|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
85.19.92.6
In Reply to: RE: Coax versus twisted pair. posted by Jon Risch on April 21, 2015 at 20:47:30
Hi Mr. Risch,
thank you sincerely for the very valuable advice.
Even if i am very uneducated this makes a lot of sense to me.
However, i still have some big doubts.
Let me elaborate a little.
One thing that i have learnt here is that digital signals transmission is usually a very challenging task.
So i am doing a weird reasoning.
If this task is more demanding that the transmission of an analog signal why good digital cables (usually coaxial) cannot be also good for analog signals ?
Moreover one of the most challenging situation is the connection from a scope probe to the scope.
So a cable good for a scope probe should be also good for digital connections (impedance issue solved) and then also for analog connections.
But i guess i am trivializing a lot.
There could be something more decisive involved.
Thanks a lot again for the very valuable advice.
Kind regards,
bg
Follow Ups:
Your logic chain is not completely valid.
Oscilloscope cable use is not the same criteria as digital cable use, which is not the same criteria as analog signal use.
Without going into all the nitty gritty, as this would take some time to do, and I have posted many posts on audio cables and the theories behind the quality issues, I will give one set of examples for comparison.
In the case of an SP/DIF digital connection, the factors that make for good clean transmission of digital data are different than those for analog signal transfer.
For instance, the main factor for a digital cable is helping to maintain a low jitter signal environment.
This requires tremendous bandwidth, well above the fundamental data transmission frequencies centered around 5 MHz, good shielding and freedom from external noise and interference, and a controlled impedance
environment.
Analog signal transfer has a different set of important factors, good signal resolution at extremely low levels in the uV region, while digital needs to be clean in the middle of the bi-phase signal waveform, where the accurate timing detection of a signal polarity flip is paramount, that occurs around the middle of a 0 to 5 volt range.
Analog does not need a 60 MHz bandwidth or higher to convey high performance audio signals.
Analog signal transfer does not require strict and consistent impedance conditions at the source, along the cable, or at the load.
There are many other factors that come into play for each type of cable, but to say that a cable that performs well for digital or scope use will also perform well for analog signal transfer is an erroneous idea.
Jon Risch
Hi and thanks a lot again.
I was looking for a free meal ... almost let's say.
Because making a good digital cable appears quite straightforward to me.
I nice coaxial (like the Belden or VHAudio ones) and a decent pair of RCAs is what is needed.
But i have not carried-out many comparison for digital.
Instead i have tested many different analog Ics in the same system and i have been amazed by the differences.
With some Ics the sounds were all disconnected, while the good Ics put everything in order, like when focusing with a lens.
The fact that cables fascinate so many people i think it has to do with these effective differences perceived during the listening.
Thanks a lot again.
Kind regards,
bg
Edits: 04/23/15
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: