Digital Signal Transmission

[TomJ]

1 hour ago, fas42 said:

 

Because it is hard to give meaningful measurements - its effects could be measured, but no-one has clear ideas on what precisely to measure. On the cause side, it would be possible to make all sorts of measurements of various types of noise; but actually pinning any of these measurements on what is subjectively heard would be difficult - one could wave one's hands and say that the lowest numbers are probably going to mean the best performing device; but this would just be guessing.

 

I thought the effects could not be measured, only heard?

 

But when a company begins to develop a device, it has to define the goals - if that's just "improving sound quality" and you're just messing around with the try and error method, then I can understand the high prices, but also the professionalism and traceability is doubted and people like Amir are most welcome.

 

For example, for a network switch (sorry to overemphasize this topic) at least two things must be achieved:
- Noise reduction - could be measured
- Data integrity - could be measured

Maybe there are a few other things that I am missing, but at least these two points are widely accepted.

 

For example, I don't think an audiophile switch has any higher data integrity. However, this would be very easy to prove with a simple measurement by the manufacturer. But maybe one is afraid that this is not the case.

 

I also doubt, for example, that the noise level will be lowered that much compared to a standard switch with LPS. That would be easy to prove. But I always only get the answer, I have to believe it and trust my ears.

If the producer could prove something here, they would have more customers. Do they not want this?

 

 

[TomJ]

2 hours ago, PeterSt said:

 

Sadly, No. There is no such thing as noise to be measured in the context of audio data, as the HF protocol frequency data *is* noise to the audio domain. There's really nothing to measure there.

 

 

Another No; data integrity in this realm is nothing else but an eye sufficient open so no errors are produced.

Far away a more open eye could imply better sound, but it won't work out like that at all. Besides, you are still too early with these measurements because you need to be in the DAC, right at the input of the clock signal next to the D/A element (usually a chip). And again no noise is really to be measured there because it is about jitter. Of course, following my own explanation it *is* about noise super imposed on the clock signal, but where the clock signal is 22MHz already (or double that or more), the noise is a multitude and not anything easy to measure. So ... this is not how we measure noise ... we again measure/observe an eye diagram, which is not even in order at that (clock signal place) because ... that again is wrong and has to be about "data" (of the i2s protocol in this (general) case). That data contains the clock signal too.

 

Now Paul, come on. You say that all these things can easily be measured. Now teach me how (but bring some money please, if required).

;-)

 

OK - just pulled the trigger for this amazing new invention: Quantum Stickers.

Will stick them on all the parts of my switches, routers, servers, streamers and DAC and im done! 🤣

https://telos-audio.com.tw/sticker/

 

 

[TomJ]

Just now, pkane2001 said:

 

You're learning fast! ;)

 

And bought some audiophile stuff to prevent jitter during listening in my brain:

[TomJ]

4 minutes ago, MarkusBarkus said:

@TomJ if your are putting Quantum Stickers on internal components, I predict you will NEVER be done tweaking! 😉
 

Wish they had some stickers with quantum Smurfs or quantum dinosaurs...

 

 

Would be a nice job to do A/B test witch these stickers. Once you are done with sticking, you will be so amazed to here your system again, even if the sound get worse, you cant remember how the sound was before.

[TomJ]

20 minutes ago, fas42 said:

 

Can a doctor prove to you that the medication that he prescribes for you will solve your pain issues, by quoting what the manufacturers test results were? I'm afraid in the murky world of audio there are so many variables, that feeding you with numbers might make you feel more comfortable - but has little to do with guaranteeing outcomes.

My hobby is not to look at numbers - I dont wont to spend my time in testing thousands of devices in thousands of combination. and when i am done to hear from someone else there is a 1001th device to test.

I want to hear music in the finest way.

Its like pkane2001 mentioned: its like in the middle age.

 

The whole thing reminds me of a story from my studies. I really wanted to use a radiosity program that was only available for linux. Since I wasn't a Linux user, I went to the Linux group at my university with the hope of getting help. But these guys weren't interested in helping me and sharing their knowledge. Instead, they felt cool to have a knowledge that others don't, so they made a big secret. I just thought "fuck you linux-nerds" and got myself a program for Windows at great expense.

However, there is still a difference here - I trust the Linux nerds to know what they are doing. Here with the audiophiles, I'm starting to doubt it. 

[TomJ]

-

[TomJ]

I think with this story the musician should be the one who prepares the meal and the result is a matter of taste. But the scientist can determine the quality of the ingredients.

[TomJ]

8 hours ago, sandyk said:

That has been your assertion right from your very first post. So why are you REALLY here ?

It's certainly NOT to learn from the experiences of others.

I am here get answers to the question wow digital signal transmission can change the sound and where.

So I learned, that the sound can only be changed while converting from D to A inside the DAC. And that network devices can not change the sound, but influence the converting. This is done by electrical noise from the network device over the electrical path. Jitter problems in Switches has nothing to to with worsen sound quality directly, but can produce more electrical noise.

I learned, that an Isolator do not block all the noise, just a percentage.

But if I prevent noise coming in the DAC and data is send correctly, the network is no longer a problem soundwise.

Right?

[TomJ]

43 minutes ago, sandyk said:

No. It can also  be changed by the PSU area of the source due both to the components used in the PSU itself, but also as Peter has explained by different software loading of the PSU area. Even the external PSU used to power Regens and switches etc. can change the sound qualities to some extent, which is why some members daisy chain ultra  low noise LT3045 voltage regulators in order to increase apparent HF detail. This is due to the output impedance of these types of  regulators being much lower at >100kHz than in the lower frequencies.

I mean only during the conversion of D to A, or then in the analogue chain. The conversion is influenced by HF of PSU entering the DAC. But before conversion, there is no sound alive to change😀 - only data (and electrical noise/HF) and with TCP/IP and USB we get the data without manipulation into the DAC.

[TomJ]

7 hours ago, sandyk said:

 Your reply is from your closed minded perspective. In  fact, the PSU area of the source, including the PSU area for the SSDs  can also affect Digital Video the same way that it affects Digital Audio, just as the same data on SSD and HDD can sound a little different, even when played directly from System Memory. I am also able to demonstrate this to those who have a decent internal video card and a good quality external monitor, as well as a better than average main system.

 I have previously had my PSU reports in this area verified with a series of 6 separate DBT sessions with results publishd in HiFi Critic Vol. 6 No.1

 It is becoming increasingly clear that you came here only to TROLL, and not learn  from the  listening experiences of members here.

Neither are you interested in any of the proof that Peter , who BTW, is the designer of one of the most highly acclaimed DACs commercially available, as well as the highly respected XXHE S/W for Windows,(http://www.phasure.com/)

went to a lot of time and trouble to provide.

To remember:

This is in the Objective-Fi arera of the forum - not in the Subjective-Fi area. So subjective impressions you can share all over net, but not in this area. I only whant to find objective answers how the digital transmission can make digital data sound different.

If this is trolling, than this area should be renamed in something like "esoteric hifi conspiracy theories".

 

If data arrives correctly at the point of use (DAC) and a sound change still takes place, then I come to a conclusion that the sound change can only take place during or after the D to A conversion - serious and objective.

If you can contribute something in this way instead of constantly postulating your subjective impressions here, then that would be helpful.

[TomJ]

45 minutes ago, manisandher said:

 

For those of you who don't know, this is what happened:

 

1. I was absolutely convinced that I could hear real and obvious differences between bit-identical playback

2. I was confident that I could demonstrate this in a blind ABX

3. I invited @mansr to my place (even paid for his train ticket) to help me conduct an ABX in good faith

- Mans was in my office controlling the playback software (using the random generator on his phone to determine A/B)

- I was in my listening room across the corridor

- we captured the digital input to the DAC in real time to ensure that the 2 playback means were indeed bit-identical

4. I scored 9/10 in the ABX (1% probability that I was guessing)

 

Mans wasn't at all happy with the result, as it didn't accord with his belief that all bit-identical playback must sound identical. He suggested all sorts ways in which I might have cheated in the ABX, but even after looking hard for it, found no evidence for this at all. [Of course I hadn't cheated.] One of his suggestions was that I heard the keyboard strokes as he controlled the playback software from my office. Yes really... that I could hear keyboard strokes from another room, with two well-sealed closed doors and a corridor between us... AND decifer the keyboard strokes correctly! Absolute madness.

 

After the ABX, I sat Mans down in the listening room to demonstrate the differences to him. Though they seemed pretty obvious to me, he said that he couldn't hear them. Couldn't, didn't want to or couldn't because he didn't want to? Who knows.

 

All it would have taken was an open mind on his part, and we might have been able to come up with some interesting ideas for figuring out what's really happening.

 

My conclusion? What is sorely missing from the 'strict objectivist crowd', here and on other forums, is a dose of Russell's Critical Undogmatic Receptiveness. They espouse the scientific method and yet are incapable or unwilling to adopt the true attitude of science.

 

Mani.

So I agree with you that science is more than just measuring. But this also includes to consider that there can also be autosuggestion cases. In too many forums, people describe their elaborate mods - and yes, of course, they always sound better.

 

I believe in the measurement results of Amir, but I can also hear differences in the digital transmission.

 

For example, I have just replaced my network isolator, which caused a very good sound improvement on my KEF LS50, against another model. The result of the new model is not so good. But what is the reason for this? This is the question we have to ask ourselves in order to objectify the whole thing a bit. 
The old insulator has a strength up to 5 kV, the new one has only one of 4 kV. Perhaps a rule can be derived from this. I would like to see more of such attempts to explain what we have heard.

Here is a blind test regarding network switches.
https://www.alpha-audio.nl/review/zeven-switches-voor-streaming-audio-getest-blind/

If one makes hearing comparisons of network switches, then it would be helpful nevertheless if one tries to understand, where this is because of. I now believe that you can hear differences here (due to noise, RF affecting the conversion), but what is the reason? Is the positive effect of a switch by lower noise canceled out by an isolator?

 

Tom