Topic: Digital cable vs. Analog cable ?

[TheImplodingVoice]

Hi, does anyone know if there is a difference between a Digital cable and an Analog cable?
For example, 75-ohm RCA coax comes in Digital or Analog, yet I've read either works for either application.
There are also Digital XLR cables.
BNC cables are for video, yet the Sound Devices 722 and other SD recorders have BNC Digital Audio inputs. Nick at Sound Devices told me
over the phone that I can use a Video BNC cable on this Digital Audio BNC jack of the recorder. Am I missing something?

Many thanks,
Tom

[Lil Kim Jong-Il]

No you aren't missing anything.  Yes, there is a difference and matching the cables to the application is important for long runs and is generally the right thing to do.  But inside one of our gear bags it isn't much of an issue.  I've used regular audio cables (standard grade cables with rca for spdif and xlr with canare mic cable for aes/ebu) when I needed to get something working in the field and I've never had an issue.

Nick is correct, 75ohm unbalanced digital audio cables and 75ohm video cables are interchangeable.  For short runs an unbalanced audio cable will work fine.

The balanced digital cables are typically 110 ohm but for short runs a short microphone patch cable will transfer the signal fine.

[TheImplodingVoice]

Thank you very much. Does anyone know if I need a Male BNC plug or a Female BNC plug for my Sound Devices 722? I believe i need a Male, but I'm just double checking.
-Tom

 

No you aren't missing anything.  Yes, there is a difference and matching the cables to the application is important for long runs and is generally the right thing to do.  But inside one of our gear bags it isn't much of an issue.  I've used regular audio cables (standard grade cables with rca for spdif and xlr with canare mic cable for aes/ebu) when I needed to get something working in the field and I've never had an issue.

Nick is correct, 75ohm unbalanced digital audio cables and 75ohm video cables are interchangeable.  For short runs an unbalanced audio cable will work fine.

The balanced digital cables are typically 110 ohm but for short runs a short microphone patch cable will transfer the signal fine.

[John R]

male.  speak to ed at kindkables.  he'll get you set up with what you need.

[fmaderjr]

DSatz always knows what he's talking about....

... for ordinary 3- or 6-foot S/P-DIF connections at ordinary sampling frequencies, no special kind of cable is required; ordinary audio cable will do fine. A cable shorter than about 1/8 of an electrical wavelength has no meaningful "characteristic impedance" so that whole issue is completely meaningless.

If you're going to use long cables or high sampling rates, look for 75-Ohm video cable with RCA connectors on it. Again, nothing expensive or exotic is required--just a Sony RCA-to-RCA video cable for $6 or whatever.

--best regards

[TheImplodingVoice]

Thank you both for your replies. This makes purchasing the cable easy and I know it will serve its purpose.
have a good day,
Tom