Quote:
Originally Posted by hum-free  Hey, thanks for your comment! That's what I expected. But what I don't understand is:
How can a firewire (or USB) cable affect the sound then? It carries a digital signal, so I would expect no signal change there, too. But there are some "Hi-End" firewire cables out there that are said to improve the sound... How can a digital signal be improved??
Greetings
Hum-Free |
Quote:
Originally Posted by Elk A cable can affect the signal if it impacts the timing of the data and perhaps other physical characteristics.
There are varying opinions as to whether this is audible. |
As long as there are no
errors in a digital signal transmission, the sound will
not be affected.
Digital signal transmission uses what are essentially on-off signals to transmit data. The difference between the on and off signals is extremely easy to read correctly -- unlike low level
analog signals, which, to transmit the signal correctly, must cover a broad range of frequencies and signal levels.
One area where problems arise in digital is when folks use improper cables -- particularly cables that are "out of spec" -- the engineering standards committees have determined safe cable lengths for digital and which, to avoid error, should not be exceeded.
But some of the very "boutique"/"magic" cable vendors that try to hawk snake oil to audiophiles have stuck their greedy hands into the digital arena, too, and in years past you've actually seen things like one vendor of digital leads (costing in the hundreds) that claimed "longer" is better in digital -- in complete contravention of established science. (Because of the very high effective signal frequencies of digital audio transmission, a digital cable that is too long for its specified purpose can end up with signal reflection that can lead to increased jitter.)
Here's a discussion thread led by converter design legend Dan Lavry which explores a number of digital signal mythologies, while focused on the (rather obviously bogus) claims of a boutique cable vendor:
PSW Recording Forums: Dan Lavry => Why longer is generally better for an S/PDIF Digital Cable [The title was drawn from the marketing materials of the boutique cable guy -- Lavry's position, along with others in the digital know, is that
shorter is better with regards to such cables.]