Getting AES/EBU to my computer

  • Thread starter Thread starter joshw
  • Start date Start date
J

joshw

New member
Hey all! I just picked up an Aphex 1100, and it has an AES/EBU digital output. Unfortunately, none of my equipment has it, only S/PDIF. What's the cheapest possible way to output the AES/EBU to my computer? Either a AES/EBU -> S/PDIF converter or a cheap sound card would work for me. Thanks!
 
Probably just a cable might do the trick. It won't hurt to try.

For a diagram: http://www.rme-audio.com/english/download/manuals.htm take the manual of the hammerfall 9652 (9652e.pdf) and go to chapter 8, there is a drawing of a cable for aes->spdif.

This isn't a sure thing since it may be that the subcode is checked, but that would be a rare instance.
 
no, you need to convert the signal:
http://m-audio.com/products/en_us/CO3-main.html

the reason something like the 9652 works is because it accepts both formats. AES/EBU and S/PDIF contain pretty much the same protocol, but differ in the subcode which makes the conversion necessary. not only that but the cable is different for the two formats. While AES is 110 ohm shiedled, S/PDIF is 75ohm coax or fiber. Not only that but the signal level in AES is 3-10V while S/PDIF is about 0.5-1V
 
Not really.

First of all, about 90% of the gear doesn't do a single thing with the subcode. So if you strip the subcode, both are the same.

Second, while the impedances are different, they are not that much different. So for a short cable of a meter or two it doesn't matter. And while the aes is balanced and the spdif not, this isn't a problem either, because at least the aes has a transformer coupling, so you can connect it to an unbalanced input (or the other way round).

Third, while the voltages look a lot different this isn't a problem. The spdif can receive without trouble, and the aes also because it is designed to work with a minimum of 0.2V

Just give the cable a try.
 
Havoc said:
Not really.

First of all, about 90% of the gear doesn't do a single thing with the subcode. So if you strip the subcode, both are the same.

Second, while the impedances are different, they are not that much different. So for a short cable of a meter or two it doesn't matter. And while the aes is balanced and the spdif not, this isn't a problem either, because at least the aes has a transformer coupling, so you can connect it to an unbalanced input (or the other way round).

Third, while the voltages look a lot different this isn't a problem. The spdif can receive without trouble, and the aes also because it is designed to work with a minimum of 0.2V

Just give the cable a try.
Click to expand...

hmmm, i don't know. i see it worked for him but everything i've read has said that it may work for some gear, but not all. And it may not work all the time either. Gear is picky.
http://www.mtsu.edu/~dsmitche/rim420/materials/Interface.html
http://www.answers.com/topic/aes-ebu
http://www.z-sys.com/lit/r-003.PDF#search='Converting%20between%20AES/EBU%20and%20S/PDIF'

and what did you mean by AES needs at least .2V?? It's 3-10V right? According to my research it is.

of course if you're an electrical engineer or something, just tell me to shut up. 'cause I'm just basing this off of what I've read. I haven't done any practical applications on this ;)
 
Josh - If you start out with a S/PDIF or AES/EBU cable, it *should* work just fine (at least *close* to the proper 75-110 ohm impedance). Lynx makes a cable (for around $8) just for this purpose.

With a "plain cable" system like that, you're not going to get a clean digital signal. It'll "sorta" work, but it's not really working right - Clicks, pops, dropouts - They'll come around sooner or later when you least expect it.
 
what did you mean by AES needs at least .2V?? It's 3-10V right? According to my research it is.
Click to expand...

AES uses RS482 signals (RS485 these days, but they are electricaly identical, only a small difference in maximal common mode voltage). This drives the cable with a differential voltage with a top-top of 5V. But the receiver has to be able to work with a differential input of 0.2V top-top. This in order to overcome long cables. Using AES and correct cable (like CAT5 network cable) you can then go up to 1200m without problems. So connecting the output of spdif to an aes input isn't a problem because the voltage is still high enough for an aes receiver to work. But you see that you don't have lots of spare to work with, so keep the cable short.

The inverse works because the voltage on a spdif is limited -not for electrical reasons- but for not sending out too much hash. The spdif receiver has no problem getting 5V input.

Josh - If you start out with a S/PDIF or AES/EBU cable, it *should* work just fine... With a "plain cable" system like that, you're not going to get a clean digital signal.
Click to expand...

Right: it is assumed you use a proper 75Ohm coax (or some cat5 network cable) as your cable.

Josh: when I read your site, you mention you got a rca-rca cable. Was that a proper 75Ohm coax (like used for video) or just an audio lead?
 
Havoc: it was just a standard audio RCA cable. I'm guessing a 750 ohm video would have been better? It's working like a charm right now, but if it gives me any trouble, I'll swap it out for the video cable. Thanks again!
 
You must log in or register to reply here.
Back
Top