Film-Tech Forum ARCHIVE: AES Cable recommendations

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Posted by Danial Simmonds (Member # 4638) on 06-02-2010, 11:13 PM:

Hi Everyone!

Just want to look at your opinions on what type of belden cable is best used for the AES out from the server to the audio processor.

I have been looking at Belden 1800B and 9729...

Does each pair (channel) needs a ground? I think it does but remain uncertain.

Take Care
Danial.

Posted by Chase Taylor (Member # 778) on 06-03-2010, 06:03 AM:

Belden 1803F is what I use, I use the drain on each pair and then put the drain for the cable to the metal housing on the terminations.

Chase

Posted by Steve Guttag (Member # 268) on 06-03-2010, 06:55 AM:

1803F is also what I use (1800B is just a single pair, 1803F is a 4-pair snake).

Just remember true 110-Ohm cable is FAT as compared to its analog cousins so it is a tight fit into a DB25 Hood even though it is 24awg (1803F). There is a 26awg version that we are looking into. Especially, if the industry does go beyond the 8-channels already (and they sort of have since the VI/HI channel has been defined as 15/16)...getting 8 pairs in a DB25 is going to be REALLY tight.

Steve

Posted by Bruce Hansen (Member # 281) on 06-04-2010, 04:57 PM:

I have used Belden 9180 for short runs, like wiring patch panels, and DAs, with no problems. 9180 is the 26 AWG version of AES digital audio cable. It is about the same size as 8451. Trying to get 96 pieces of 1800 type cable into a patch panel is near impossible, it's just too big a wad of cable.

Posted by Stephen Furley (Member # 1277) on 06-05-2010, 03:16 AM:

quote: Steve Guttag
Just remember true 110-Ohm cable is FAT as compared to its analog cousins so it is a tight fit into a DB25 Hood even though it is 24awg (1803F). There is a 26awg version that we are looking into. Especially, if the industry does go beyond the 8-channels already (and they sort of have since the VI/HI channel has been defined as 15/16)

Do you have a list of all channels so far defined? In some special circumstances you might need even more channels; multiple languages for example.

quote: Steve Guttag
...getting 8 pairs in a DB25 is going to be REALLY tight.

And I still think it's totally unnecessary. If all of the channels are going to and from the same place, e.g. digital server to processor, it could easily all go down a single strand of co-ax as a single bitstream. If only the AES had defined a proper standard for the transmission of multi-channel digital audio.

Posted by Josh Jones (Member # 447) on 06-29-2010, 03:19 PM:

quote: Stephen Furley
And I still think it's totally unnecessary. If all of the channels are going to and from the same place, e.g. digital server to processor, it could easily all go down a single strand of co-ax as a single bitstream. If only the AES had defined a proper standard for the transmission of multi-channel digital audio.

You have to keep in mind that when the current AES protocol was defined, around the time of digital mastering and recording I imagine, the most that was needed was two channels. Its also a well established standard, used in the fields of recording and broadcast, as well as film.

FWIW, using Beldin 9728 here.

JJ

Posted by Steve Guttag (Member # 268) on 06-29-2010, 10:22 PM:

quote: Josh Jones
FWIW, using Beldin 9728 here.

Ahhh...ignorance is bliss...I guess. 9728 is not proper AES cable. Instead of 110-Ohm, it is 100-Ohm. It also has the extra "joy" of having deal with the individual foils. There is also no overall shield

I'm curious as to its performance on longer runs though I don't doubt that it will do okay on shorter runs. It has to be better than what I see too much of...1510C...which is 4-pair analog snake...impedance is only 50-Ohms

I'll stick with the correct stuff...1803F but I'm looking into 7880A for 8 pair and 7890A for 4-pair to cut down on the size a bit. Most of our digital runs are 50-feet or less...at least it is 110-Ohm cable. I don't know if I would want to go over 100-feet with it.

Steve

Posted by Josh Jones (Member # 447) on 07-01-2010, 12:20 PM:

Interesting as that cable is listed as a digital audio snake. I can't find any info on any standard that uses 100 ohm interfaces. If it isn't a true digital cable, what would it be used for?

JJ

Posted by Steve Guttag (Member # 268) on 07-01-2010, 08:01 PM:

Yeah...it is odd...in the catalog it is listed as a digital audio snake (AES/EBU even) but in the actual spec sheet...it neither has the AES/EBU listing nor the traditional attenuation specs for 100-feet.

Steve