Topic: wiring an AES digi cable, help?

[JasonSobel]

 

a little while back, there was a great post about how to solder the XLR connections for mic cables, along with a link to an article, giving detailed info.  So I went ahead and made myself a set of right-angle XLR mic cables to run into my V3.  While I was ordering them, I thought to myself, "it would be nice to have a right-angle AES cable, to come out of the V3 as well."  So I ordered a 1 ft long canare 110 ohm digi cable (the DA202, if that matters), and a few extra XLR connectors, so I think I have everything, I just need to know how to wire it up.

There are two wires going up the middle, a white and a red, and then it's shielded.

I assume the shield get's hooked up to pin 1, ground.  and then does it matter which one (the red or white) goes to pin 2 and 3, as long as I'm consistent?  I would think not, but I figured I'd ask here first to see if someone has done it before maybe point something out that isn't so obvious that I might miss if I just go ahead and do it on my own.  any tips?  suggestions?  am I way off base with the wiring?

thanks for any and all help.
Jason

[jjjewett]

AES = 110 Ohm
SPDIF = 75 Ohm

You need a impedence transformer.  Hosa makes one.

http://dv411.com/neutaestran.html

you can get them for cheaper but this is the first link that I found.  Also Ive had success with just wiring an xlr3>rca cable using 75 ohm coax cable.  But when I used a d10ProII, I always used the transformer.

Just make sure you get the 110>75 not the 75>110 one.

John

[Brian Skalinder]

Technically, you should use a 110 > 75 ohm impedance transformer (I think that's what it's called) to run AES > coax.  I've been meaning to do this, but haven't yet - right now I'm just running straight AES 110ohm > coax into my deck.

I checked out the pins on my cable, and they're wired as follows:

XLR 1 (shield) > (no RCA connection!)
XLR 2 (+) > RCA tip
XLR 3 (-) > RCA ring

Not sure if no shield pinout on the RCA is an issue or not.  Doesn't seem to have caused me any problems - I've been using this output for all my recordings lately.  I do, in fact, plan on adding the pulse transformer, just haven't gotten to it yet.

FWIW...

[Brian Skalinder]

So "technically", a right angle cable should be built to get away from the back of the preamp, then > Hosa 110 / 75 ohm transformer, then > rca coax

OK....... got it I think.....

Yeah.  Only all the impedance transformers I've seen are XLR > BNC, so you'd go RA XLR > cable > XLR 110 / 75ohm BNC > BNC / cable / RCA

Or some such.  What a PITA.

[zhianosatch]

sounds like a bitch and a half

[Brian Skalinder]

So "technically", a right angle cable should be built to get away from the back of the preamp, then > Hosa 110 / 75 ohm transformer, then > rca coax

OK....... got it I think.....

Yeah.  Only all the impedance transformers I've seen are XLR > BNC, so you'd go RA XLR > cable > XLR 110 / 75ohm BNC > BNC / cable / RCA

Or some such.  What a PITA.

Brian,

You're running your aes / rca cable into the D100 via 7pin, correct? And you haven't realized any issues of note to date?
I like the sound of that set up!

That's correct, Mike - into my D100, D8 and D7 taboot.  No problems as far as I can tell.

[rabhan]

So I ordered a 1 ft long canare 110 ohm digi cable (the DA202, if that matters)

prob same cable

[rabhan]

i mean, prob same cable type

[Brian Skalinder]

Mine's a Belden 1800F IPR24.  It's 110 ohm, 2 wire, metal-braid shielded.

[rabhan]

Mine's a Belden 1800F IPR24.  It's 110 ohm, 2 wire, metal-braid shielded.

i get nothing from a google search of "Belden 1800F IPR24"

where did you get the cable?

[Brian Skalinder]

I think I got it from the Oade Bros a while back, but am not positive.  I think any 110 ohm 2-wire shielded cable will do.

[Brian Skalinder]

Okay, so...this thread has gotten me motivated and I think I'm finally going to wire up a proper AES(XLR)110-ohm > S/PDIF(RCA/coax)75-ohm cable.

I know the pinout on the female XLR that receives signal from the V3 and the male XLR that feeds the impedance transformer:

Pin 1 - shield
Pin 2 - hot (+)
Pin 3 - ground (-)

And I believe the impedance transformer I want to use is this one, Canare BCJ-XJ-TRB, specifically, the first in the list - XLR female, 110 ohm input > BNC Receptacle, 75 ohm ouput:

http://www.canare.com/digitalaudio/impedancetransformers.html

Here's where I'm not positive.  I think I want the Canare BCP-C4B BNC connector:

http://www.canare.com/bnccrimp.html

For which Canare recommends the following 75 ohm cable, LV-61S:

http://www.canare.com/lv61s.html

And if I'm using the LV-61S 75 ohm cable, it looks like Canare recommends the RCAP-C4A 75 ohm RCA connector:

http://www.canare.com/newrcacrimp/rcacrimpplugcover.html

All of which brings up a couple questions:

[1]  For those with BNC connector experience, does the Canare BCP-C4B look like the right connector for this case?

[2]  I've only ever soldered my connectors - do I really need a special crimping tool for these crimp connectors (BNC and RCA), or will a pair of pliers do the trick?

If all this is correct, the parts list is:

Edited 2003-08-25, 13:30 EST by Brian Skalinder
Looks like the DA-202 cable will be just fine, didn't need the more costly (though more robust) DA-202-2P.

Qty  |  Markertek Part#  |  Description
------------------------------------------------------------------------------
  1  |  NC3FRC-B         |  3-pin XLR female, right angle, gold contacts
     |                   |  Plugs into V3
 10  |  DA-202           |  2-channel digital audio cable, 110 ohm, 10'
     |                   |  Run b/w female XLR f/V3 and male XLR to imp trans
  1  |  NC3MX-B          |  3-pin XLR male, gold contacts
     |                   |  Plugs into impedance transformer
  1  |  BCJ-XJ-TR        |  Canare # BCJ-XJ-TR, impedance transformer
     |                   |  XLR female, 110 ohm > BNC receptacle, 75 ohm
  1  |  BCP-C4           |  Canare # BCP-C4B
     |                   |  BNC connector, 75 ohm
 10  |  LV-61S BE        |  Canare LV-61S, black, 10'
     |                   |  Digital cable, 75 ohm
  1  |  RCAP-C4A         |  75 ohm RCA connector

[Brian Skalinder]

to find what the industry techs use to crimp, that is more affordable, (or go into the cable building business).  Just an FYI and food for thought from a cheap old codger

Thanks, Mike.  I'll poke around and see what I can come up with.

[Nick Culbreth]

brian - let us know how you do w/ the project.  i just ordered parts to make a few s/pdif cables but would be interested to see if the aes/ebu > s/pdif isn't a little more secure since there is only one non-locking connection.

[John R]

guys, i'm not too sure you need an impedance converter(maybe yes for sony's).  i got the presto II's and the only connections are xlr and nice locking rca.  no transformer is evident.  i run the aes 2 into my dap1 and send the aes 1 elsewhere.  never had a problem.  i need to call nutter today on a different matter and will ask him.

jr

[Brian Skalinder]

guys, i'm not too sure you need an impedance converter(maybe yes for sony's).  i got the presto II's and the only connections are xlr and nice locking rca.  no transformer is evident.  i run the aes 2 into my dap1 and send the aes 1 elsewhere.  never had a problem.  i need to call nutter today on a different matter and will ask him.

jr

Yeah, I've been running straight AES/XLR > RCA/coax without an impedance transformer and have encountered zero problems.  But I think I'm gonna do it anyway just for kicks.  Let us know what you find out.