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Can you get "audiophile" sound using a native RP4 USB port into a DAC?
#31
(04-06-2021, 09:59 PM)jonners Wrote:
(04-06-2021, 08:57 PM)Norbert Wrote: ....

.....BTW: In a german forum I read that someone heard a difference between the direction of an ethernet cable...

.....

Well of course. The  digits get used to going one way and doing that will make them all go back to front. Dodgy

And I am sure for Australia you need a different cable because everything is upside down.  Cool  
Plus I hope they took the coriolis force into account, too, because this also has an effect which shouldn't be underestimated. I am sure a different type of shielding is needed because the electrons in the cable are pushed into a different direction while being on the Southern part of the earth, so you need the exact opposite type of asymmetric cables they use for the Northern part in really, really expensive cables.
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#32
(04-30-2021, 11:29 PM)lolli8 Wrote:
(03-26-2021, 05:07 AM)Jandu Wrote:
(03-25-2021, 04:22 PM)hifinet Wrote: Even with a linear power .....

Different sound means different data. You can't change music without changing the underlying data which build the soinc waves and which in the end build the music.

Same data used on different DACs would give different sound, else, no one would make DAC that cost more than the basic one.  - different sound on same data

Same music can be coded differently and the purposes for different coding would serves different purposes, among these purposes, sound optimization is one of them. -same music different coding.

Sound quality is determined by many factors. Some better understood, some not as much. If you believe a different USB cable would change the sound, you would understand that it's not just the 0s and 1s that count.
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#33
(05-01-2021, 02:50 AM)Jandu Wrote: Sound quality is determined by many factors. Some better understood, some not as much. If you believe a different USB cable would change the sound, you would understand that it's not just the 0s and 1s that count.

Hi Jandu, short question: do you have any basic knowledge about physics and maths, plus some basic understanding of computers?

If it would be the case, you would immediately stop telling this nonsense, as soon as you had a look at how the data is transferred over an USB cable. In case you have the required skills (which I doubt), please check the wiki page about pulse density modulation which is the method used to transfer data over an USB port from a network streamer to the DAC.

It takes more than some random noise to have an influence on anything in the data chain here. And yes, all that count are the 0s and 1s, but to explain this a bit in detail you would have to understand maths like fourier transformation, which I also doubt you know what this is.

So please keep your religious aspects (I believe there is more than 0 and 1), but keep these ideas to yourself, so others don't waste money by buying snake oil like you did. At least I agree on one of your points: "some better understood, some not as much", with an emphasis on "not" on your end.

Sorry.
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#34
(05-01-2021, 06:13 PM)lolli8 Wrote:
(05-01-2021, 02:50 AM)Jandu Wrote: Sound quality is determined by many factors. Some better understood, some not as much. If you believe a different USB cable would change the sound, you would understand that it's not just the 0s and 1s that count.

Hi Jandu, short question: do you have any basic knowledge about physics and maths, plus some basic understanding of computers?

If it would be the case, you would immediately stop telling this nonsense, as soon as you had a look at how the data is transferred over an USB cable. In case you have the required skills (which I doubt), please check the wiki page about pulse density modulation which is the method used to transfer data over an USB port from a network streamer to the DAC.

It takes more than some random noise to have an influence on anything in the data chain here. And yes, all that count are the 0s and 1s, but to explain this a bit in detail you would have to understand maths like fourier transformation, which I also doubt you know what this is.

So please keep your religious aspects (I believe there is more than 0 and 1), but keep these ideas to yourself, so others don't waste money by buying snake oil like you did. At least I agree on one of your points: "some better understood, some not as much", with an emphasis on "not" on your end.

Sorry.

Woah what an arrogant answer, better hold your horses before you ridicule yourself more.

If you think it's you who know everything, then I've got bad news for ya. Not even the smartest men on Earth think that they already know everything about all physics that exist. On the contrary, they say that it's probably still more that we don't know than we know. 

And yet, YOU feel that you're entitled to belittle a person, who has apparently far more skills in building hifi systems than you and is willing to share some of his experience. 

The only one who sounds "religiously" - refusing any other ideas, rejecting discussion, attacking others because of opposing opinions (with emphasis on "opinions"), is you my dear.

If you think you're that smart, then explain me how is it possible that two sources, which pass the Bit-perfect test on a DAC, sound completely different, while the rest of the chain is left untouched? 

Next time, before you start behaving that disrespectfully, first try some things yourself. There is far more in shaping music than current, still limited human understanding can explain, some are just unable to imagine that. 

But in every period there are closed-minded people, who are not willing to accept anything outside their comfort zone. Then there are others, who are not afraid of experimenting and exploring unkown. Guess which these two group is more beneficial for the society.. 

Presenting digital music is more than 0 & 1s in a correct order, whether you believe it or not. Deal with it. 

Not sorry.
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#35
(05-01-2021, 09:38 PM)mxpwladimir Wrote:
(05-01-2021, 06:13 PM)lolli8 Wrote:
(05-01-2021, 02:50 AM)Jandu Wrote: Sound quality is determined by many factors. Some better understood, some not as much. If you believe a different USB cable would change the sound, you would understand that it's not just the 0s and 1s that count.

Hi Jandu, short question: do you have any basic knowledge about physics and maths, plus some basic understanding of computers?

If it would be the case, you would immediately stop telling this nonsense, as soon as you had a look at how the data is transferred over an USB cable. In case you have the required skills (which I doubt), please check the wiki page about pulse density modulation which is the method used to transfer data over an USB port from a network streamer to the DAC.

It takes more than some random noise to have an influence on anything in the data chain here. And yes, all that count are the 0s and 1s, but to explain this a bit in detail you would have to understand maths like fourier transformation, which I also doubt you know what this is.

So please keep your religious aspects (I believe there is more than 0 and 1), but keep these ideas to yourself, so others don't waste money by buying snake oil like you did. At least I agree on one of your points: "some better understood, some not as much", with an emphasis on "not" on your end.

Sorry.

Woah what an arrogant answer, better hold your horses before you ridicule yourself more.

Knowledge only looks arrogant if you don't have the required skills and you have to believe what others say. You will fail to understand where reality ends, and where the "snake oil" stuff starts.
If you don't believe me but think you have enough knowledge, do the following. Based on your response you should be clever enough.
1) Look up https://en.wikipedia.org/wiki/Datei:Puls...lation.svg . You can find a sample code written in Python. Take that one or translate it into the programming language you know.
2) Add second sinus wave with a lower frequency and a lower amplitude.
3) Run the program to generate the density-pulse data format (the 0 1 0 1... bit format). This is what your USB port is sending as data.
4) Go back to the program and change the amplitude of the wave you have added in step 2) and repeat step 3)
5) compare the output of the two formats and spot the differences.

If you want to change the sound in any way (doesn't matter if you call it quality, enhancement, "more clean"), then your cable or whatever equipment you use/exchange will have to modify these bits in exact the same way to achieve what I have done in step 3-5 by changing the underlying sound data. This is required because the DAC on the other end of the cable only translates digital data but not best wishes or high hopes. Same data leads to same results.


Now consider the following details: If you apply the bit corrections in the wrong place, you end up with chaotic sound, so you need to switch the exact correct bits in the right places.
These bits are send in the same frequency the signal was encoded, which is 2.8 MHz. You need at least a frequency with the same or even higher to be fast enough to apply the changes. Electricity has 50Hz and even the fastest switching "dirty noise generating" power supply is maxed out 1.6 MHz., but the switching frequency typically is in the range of 10-50 kHz.
There is zero chance to modify the data stream in a way like done, because there is no equipment in the data chain to do this, and any element which would be fast enough doesn't know at which point the data stream must be modified. This especially applies to USB cables without any computing power.

SO: any comment about the enhancements ("better bass") are simply classified in the same way like placebo. 
But please, prove me wrong. It's easy, only some lines of code.
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#36
You can repeat the same game with PCM (pulse coding mechanism) instead of Pulse density (used in the DSD format) and come to the same results.

But lets assume the absurde idea of an intelligent USB cable is real, and this cable (or a power supply) can change the data stream of the encoded sound in a way so it "gets better bass", without the need of first translating the data into the wave format, then doing a fourier transformation to be able to modify a specific frequency (range), run reverse fourier transformation to get the wave format and then do the encoding again (this is what a DSP does)....

the whole thing will fail as soon as you change the encoding mechanisms. If you switch from PCM to DSD or just change PCM 44kHz 16bit (CD format) to PCM 768 kHz 32bit or any other quality, the whole data format is different. Your USB cable doesn't know this and will produce chaos in such a case, because it will change the wrong bits now.


So if you can't write a program. Exchange the cable, or PSU, or whatever. Play a song with one encoding, check the output. Change the data quality of the output (can be done in Windows in the driver settings), play the same song. If you still can hear it, it's the 100% prove your USB cable didn't reprogram the sound, or your PSU.

Sorry if you wasted money on snake oil.
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#37
@lolli8 This topic is for friendly and respectful discussion of various opinions and experiences but your posts include personal attacks and look pretty trollish to me and I've got no patience for that.
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#38
(04-28-2021, 12:50 AM)rebbi Wrote: I recently received my USBridge and Shanti from Allo. I am using it with Moode via USB to my Vinnie Rossi DAC (L2, in a Vinnie Rossi LIO integrated amp). Once I've had the chance to compare the sound to my RP4 (via USB) to the same DAC, I'll post my impressions here.  Cool

Hi
After this threads slight detour I still hope to hear your opinion of the USBridge.
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#39
I will leave the discussion about placebo effects to the ones who want to believe, but as a data engineer and programmer I can only tell one thing: if there would be any dependencies/relation between what a computer produces as as digital output and the choice of simple hardware like a cable, we could forget to use computer at all. This does not only apply to USB, but any method to generate, store or move digital data around.

According to Allo I run the worst possible combination to generate the digital output. A cheap PSU for the rpi4, worth maybe 5 Euro. Wifi dongle attached to one USB port, SSD drive to the other and the USB cable going to the DAC is a no name thing with an unknown origin. I only know one thing: it's cheap based on the build quality. I am connected to the Moode web server over the wifi dongle and upload new files over an ethernet cable, which is also plugged in and connected to a Fritzbox 7490.

Worst case scenario, still no change in the quality. No noise, no scratches, blips, whatever. So either the DAC/AMP/loudspeaker combo I use is bad and I don't hear noise generated by the many other devices, or - as I mentioned first - the digital data is not changed at all. I highly doubt this, the combo is used by my wife to analyse classic music in her job, and she needs to be able to track single instruments in an orchestra for this.

As said: IT wouldn't be possible if digital data and data manipulation couldn't be reproduced across different systems. But's it is not my money.
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