Everything sounds the same

[marce]

17 minutes ago, sandyk said:

Hi Peter

 It's just after 5AM here , and I have to leave for Sydney at 6AM. I will be in Sydney all day.
These were from a series of pairs of TV screen  photos that Dennis has seen, that illustrate ,. but don't by themselves prove the differences between the comparison Music Videos on BR discs with identical check sums that I sent him, even with a cheat sheet pointing out the most obvious differences. That's what the actual BR discs are for ! 
They were taken from my Samsung 40" HD TV using a cheap Canon A480 camera without access to a  tripod, and needed a little straightening (2degrees anti clockwise.) and cropping  in Photoshop.

 
 Both versions of the Music Videos were saved to the same folder on a USB memory stick.
 I took these as a last resort to try and show Dennis what his Laptop and projector were not capable of resolving, with the very obvious audible differences either from the BR discs with .mp4 videos on them, or as a last resort the USB memory stick I also sent him. (His BR player wouldn't play .mp4 videos)

Audiophile Neuroscience and 2 of his friends have also verified my reports via David's new 4K TV.

 I deliberately put the comparison videos on BR discs to be played from a decent media player such as an Oppo 103 or later model via HDMI into a HDTV to get away from crappy laptops and mediocre PCs.

Basically, the duller and less contrast versions were created by plugging a USB memory stick into a >3M long USB cable plugged into a USB 3.0 front port.

 The more detailed and higher contrast versions were created using a USB Regen powered via a JLH PSU add-on where one of the parallel 4700uF electros in the capacitance multiplier section was replaced by a Low ESR Panasonic FC 4700uF which accentuated HF detail with both A and V.

The last series of 6 pairs of comparison video images were mainly obtained by pausing the Oppo 103 on the several seconds long artist photo at the start of the SNL clips, were taken in strict order to show that I hadn't just tried to manipulate the results.

 In each case the duller looking version has the lower img.xxx number.

Both versions were from the same source file on my OS SSD.

 

The only thing that Identical Checksums gives is the possibility of REGENERATING an A or V file to CLOSE to that of the original. How an Audio file will sound , or a Video look, is governed mainly by the PSU area and how electrically quiet the computer is.

 

Did you modify the computer in the display device that displays the image.

[marce]

1 minute ago, PeterSt said:

 

So in advance you're telling that you can't do it. I know, this is not exactly what you say, but what to think else.

Thus, easy said eh ?

 

Bummer. We're stuck.

 

Read a lot of my posts on other threads where I have given quite a bit of advice regarding noise etc.

You really do have to find the lowest denominator.

[marce]

1 minute ago, PeterSt said:

 

That's exactly our problem. Or your problem. No wait, you don't have a problem with it at all.

Easy said though.

 

7500 euros. Take it up.

I have a problem with it every day, as do many others... On Ralphs thread regarding DAC's I gave quite a long reply on some problems with DAC's mainly regarding layout, a critical factor in any circuit working at it's best.

[marce]

5 minutes ago, PeterSt said:

 

All right. Which Ralph and which thread (no, post), please ?

I will not focus on being your pain in there, but I might coincidentally be.

Thank you, Marce.

 

there are many other posts here and on other forums regarding noise and noise mitigation etc.

[marce]

8 hours ago, fas42 said:

 

All systems colour ... normally. What we're aiming for is zero audible colouring by any part of the rig - and the cable by impacting the analogue qualities of the digital transmission of data plays a part in that; 

Please explain how the cable carrying a digital signal can have an effect on the analogue qualities, when the analogue signal is burried in the data and you would have to change specific bits to change the analogue.... Or are you going on about the effect the cable has on the digital waveform, again if the data gets through (and it does)then the cable has done its job...

[marce]

8 hours ago, fas42 said:

 

The 'thinking' that makes it very straighforward to digest is to consider that every system is an electrical gestalt - sticking big labels on one set of boxes with the word DIGITAL, and the other set with the word ANALOGUE is a nice convenience - which doesn't stop degrading interaction occurring; but may blind one to that possibility ... . Optimum sound means minimal perceived colouration - I find the word "distortion" has much more grunt than "colouration"; you've got the issue right in your gunsights that way.

 

Frequency balance? I never think in those terms - the sound is either tainted, or it's not. If it's not tainted then "all the frequencies work" - because the audible characteristics match that of normal, live, everyday sounds.

We also conveniently label radio frequency rf! Why, because they each require their own design and layout techniques... As to interaction, most designs these days have elements of all 3, as I have said before the internet is full of information regarding mixed signal design and layout...

[marce]

8 hours ago, fas42 said:

 

I have never used USB, but I don't like what I see in the circuits which receive the data, and pass it onto the D to A converter - to me, the ones I have looked at all have flaws in the implementation - no wonder people are struggling to get this right!!

Explain, you have a transiever, one side USB, the other side the system, pretty much standard on any digital signal comms. interface.

[marce]

7 hours ago, fas42 said:

I used to read of the nightmares people were having getting good sound when the data had to be reclocked in the DAC,  just from a mechanical player - in the HiFi News mag. And the endless debates about strategies ... the jump from one box to the next is a weak link; simple solution, eliminate it ...

asynchronous data transmission with reclocking at the point of conversion is the best way to do it... local buffer with short data path and local well regulated clock.

[marce]

1 hour ago, fas42 said:

 

Let's get back to basics, shall we ...? Digital replay relies on data being sourced from some device - make it the man in the moon if you like ... theoretically now the only thing that counts is having an accurate clock driving the DAC to input that data, which we assume "always arrives in time", by some means - if everything is as electrically 'clean' as necessary, then we should be hunky dory ...

 

If the chain is as simple as one can make it, and we get excellent results, then we have "proven the case". If we then decide to complicate everything, for convenience, and extra flexibility - and immediately we lose the excellence we were able to get otherwise - then our 'extensions' don't have the integrity in their implementation that they should. And therefore all efforts should be focused on sorting out why the complexity has crippled the performance potential - just adding gizmos and extra bling in various areas "to fix it" is blindfold throwing of darts.

Or TV from a satellite, or the internet a medium where BS can be composed on the other side of the world and appear as if by magic on my screen.?

[marce]

2 hours ago, fas42 said:

 

Of course we're talking about the analogue characteristics of those waveforms - we've been here many times before . If the circuitry following, the analogue areas, was completely robust to the varying nature of those waveforms then the cable could be twisted bits of fencing wire, only needing the digital integrity to be maintained.

 

I don't understand, please explain, what do you mean the digital waveform or the analogue after the DAC... And if the digital waveform please explain what you mean by the analogue aspects of the waveform...

[marce]

2 hours ago, Richard Dale said:

Yes, that sounds correct to me.

 

With respect to your original comment, I think the protocol you really want is I2S where the slave's clock can actually control the timing of the transactions with the master, rather than just the flow control like isochronous USB. But then there is no agreed cabling standard for I2S.

Because it an interface that was NOT designed to go down cables, its a local on board bus, designed for limited distance.

[marce]

9 hours ago, fas42 said:

 

That the digital waveform has characteristics that are meaningful in the analogue sense, say, the rise time of the transitions - and all the conductors in the link may have various types of non-random noise present; that this ultimately impacts the following analogue areas of the playback chain. Yes, this shouldn't happen, and yes, it means the implementation of the analogue is not as robust as it should be; what I do is to keep making things more "robust" until the sound stops changing when I do more - I've reached the point where it's sufficiently 'debugged'.

You are not saying a lot, cables with non random noise! Do you have any understanding of signal integrity in regard to digital signals...

[marce]

9 hours ago, fas42 said:

 

I said conductors, not cables  - there is a difference ... .

 

And, you keep confusing digital with analogue - perhaps you should check out some textbooks, .

 

A cable is a conductor... please explain, a signal will travel down a PCB trace or a cable, both are conductors.

NO you said the analogue aspects of the digital signal. I have asked you to explain what you mean instead of snarky little replies with no content.

[marce]

On 9/26/2018 at 12:04 PM, lmitche said:

The simple point here is that digital signals are carried over an analog infrastructure and that whatever makes an analog infrastructure great for reproduction from analog sources also makes it great for reproduction from digital sources.

Nope...

[marce]

8 hours ago, fas42 said:

 

 

What I see are people obsessed with there being technical issues - requiring technical solutions. Ummm ... it doesn't work that way - achieving signal integrity in the analogue sphere isn't like a lovely programming exercise, that you can write a paper about. <Car analogy alert!> Rather, it requires looking under the hood and noting where poor workshop practices have made things far too twitchy - solve those issues, and all the driveability problems just fade away ...

https://www.amazon.co.uk/High-Speed-Digital-Design-Semiconductor/dp/0133957241

[marce]

12 hours ago, Superdad said:

 

Well there is one (rather general) statement that I think most here can agree upon. 

 

Nope I disagree, the circuitry and hows it laid out differs for digital, analogue,rf/microwave each has their issues and resolutions. High speed digital is high speed digital whether its audio (though the only high speed digital in Audio is the DDR memory interface, Ethernet and to some extent USB and if a motherboard the various on board busses, all covered in detail) or more taxing designs such as mixed signal boards with multiple high speed ADC/DAC's and some phase array microwave... Mixed signal design and layout is also well documented and again is pretty common in electronics in the wider world, so the interaction between the various sections (Digital, analogue, rf etc.) is again well documented and how to minimise such interactions...

[marce]

I think part of the problem is we look at the "digital waveform" as a voltage, if you look at it as the thing we are actually interested in the rise and fall slopes when all the excitement happens and look at the current pulses as well, you get a different perceptive on what digital transmission is, a monotonic regular current pulse that will result in a monotonic regular pulse that will cause a voltage rise at the receiver causing a defined switch of state... or not. DDR memory is best, never seen square... yet it works reliably.

[marce]

a comparator?

[marce]

You can have fun with them, with a couple and a bit of basic logic you can create a simple high low switch... A 1 bit DAC?

[marce]

10 hours ago, fas42 said:

 

Hmmm ... this is purely about digital integrity, when you are pushing the speed hard - zero about "mixed signal".

Do a bloody search for mixed signal, like I have said before, there is a lot of information, most boards I do are mixed signal these days. Usually every manufacturer of mixed signal devices (eg. DAC) will have a realm of info on layout, supplies, grounding etc. Read Henry Ott, Ralph Morrison, also understanding the digital side of things would give you an understanding of the issues the digital can cause the analogue side...

All mixed signal boards should be segregated, the digital in one section, main supplies in another section away from major signal paths, the analogue in its won area, minimal signal loops, minimal interaction, including importantly power/ground planes inadvertently coupling capacitivley...

[marce]

2 hours ago, fas42 said:

 

Sometimes one finds great amusement in what one comes across - just happened to look up Ott's Electromagnetic Compatibility Handbook - and noted the first sentences in the Mixed Signal chaper ...

 

 

Look at the dates, things move on...

Why do you always look for something to support the negative view, why not post some real info on how it cna be done, look for some of the positive information. Jeez if I worked like this I would never get a job done, because a lot look impossible when you start, so you don't go it can't be done, you start with reading the active devices data sheets and planning out the critical signal flows, both local to circuitry and accross the board between blocks of circuitry...

You don't look for reasons why it cant be done, that's giving in before you start.

[marce]

Here is your starter for 10, it's one of my go to documents for anyone wanting to learn PCB design

http://www.x2y.com/filters/TechDay09kr_hpa_Track2_1_Precision_Analog_Designs_Demand_GoodPCBLayouts _JohnWu.pdf

 

From the references:

http://www.hottconsultants.com/pdf_files/june2001pcd_mixedsignal.pdf

 

 

[marce]

5 hours ago, PeterSt said:

 

•  
• John Wu Vice President of Facilities Sde Business Partnering Llc
• John Wu Department System Analyst CSAA Inter-Insurance Bureau
• John Wu Chief Technology Officer Alibaba.Com Corporation
• John Wu Senior Vice President of Supply Chain, Merchandising and Global Sourcing Partsearch Technologies Inc
• John Wu President King Of Fans Inc
• John Wu Founder and Chief Executive Officer Perfect Lending Solutions
• John Wu Senior Oracle Database Administrator Michaels Holdings LLC
• John Wu Senior Systems Analyst-telecom Susan Davis International
• John Wu Information Technology Director Shihab & Associates, A Legal Professional Association
• John Wu IT Director The Rubber Manufacturers Association Inc
• John Wu Chief Office Of Quality Government of The United States
• John Wu Business Operations Manager Cisco Systems, Inc.
• John Wu Director of Engineering Cole Hersee Company
• John Wu K12 Teacher Kent School District
• John Wu Venture Partner Northern Light Venture Capital
• John Wu Senior Scientist Johnson & Johnson
• John Wu Chief Executive Officer Solar Power Industries, Inc.
• John Wu Environmental Manager Daimler AG
• John Wu Senior Unix System Administrator County of Santa Clara
• John Wu Director, Product Planning Boxwood Technologies Inc
• John Wu Systems Engineer Network Solutions, Inc.
• John Wu Faculty Richland College Dallas County Community College District
• John Wu President, Chief Executive Officer Digicon Corporation (US Headquarters)
• John Wu Loan Officer Direct Source Funding
• John Wu Isa State of Calif Government
• John Wu Operations Manager Silverwings Unique Inc
• John Wu Lead Of Quality Assurance Engineer Expedia, Inc.
• John Wu Sales Executive Coldwell Banker
• John Wu Senior Service Fellow United States Department of Health and H
• John Wu Chief Financial Officer Chapal Inc.
• John Wu Payments Product Manager TSYS Corporation
• John Wu Vice President Wu Enterprises Inc
• John Wu Tpm Amazon.com, Inc.
• John Wu President VIAWORLD ADVANCED PRODUCTS INC
• John Wu Senior Technical Support Engineer Attune Systems Inc.
• John Wu Network Manager The Agency Group
• John Wu R and D Special Projects Information Systems Moody Bible Institute
• John Wu Chief Technical Officer Alibaba.com Limited
• John Wu Chief Executive Officer Digicon Corporation
• John Wu Owner Ameditech
• John Wu Manager, Facilities, Environmental and Building Services Mercedes-Benz U.S. International, Inc.
• John Wu Staff Geophysicist TOTAL SA
• John Wu Owner Dependable Collision
• John Wu President Information Dynamics Inc
• John Wu Research Intern Carnegie Mellon University
• John Wu Scientist Pfizer Inc
• John Wu Credit Lending Club Corporation
• John Wu Product Manager Xerox
• John Wu Consultant The Boston Consulting Group
• John Wu Architect Citigroup Inc.
• John Wu Program Engineering Manager Northrop Grumman Corporation
• John Wu Vice President of Software Engineering Novatel Wireless, Inc.
• John Wu Software Architect Intel Corporation
• John Wu Auto Advertising Coordinator CHENG SHIN RUBBER IND. CO., LTD.
• John Wu Senior Director of International Tax Salesforce.com, Inc.
• John Wu Chief Executive Officer Global Strategic Connections
• John Wu Director And Professor State of California
• John Wu Associate Jefferies & Company, Inc.
• John Wu Consultant Citigroup Inc.

The man has many faces.

And still that is not him.

 

 

A quick search would find who he is... The fact its got Ti (Texas Instruments) all over the presentation would possibly give you a hint.

[marce]

21 hours ago, fas42 said:

 

2009? The latest book from the author you suggested I read, in the previous post ...

 

I was reacting to your comment that it was "well documented" - when in fact there is much material pointing out the common design errors made, and mistaken ideas clung to. IOW, it's not trivial to ensure an absolutely clean separation between the areas - and the USB link for audio seems to be a prime area for issues to arise, going by the number of, yes, negative comments about the performance of the standard design methods.

Disagree, do this every day, just recently done two boards with microwave (analogue), 24 bit DAC's, digital and SMPS's... work perfectly, USB is a doddle by comparison... But then this is audiophile audio so normal rules don't apply...

[marce]

6 minutes ago, PeterSt said:

 

I gave you guys his number ...

It's a TI telephone number, why?