Short AES Cable Runs - how bad is regular mic cable?
Posted:
Fri Apr 24, 2020 11:50 amby smash
Hey T-Rockers.
I need to run 4 x 5m AES XLR-XLR cables.
I know that correct technical spec is 110 Omn... and that it is absolutely necessary for long runs.
My question is, will there be any degradation in using regular cable - AKA Mogami 2549 (which I have a roll of) instead of the dedicated AES cable.
Cheers,
Smash.
Simon "Smash" Ashby.
Re: Short AES Cable Runs - how bad is regular mic cable?
Posted:
Sun Apr 26, 2020 5:49 pmby chrisp
* Should * be OK for short runs, AES and mic cables and connectors are pretty much identical. And in reality, there is no such thing as a digital cable per se, it is all analog voltages going over copper.
The cable losses in analog signals are a little bit of SNR lost to heat and frequency change due to (small) cable impedance. You fix with gain and EQ as required, but in most cases you wouldn't need to bother.
The cable issues for digital are different. Cables transmitting digital signals need to be able to provide sharp voltages differences to signal a '1' and a '0', and also 'transmit' impedance (the 110 ohm number) from the sending device to the receiving one (ie make each device think it is very close to the other one, even if they are far apart). Put another way, there is a relationship between distance and bandwidth reflected in cable quality, so when you buy a SDI video coax cable rated 12Gb/sec over 100m compared to cable rated at 3Gb/sec over 10m, you are buying a certain quality of manufacture and testing, if you like, rather than a different type of cable - they are both just coax cable. You buy the quality of cable needed to deliver the bandwidth you need over the distance you need to run. Hence sending AES digital signals using mic cables over short distances should be OK.
Re: Short AES Cable Runs - how bad is regular mic cable?
Posted:
Mon Jun 08, 2020 9:38 amby Alastair Reynolds
The spec for AES is pretty loose, 110 ohm +/- 30%, so short runs using mic cable should be fine.
Remember too CAT5 cable spec is 120 ohm +/- 10% which places its window well inside the AES spec and is very cost effective for AES wiring. Don't worry about CAT 5 being unshielded, the work is is all done in the twist. Shielding on CAT 6 is more to stop the noise from gigabit data getting out.