AES/EBU Interface

[Phyl]

I've got two computers - one running GigaStudio and the other running Sonar. I'm going to install a AES/EBU capable card in the Giga computer, it will be only used to out AES/EBU to the SONAR computer.

Does there have to be a word clock connection between the two computers?

I've run SPDIF between these two computers before with no problems. I'm wondering if the same would be true for AES/EBU connections, and if a word clock would improve the performance.

 

[Blue Bear Sound]

It would be a very good idea to have both devices clocked by the same source. It assures jitter-free digital I/O, which ultimately means higher-quality audio!

 

[Havoc]

If it works with spdif, it will work with aes. Both are the same protocol, only a different electrical interface. (okay, a slightly different protocol)

 

[Phyl]

That's what RME Hammerfall is saying as well.

SPDIF and AES/EBU are apparently self clocked so the sync information is embedded into the data stream. As far as the data protocol, your right, AES/EBU utilizes 4 bits that SPDIF doesn't.

I'm still thinking that BlueBear has a point though. Using the same clock for the RME and MOTU systems could reduce jitter and improve the audio quality.

Now I have to decide if it's worth $150 to find out how much the improvement is.

 

[Havoc]

In a pure digital system, jitter has no influence at all unless it is more than 1/4 of a clockcycle. It only is important when going from analog to digital or the inverse. That doesn't mean it cannot be interesting to have a central wordclock. It makes clocking much easier. But it won't make a difference to the audio.

Both aes and spdif use the same bit, all 32 of them. It is only the subcode that is different. Or better, that should be different since most gear never looks at the subcode. This subcode is the collection of the channel status bit over 192 subframes so you get a 24byte status block. This info is different, the rest is identical.