|
 Kyma Forum
 Kyma Support
 AES/EBU problem
|
| next newest topic | next oldest topic |
| Author | Topic: AES/EBU problem |
|
Bill Meadows Member |
posted 20 January 2001 13:11
 
I am having a problem with AES/EBU on my Capy-320. I had been using S/PDIF with all of my equipment, including the 320, with no problems. I recently purchased a MOTU-1224 which only has AES/EBU, so I decided to test that out with my other equipment. Everything except for the 320 works just fine through standard-grade, 18 foot long microphone cables. (Here "everything" means MOTU-1224, TC Electronics M-2000, Eventide DSP-4000 and Kurzweil K-2500.) I tried many combinations, including different cables from different manufacturers, and going directly from the 320 to each other piece of equipment. The result was that the 320 would only work through a short (5 foot) cable. This was true for both sending and recieving - the 320 output wasn't recognized (e.g. - "AES/EBU BAD" on the DSP-4000 display) and the 320 could not recognize incoming clocks from other units when it was set to "Digital Input". The 5 foot cables eliminated these problems in both sending and recieving directions. Unfortunately, it is impractical for me to place the 320 within 5 feet of everything else. Am I missing something? It seems that the 320 is at fault here, as all the other equipment works just fine. Do I need to expensive "specialty cables" for the 320? IP: Logged |
|
SSC Administrator |
posted 20 January 2001 16:42
Since you were using SPDIF successfully it suggests a possible grounding problem in your studio. The major difference beween SPDIF and AES/EBU is that SPDIF is an unbalanced signal and AES/EBU is a balanced signal. This means that the SPDIF cable was providing a ground path between your Capybara and your other gear. Since AES/EBU is balanced, there would be no ground path created. Could it be that all of your other gear is connected to one wall outlet and the Capybara (and your computer) are connected to another? This could cause a ground loop which could add noise to the AES/EBU signal. IP: Logged |
|
kelvin Member |
posted 20 January 2001 19:45
Hi Bill, I don't know if this helps. Are your 25 ft and 5 ft cables made by same company. As in same wire. From years of playing with different wires for digital transfer, I have run into many problems with the capacitance of the cable. Which gets worse the longer the cable is. This is like putting a cap across the line and the bigger the cap the lower the freq. cutoff. Some peices of gear seem to be more sensitive to this than others. It well round the edges of the data waveforms. I finally started making my own. And for SPDIF I use RG58 cable. That's TV coax. Which is very low capacitance for hi freq.transfers. I have been able to find some that is very flexible like audio. But this is 1 conductor and sheild unlike, as you probably know, mic cable is 2 conductor and sheild. But maybe you could try to find a mic cable with hi cap. like an audiophile grade, Monster, etc. and see if that takes care of it. Hope this helps, IP: Logged |
|
nkf Member |
posted 20 January 2001 23:53
Bill Meadows wrote: >>>This was true for both sending and recieving - the 320 output wasn't recognized (e.g. - "AES/EBU BAD" on the DSP-4000 display) and the 320 could not recognize incoming clocks from other units when it was set to "Digital Input".<<< If I understand all you wrote correctly it seems you are using wrong cables. You mentioned mic cables but AES/EBU cabling should be done with 110 Ohm cables. Nirto Karsten Fischer P.S.: (Kelvin) S/PDIF cables are not RG58 (50 Ohm) but RG59 (75 Ohm). IP: Logged |
|
sm Member |
posted 21 January 2001 09:23
i am using s/pdif for digital I/O. when i got the 320 it took me a while to find out thet the adaptors for teh AES/EBU to s/pdif conversion where not soldered correctly. there was no connection to ground. so for me it would be no wonder if there would be any hardware problem to the aes/ebu connectors. IP: Logged |
|
SSC Administrator |
posted 21 January 2001 12:35
Michael, As I told you when you first reported this, we discovered that one of our suppliers had shipped us a small number of mis-wired S/PDIF connectors in fall 1999 which we immediately stopped using (we also switched to a new supplier). The missing ground connection was not critical (i.e. it would not cause the S/PDIF to stop working, but it could make it less reliable under some conditions). It was impossible for us to know who received these adapters, but anyone who reported a problem to us got an immediate replacement set of adapters. These are just adapters and just for S/PDIF. They have absolutely nothing at all to do with the AES/EBU interface! IP: Logged |
|
Bill Meadows Member |
posted 21 January 2001 15:27
quote: All equipment is star-grounded back to a single line conditioner.
quote: Well, agreed. But it still begs the question of why these three 18 foot cables work fine for AES/EBU between four other pieces of equipment, from four different manufactures. (MOTU, TC-Electronics, Eventide and Kurzweil) The only AES/EBU "specialty" cables I have found are $60/cable. I was hoping for a less expensive solution. (I have had 100% sucess running S/PDIF up to 18 feet through standard audio-quality patch chords - luck?) How far should I be able to run AES/EBU with the correct 110-Ohm impedance? IP: Logged |
|
nkf Member |
posted 21 January 2001 18:22
Bill Meadows wrote: >>>Well, agreed. But it still begs the question of why these three 18 foot cables work fine for AES/EBU between four other pieces of equipment<<< You were lucky then - I cannot understand why you want to save pennies here while you have such a delicate system like Kyma? IMO 10% of studio cost should be seen for good cabling (correct specs/mechanical quality). There is no need for 'Monster' (Cable)-Madness. I like especially Mogami Neglex 3080 cables which are easy to handle (flexible). Usually I let mine assemble with good Neutrik connectors. I know from experience that a lot of machines work with 'false' cables due to the fact that manufacturers take wrong user attitude into account. But it should be avoided because sooner or later you will get a problem with wrong digital cabling. This is not a try from my side to defend all this 'esoteric' cabling BS a lot of 'audiophiles' are proposing. >>>(I have had 100% sucess running S/PDIF up to 18 feet through standard audio-quality patch chords - luck?)<<< >>>How far should I be able to run AES/EBU with the correct 110-Ohm impedance?<<< Nirto Karsten Fischer IP: Logged |
|
Vance Galloway Member |
posted 25 January 2001 07:49
[QUOTE]Originally posted by nkf: [B]Bill Meadows wrote: >>>Well, agreed. But it still begs the question of why these three 18 foot cables work fine for AES/EBU between four other pieces of equipment<<< You were lucky then - I cannot understand why you want to save pennies here while you have such a delicate system like Kyma? IMO 10% of studio cost should be seen for good cabling (correct specs/mechanical quality). There is no need for 'Monster' (Cable)-Madness. I like especially Mogami Neglex 3080 cables which are easy to handle (flexible). Usually I let mine assemble with good Neutrik connectors. I know from experience that a lot of machines work with 'false' cables due to the fact that manufacturers take wrong user attitude into account. But it should be avoided because sooner or later you will get a problem with wrong digital cabling. This is not a try from my side to defend all this 'esoteric' cabling BS a lot of 'audiophiles' are proposing. >>>(I have had 100% sucess running S/PDIF up to 18 feet through standard audio-quality patch chords - luck?)<<< >>>How far should I be able to run AES/EBU with the correct 110-Ohm impedance?<<< Vance IP: Logged |
All times are CT (US) | next newest topic | next oldest topic |
  |
|
Contact Us | Symbolic Sound Home
This forum is provided solely for the support and edification of the customers of Symbolic Sound Corporation.
Ultimate Bulletin Board 5.45c