before you get on your high-horse and start spouting some pseudoscientific nonsense about subjective vs. objective, realize that I don't care. I teach statistics at the undergraduate and graduate level and am well aware about the efficacy of DBT's as a methodology. In audio, every (YES EVERY) DBT I have seen is severely compromised by statistical desgn flaws ranging from inadequate sample sizes (and hence power) to blatently confounded variables. A DBT is only as good as the statistical design it is used under and furthermore is not by definition more objective than a sighted listening test. In fact it is not even necessarily less biased, since that is a function of the design and specific measurements that are made.

Wooo ... that feels better.