AES/EBU input possible?

Dec 30, 2003, 10:50 PM

Hola users,
is it possible to plug an AES/EBU signal to the s/pdif input on front of my livedriveII via an adaptor cable???
I don´t want to destroy any more hardware, so I ask first. Anyone familiar with it ? Thanx in advance

Daywalker

TravelRec. · Dec 31, 2003, 11:06 AM

Hi!

Look here, this may help:
http://www.beis.de/Elektronik/ADDA2496/ADDA2496.html

Greetings!

TravelRec.

mixminus1 · Dec 31, 2003, 08:29 PM

For all practical intents and purposes, AES and S/PDIF are the exact same thing as far as the PCM data is concerned - they differ only in their usage of ancillary data blocks (AES transmits more information about/in addition to the bitstream than S/PDIF does), and the electrical characterstics of the signal on the wire.

I assume you're talking about balanced AES, as opposed to AES on coax (AES-3id)...cause if it's AES on coax, all you need is a BNC-to-RCA adapter. The AES-3id signal level is a bit higher than most S/PDIF signals (0.7-1.0V, as opposed to 0.3-0.5V), but I have yet to come across a S/PDIF input that wasn't perfectly happy accepting an AES-3id signal...and vice-versa.

If it is indeed a balanced AES signal on an XLR connector, you'll need a transformer for that. Several companies make them - Canare, Graham-Patten, Neutrik - and they run about $70. The purpose of the transformer is twofold: 1) Unbalance the signal (and provide proper impedance loading to each signal - 110 ohm balanced and 75 ohm unbalanced) and 2) Pad the level down from the 7V-10V on the balanced side to the standard 0.7-1.0V on the unbalanced side.

If you're trying to do this on the cheap, you might be able to get by with a 10-15 dB XLR pad and just connecting pin 1 (ground) of the XLR to the shield of the S/PDIF RCA input, and pin 2 (balanced hot) of the XLR to the center pin of the RCA. The impedance mismatch getnerally isn't a big deal if you're going straight from one device to another (as opposed to through several patchbays, etc.)...I just tried this with a Graham-Patten A/D converter going into a Roland UA-30 USB audio interface and it worked just fine. I suspect the quality/sensitivity of the S/PDIF input could make a big difference in how well this setup works, but it's definitely worth a shot.

Jan 1, 2004, 10:33 AM

Thanx to both of you an a happy new year!!!!

Your answers got me deeper into business and I am gonna try to build my own solution now.
AES/EBU seems to be the most professional solution besides madi right now and I will try to switch to that connection completely .
All the best for 2004

Greetz Daywalker

P4 2,533@3.06

**dj_stick** · Jan 1, 2004, 10:27 PM

puttin a 75ohm resistor on the coax end and a 110 ohm resistor on the balanced end will help with the impendance difference

Dec 30, 2003, 10:50 PM	#1
Daywalker Guest Posts: n/a	AES/EBU input possible? Hola users, is it possible to plug an AES/EBU signal to the s/pdif input on front of my livedriveII via an adaptor cable??? I don´t want to destroy any more hardware, so I ask first. Anyone familiar with it ? Thanx in advance Daywalker

Dec 31, 2003, 11:06 AM	#2
TravelRec. Alternative Audioproductions Join Date: Sep 2003 Location: Germany / Sachsen-Anhalt Posts: 1,710 Rep Power: 0	Hi! Look here, this may help: http://www.beis.de/Elektronik/ADDA2496/ADDA2496.html Greetings! TravelRec. __________________ Always take a look behind.

Jan 1, 2004, 10:33 AM	#4
Daywalker Guest Posts: n/a	AES/EBU question solved Thanx to both of you an a happy new year!!!! Your answers got me deeper into business and I am gonna try to build my own solution now. AES/EBU seems to be the most professional solution besides madi right now and I will try to switch to that connection completely . All the best for 2004 Greetz Daywalker P4 2,533@3.06

Dec 31, 2003, 08:29 PM	#3
mixminus1 DriverHeaven Newbie Join Date: Dec 2003 Posts: 2 Rep Power: 0	For all practical intents and purposes, AES and S/PDIF are the exact same thing as far as the PCM data is concerned - they differ only in their usage of ancillary data blocks (AES transmits more information about/in addition to the bitstream than S/PDIF does), and the electrical characterstics of the signal on the wire. I assume you're talking about balanced AES, as opposed to AES on coax (AES-3id)...cause if it's AES on coax, all you need is a BNC-to-RCA adapter. The AES-3id signal level is a bit higher than most S/PDIF signals (0.7-1.0V, as opposed to 0.3-0.5V), but I have yet to come across a S/PDIF input that wasn't perfectly happy accepting an AES-3id signal...and vice-versa. If it is indeed a balanced AES signal on an XLR connector, you'll need a transformer for that. Several companies make them - Canare, Graham-Patten, Neutrik - and they run about $70. The purpose of the transformer is twofold: 1) Unbalance the signal (and provide proper impedance loading to each signal - 110 ohm balanced and 75 ohm unbalanced) and 2) Pad the level down from the 7V-10V on the balanced side to the standard 0.7-1.0V on the unbalanced side. If you're trying to do this on the cheap, you might be able to get by with a 10-15 dB XLR pad and just connecting pin 1 (ground) of the XLR to the shield of the S/PDIF RCA input, and pin 2 (balanced hot) of the XLR to the center pin of the RCA. The impedance mismatch getnerally isn't a big deal if you're going straight from one device to another (as opposed to through several patchbays, etc.)...I just tried this with a Graham-Patten A/D converter going into a Roland UA-30 USB audio interface and it worked just fine. I suspect the quality/sensitivity of the S/PDIF input could make a big difference in how well this setup works, but it's definitely worth a shot.