I would suggest you look at why we use digital , why analogue sensors transmit digital data, why analogue systems such as 4-20mA are not used any more. Look at the resistance digital has to noise, the switching point on digital is not at one point for a switch from a high to a low logic level as this illustrates..
https://learn.sparkfun.com/tutorials/logic-levels
I am afraid that what Sy has stated is true, there have been long discussions on digital cables having an effect on the sound, but taking noise pickup out of the equation, it is IMPOSSIBLE for a competently specified cable to alter the sound in such a way. A cable will either work or it will not and if it doesn't it will be very apparent as there will be drop outs etc. To change the sound to such a minor extent would require the bit pattern to be changed and specific bits only that carry the audio information, not the rest of the data packet.
😀..
Here is one of mine I have been doing it for years.. 20+
Also look at XLO cable as another example..(interconnect)
Nothing special about the idea its like a twisted pair (but different..)
Its called cross over cancelling <<as we called it..called wire transposition on the link..
http://en.wikipedia.org/wiki/Twisted_pair
If it doesn't work why bother doing it inside Cat cable..NB we didn't have cat when I started doing it..😀
Its been used in many different ways..one is to use twisted pair and transposition of twisted pair in the same interconnect..
Then the "nonsense bit" (or is it) silver plated cables and cross section..no further comment.
One more link:
https://www.google.co.uk/search?q=xlo+cables&biw=1391&bih=636&source=lnms&tbm=isch&sa=X&ei=JUxbVY6wE8raU9_ZgdAO&sqi=2&ved=0CAcQ_AUoAg#imgrc=4zWhLRihPM5ndM%253A%3BV3t2GS8vEGcfKM%3Bhttp%253A%252F%252Fwww.xloelectric.com%252Fwebyep-system%252Fdata%252F4-1-im-ProductImage-2767.jpg%3Bhttp%253A%252F%252Fwww.xloelectric.com%252Fitems.php%253FWEBYEP_DI%253D1%3B550%3B300
Regards
M. Gregg
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Before Cat cable came along, Ethernet was a co-ax cable with BNC connectors, with T-junctions.
Twisted pair does work best with proper differential signalling, differential routing and differential receivers, for single ended such as SPDIF the best option is co-ax for avoidance of noise pick up and signal integrity as long as the shielding is done correctly. But for most slow speed digital (without silly rise times) a piece of wet string will suffice...
The interesting thing is that as well as the telegraphers equations Mr Heaviside also gave us the twisted pair back in the 18th century.
Twisted pair does work best with proper differential signalling, differential routing and differential receivers, for single ended such as SPDIF the best option is co-ax for avoidance of noise pick up and signal integrity as long as the shielding is done correctly. But for most slow speed digital (without silly rise times) a piece of wet string will suffice...
The interesting thing is that as well as the telegraphers equations Mr Heaviside also gave us the twisted pair back in the 18th century.
Looked up XLO...
XLO Integrated Field-Balanced Surface/Diving Winding Geometry...
That is one mouthful🙂
XLO Integrated Field-Balanced Surface/Diving Winding Geometry...
That is one mouthful🙂
Thank for your answer.
I already tried the Belden 1694A cable and Canare RCA that are reputed and sattelite cable also without being convinced.
I agree with you and I am well aware that the market of cables is often a scam.
I will not pollute longer this topic with my cable story , it is not the original subject . Thank you for everything !
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Spdif Biphase mark code:
The bits are transmitted as such but are first encoded by bi-phase modulation
mark, which, instead of coding levels '0' and '1' by voltages, code information to
by phase reversals. In the bi-phase mark modulation, each bit is delimited
left by a phase inversion. If the transmitted bit is '1', a phase inversion
additional is generated in the middle of the clock period.
--> The underlined words are the main characteristics of the signal may be affected by the cable and which can be heard: loss of focus, aggressive treble, digital sound.It also depends on SPDIF receiver and its pll.
I forgot this:
Since the signal always has at least one phase reversal per bit transmitted , the
receiver can extract the encoding clock
-->This is the major problem.
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I did not know this cable brand, thank you for the links.
It's reminds me the Kimber cables.
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Spdif Biphase mark code:
The bits are transmitted as such but are first encoded by bi-phase modulation
mark, which, instead of coding levels '0' and '1' by voltages, code information to
by phase reversals. In the bi-phase mark modulation, each bit is delimited
left by a phase inversion. If the transmitted bit is '1', a phase inversion
additional is generated in the middle of the clock period.
--> The underlined words are the main characteristics of the signal may be affected by the cable and which can be heard: loss of focus, aggressive treble, digital sound.It also depends on SPDIF receiver and its pll.
No, and if so how does it affect the sound, this is raw data that has to be converted it is either a 0 or a 1 at the reciever!!!! Its a form of Manchester Encoding. Though for transmission the encoder does depend on the signal transition and does switch in the middle at the phase change point, my mistake earlier I was jabbering about on board logic.
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Kimber use the same idea..
The idea is its not so much the signal that's the problem..
The idea is to have a similar effect to the ferrite without using a ferrite..<<
Audio quest were eclipsed by the XLO when it came in in the 80's
I have tried lots of different ideas..(Built)
I have seen many different ideas in industry as well however..
Keep having fun..if it works for you great..
I have also used jewellery silver in cables and many other ideas.
One word of advise leave mains supply cables alone unless you have a background in EE.
NB the amount of Mush on the supply ground is quite surprising..
Regards
M. Gregg
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No. It would need to be a very bad cable to turn a 0 into a 1 or vice versa. A poor cable can cause high frequency jitter, but the PLL in the receiver should fix this. DIY cables are often quite poor. When people claim that their cable improves the sound they are eitherkillmister said:
1. mistaken - it hasn't made any difference at all
or
2. mistaken - it has added extra jitter which if big enough may be audible
DDDAC . Doede's first. Brute force approach with stacked 1543's. HF output stepped like a perfect set of stairs - Laughable! But the thing sounds great. Most musical dac I've heard.
The link explains (among others): the SPDIF clock is analog
http://peufeu.free.fr/audio/extremist_dac/spdif.html
"
The clock signal carries its information not in the logic levels but in the precise timing of their transitions (aka. "significant instants"). In this sense, it is an analog signal, as the timing information is defined by comparing the analog value of the clock signal with a fixed threshold and marking a clock tick every time the value crosses the threshold. Hence, it is very sensitive to noise and other alterations :
http://peufeu.free.fr/audio/extremist_dac/spdif.html
"
The clock signal carries its information not in the logic levels but in the precise timing of their transitions (aka. "significant instants"). In this sense, it is an analog signal, as the timing information is defined by comparing the analog value of the clock signal with a fixed threshold and marking a clock tick every time the value crosses the threshold. Hence, it is very sensitive to noise and other alterations :
- Noise added to the clock will shift the transitions.
- Low-pass action by cables and other circuitry will soften the edges and render them more vulnerable to noise.
- Low-pass filtering will allow other signals (like data) to contaminate the clock."
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This is non-oversampling DAC, the best i had heard too and the closest to analog which remains acceptable vs to a good vinyl 😛
The clock and the SDIF interface is a digital signal, you are reading this wrong and attributing analogue attributes to a digital signal transmission system and the waveforms generated, we have had this argument in great detail on other threads. What Peufeu is referring too in a very simplified (and slightly marketing😀) way is one of the mechanisms of how jitter is added.
I believe you are attributing analogue artefacts to a digital signal transmission such as waveform changes and correlating them to the sound.
All digital can be viewed as analogue but it is irrelevant for this discussion and only detracts from understanding what is happening.
Also SPDIF is not just the music, bits are used to indicate what the data is for (L or R etc.) as this shows:
http://www.minidisc.org/manuals/an22.pdf
So again the cable would have to be specific in what bits it alters, this is the realm of DSP and is beyond most cables.
here is some further reading that may help...
http://www.diyaudio.com/forums/digi...asuring-square-wave-spdif-cable-possible.html
And here with some simulations pictures...
http://www.diyaudio.com/forums/digital-line-level/194767-s-pdif-termination-practical-guide.html
Have fun...
And remember digital IS analogue, but we don't have to worry about it at this level🙂
Wax cylinder
Tape/Cassette
LP
CD
Streamed
All are flawed, I just enjoy the music these days, preferably with as much fidelity I can afford achieve... and don't worry. None of my systems are perfect, in fact I would describe one a defiantly flawed (LP via Tube amp (Class A SET) and FR speakers😉) but I love the sound it produces😀😀😀
The PLL in the SPDIF receiver deals with HF jitter, which is what the cable introduced. The fact that rather poor DIY cables can still result in reasonable sound is evidence that SPDIF PLLs are generally good enough. The piece linked from post 153 seems to confuse the raw clock with the cleaned-up clock, or hopes that the readers will be confused.
LF jitter comes from the crystal clock, and is likely to be much better than LP speed stability - some turntables used a crystal clock.
LF jitter comes from the crystal clock, and is likely to be much better than LP speed stability - some turntables used a crystal clock.
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