RF Attenuators = Jitter Reducers

[SY]

What I'm saying is that your tests on the attenuators are invalid. This was pointed out to you on a number of occasions & you refused to test their purported operation. What was the purpose of your test? Nobody ever denied that fixing up the termination of the input stage would be a better solution but not too many people have the desire to open up their DACs & the equipment to measure the impedance of their cable/DAC input stage.

5.

 

[jkeny]

George, just to clarify, in case there is any misunderstanding - Sy was aware of the commercial nature of the modified Hiface before he started this. I don't sell or have any commercial interest in attenuators!

 

[aardvarkash10]

yawnies.

Agreement to disagree yet?

 

[ThorstenL]

Dear Sy,

Well then, you're postulating that the jitter frequency is less than the linewidth, on the order of a couple of hertz.

Not to be obnoxious, but please compare your measurements to known baselines.

The line-width in your measurements is considerable and not easily explained away, unless you decide not to.

In fact, I would considerably suggest that I may take serious umbrage should you ever be foolish enough to attempt publication of your results so far in any serious context.

Looking at your posted results you seem 20dB short of 16 Bit equivalent resolution.

Why any competent and educated engineer who knows his or her beans would bother posting ** like that escapes me, but it's your funeral.

To be honest, on this one I expected to have a fight, instead I have a cringing default. Please upgrade your basic (EE101,EE102,EE201) skills and learn how to use and interpret FFT's before you bother any of us again. To be honest, I am severely appalled. Do they hand degrees in the US with McDonald Happy meals?

Oh. And next time you use your "impeccable" measurement setup, can I PLEASE have a noisefloor at the technical limits of 20 bits (see JK2's measurements of the sabre DAC earlier in this thread as example), instead of one that is broadly equivalent (for 64K bins) to 13 bit resolution.

A few decades ago my professor in "Measurement Techniques" used to have a mantra - "Wer misst misst mist" ( it's german, missing the pith and punch, it roughly translates to : "He who measures measures manure.")

Ciao T

 

[SY]

Another Augean Stables post. Ho hum.

http://www.diyaudio.com/forums/digi...tenuators-jitter-reducers-18.html#post2354763

 

[ThorstenL]

Sy,

Another Augean Stables post. Ho hum.

Forgive me, but do you really make any claim that with an FFT noisefloor at -125dB your measurements amount to a heap of beans at the very least?

Do you really want me to post a photomontage of the stereophile measurements I referenced to actually have the same scale as your measurents posted?

I mean forgive me, but you offered me to pay you for consultancy (in another thread) in case I could not hack it myself.

Do you even understand the implications of what you post?

I would appreciate an honest and lucid answer, mind you, not that I expect one...

Ciao T

 

[aardvarkash10]

dance little angels - dance!

 

[SY]

I would appreciate an honest and lucid answer, mind you, not that I expect one...

Lacking an honest and lucid question, I cannot.

 

[ThorstenL]

Hi Sy,

Lacking an honest and lucid question, I cannot.

Okay, again:

"do you really make any claim that with an FFT noisefloor at -125dB your measurements amount to a heap of beans at the very least?"

"Do you even understand the implications of what you post?"

Answers on a postcard or in a pinch in this tread will do.

Ciao T

 

[SY]

Still haven't gotten an honest question.

 

[ThorstenL]

Dear Sy,

Still haven't gotten an honest question.

Here is a very honest one and one I'd like your own take for, in public, on the record:

Sy..

"do you really make any claim that with an FFT noisefloor at -125dB your measurements amount to a heap of beans at the very least?"

Or in other words, with a noisefloor in your measurements around 20dB higher (in other words ten times) of what an ideal 16 Bit digital audio system should deliver, do you propose anyone should take your conclusion "I cannot measure a difference" as relevant, given ze zevere lack of resolution in your methode?

Would you care to answer to these issues?

Ciao T

 

[SY]

Start with a false premise, don't bother reading any of the posts to understand the test setup, make up some nonexistent issues, then demand an answer. Sorry, I don't volunteer for stable duty. Find your fun elsewhere. Save keystrokes. I will.

 

[wakibaki]

Again, I ask you to show a measurement of a published low jitter device using your set-up to prove it can resolve what your are claiming - talking about noise floor, etc. is not proving the capability of the set-up!

Why not buy an Emu 1616M, modify it according to ThorstenL's suggestion and do the test yourself? It'd be what we call colloquially in the UK a piece of p*ss.

You can get a copy of Visual Analyser here: Visual Analyser details

It outputs test tones too.

I don't know why I'm helping you like this, just a kind-hearted old fool I guess.

w

 

[wakibaki]

I see Joseph K has totally failed to respond to my suggestion that he should perform the test himself, or provide any explanation as to why he can't.

w

 

[wakibaki]

ThorstenL is full of criticism of SY's test procedure, but conveniently can't undertake testing himself.

w

 

[wakibaki]

It's getting to the point where even if you do post results of your own, your prevarications will have undermined your credibility to the point where you won't be believed even if you DO post positive results.

w

 

[wakibaki]

Joseph K, you first posted your screenshots in June. They were supposed to show the general applicability of attenuators for jitter reduction. Eventually you retracted this claim, stating that the results apply only to the HiFace.

Joseph K has a $30,000 oscilloscope Shame about his credibility.

Come on you guys, we're all waiting. 695 posts and we're still waiting. We could be wrong about the attenuators, but put yourselves in our shoes, you'd be pretty fed up waiting by now yourselves.

You owe us an apology on this score alone.

w

 

[woodturner-fran]

are we there yet
are we there yet
are we there yet
are we there yet
are we there yet
are we there yet
are we there yet
are we there yet


A chance at summary of the almost 700 posts on this thread. Just in case....

1. jkeny tries these attenuators and hears an improvement.
2. He brings it to the attention of some people, tells them where to buy the things if they're interested.
3. He gets hammered for making the suggestion....never mind that people are free to make up their own minds..... purchase is not compulsory.
4. Almost all the people knocking the devices have not used them. Curiously, those who have rather like what they do.
5. The device costs $14!
6. In the interests of settling (or winning) an argument, jkeny offers to send one to an errm, impartial party.
7. Said party conducts tests which there is much dispute over (oh my sweet jesus is there much dispute) and concludes there is nothing different.
8. 2 other sets of measurements exist which do show a difference.

So what have we learned? huh?

Someone who heard an improvement with $14 devices got hammered for even making the suggestion. Those who are doing the hammering have not and will not listen to said device.


Jesus, give me a break.



Fran

 

[SY]

Fran: To be clear, my agreement was to test John's $500 box. The attenuators were also packed in there so were included at his request. I had no idea they were coming and was unaware of his claims regarding them.

 

[woodturner-fran]

oh, BTW, I hear there's jobs going in the Vatican. Get you applications in quick, you're (plural) a shoe-in for the job.


EDIT: but that evolved really quickly into something else SY.