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Old 3rd November 2010, 10:11 AM   #291
jkeny is offline jkeny  Ireland
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I believe this post on the enable thread is an interesting & cogent read EnABL - Technical discussion
 
Old 3rd November 2010, 03:32 PM   #292
Previously: Kuei Yang Wang
 
Join Date: Nov 2002
Hi Sy,

Quote:
Originally Posted by SY View Post
Well, especially because I never said *I* was going to measure jitter. That's made up as well. I'm strictly looking at analog outputs.
So, what are you going to measure then?

I mean measurements should be meaningful to illustrate and quantify the subject.

I mean I can take a scope and look at the output from two different CD-Players and pronounce "they look the same". Of course, I would have perfectly wasted my time.

L8er T
 
Old 3rd November 2010, 03:43 PM   #293
Previously: Kuei Yang Wang
 
Join Date: Nov 2002
Sy!

Quote:
Originally Posted by SY View Post
DACs are M-Audio 192 and DCX2496, both of which measure impeccably in the analog domain.
DON'T EVER do that again. Please? You made me laugh so hard, I probably nearly got a heart attack and several co-workes gave me strange glances to see if I was finally loosing my marbles and was going postal.

I have not laughed so much since seeing the advertisement fort the "teleportation tweak", but this is better!

Ciao T
 
Old 3rd November 2010, 03:55 PM   #294
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Quote:
I mean I can take a scope and look at the output from two different CD-Players and pronounce "they look the same". Of course, I would have perfectly wasted my time.
Nice! I have done just that, on a recent unit of a stock Hiface, and the result is:
Attached Images
File Type: png Plot.png (97.9 KB, 140 views)
 
Old 3rd November 2010, 03:59 PM   #295
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Of which the most educating is the TIE trend trace and the phase noise plot, here zoomed in:
It's educating, for me, because the TIE trend trace is almost an exact copy of the Hiface clock power supply scope trace posted earlier by Jkeny.. The same 80 khz modulation pops up also here, plus some more low freq periodicity.
Attached Images
File Type: png Plot(1).png (101.1 KB, 142 views)
File Type: png Plot(3).png (51.3 KB, 139 views)

Last edited by Joseph K; 3rd November 2010 at 04:08 PM.
 
Old 3rd November 2010, 04:03 PM   #296
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Then I had put the scope on a second, older stock Hiface unit, just to see if there is a difference:
Attached Images
File Type: png Plot.png (95.6 KB, 141 views)
File Type: png Plot(1).png (95.2 KB, 135 views)
File Type: png Plot(3).png (59.2 KB, 35 views)

Last edited by Joseph K; 3rd November 2010 at 04:13 PM.
 
Old 3rd November 2010, 04:07 PM   #297
Previously: Kuei Yang Wang
 
Join Date: Nov 2002
Hi,

Quote:
Originally Posted by wakibaki View Post
I think it highly unlikely that SY will discover any measurable or audible difference as a result of jkeny's modifications.
Completely agreed. Though in my case simply because I cannot muster the slightest shred of respect of what Sy proposes as "Measurement Equipment" and his listening tests will carry so much expectation bias, much more gross differences will produce a Null.

Again, what I do need to ask, why make meaningless test, without adequate test gear, make blind listening tests without sufficient calibration etc.

Sure, it is all good fun, but I for sure would not be keen to write about it, as I would be aware of the futility of it and convinced some Subjectivist/Objectivist like me (short SOB) would come along and berate me (quite rightly too) for it.

Quote:
Originally Posted by wakibaki View Post
I think it highly unlikely that there will be any measurable difference.
With this "Measurement Gear". Yup. I mean Sy is really good at making funny jokes.

An AP2 is not good enough for serious jitter measurements, though it would likely show up what what J-Kenny does.

Quote:
Originally Posted by wakibaki View Post
I think it highly unlikely that should there prove to be any measurable difference that it will be audible.
Good, then why don't you go and buy the best and most technologically advanced hifi gear on the planet? I am sure B*se will point out their stuff measures well if you use that sort of test gear.

Quote:
Originally Posted by wakibaki View Post
ThorstenL, your attitude toward SY is mean-spirited and uncalled-for.
He is hamming up big time, so why should not I?

Quote:
Originally Posted by wakibaki View Post
'I hope your kit is good enough to measure jitter.'

It's perfectly obvious to the rest of us that what you hope and believe and the meaning which you intend to convey is the exact opposite.
In the case of Sy I have long given up any hope. As for beliefs, I have no use for faith, belief and such modes of the human mind, I shall leave them to such as you and Sy. I never believe anything.

Quote:
Originally Posted by wakibaki View Post
Try and conjure up some crumb of true generosity.
You mean given that Sy's teat gear is woefully inadequate I should offer to do the tests instead?

I'd love to old man, but I can't, contractual obligations.

Ciao T
 
Old 3rd November 2010, 04:17 PM   #298
Previously: Kuei Yang Wang
 
Join Date: Nov 2002
Hi,

Quote:
Originally Posted by Joseph K View Post
Nice! I have done just that, on a recent unit of a stock Hiface, and the result is:
Nice plots! What 'scope you got? Looks like I need one.

BTW, Sy and myself where refering to looking at the analogue output from a DAC following the HiFace. In Sy's case the DAC being a Behringer DCX2496 DSP based crossover with a nice Cirrus Logic ASRC on the input to propperly louse things up for good measure.

Ciao T
 
Old 3rd November 2010, 04:38 PM   #299
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A TEK 7354. 35 000 Euro, in case You wanted to ask... Stock, without the jitter analysis package. That can cost another 10000 in a worst case..

Short of the story: recently we had been looking for candidates for a possible investment, at my job, not me, naturally!
So I had tested some middle-heavy weight modern beasts - was a joyride.. The most beautiful one was a LEcroy WavePro 760.
6 Ghz/ 40Gsps. Though today it is "low end", their top one is 45GHz/ 120Gsps..
We had concluded that Lecroy is having really interesting offers, - very strange, normally I would have never thought of voting against a Tek scope..

The sad side of the story is that the fun had finished there - now will have to wait until the order arrives. That is, no more tests for the moment.

Last edited by Joseph K; 3rd November 2010 at 04:56 PM.
 
Old 3rd November 2010, 04:50 PM   #300
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Thorsten - yes, I had followed the thread, and know what are You talking about.
Also what Sy is talking about. That is why I wanted to post these few shots, to show that "at the source", at the input of his DAC providing his results, there are real differences in the incoming SPDIF data.
And this thread is about characterization of the SPDIF transmitter unit, that is, the resulting SPDIF stream, not the DAC output.
One can just not guess what will be connected to this stream.

If somebody is interested, I'm more than willing to explain more about these graphs. It's fun to see easily all the up to now "suspected" effects - being just that, effects existing really..
 

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