AES-EBU Adapter (110-75 Ohm), XLR to BNC

[ubxf]

Hello,
I need to interface some gear that has AES digital connections on BNC to protools XLR (short run 5 feet max) and i was wondering if i should make a straight cable adapter (center pin of bnc to pin 2 of xlr ) or do i need to mind the difference of impedance and insert something (transformer ? ) in between.
Thanks
francois

 

[nielsk]

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=406162&Q=&is=REG&A=details

 

[ubxf]

Thanks, i've seen those but i was wondering if it's really needed for a short run.
Is it a transformer or a couple of resistors inside ?
http://www.neutrik.com/en/accessories/aes/ebu-impedance-transformers/naditbnc-m

 

[canidoit]

I would be happy to know how this is properly done. I have heard you need to do this properly when interfacing AES/EBU and SPDIF otherwise it could damage gear.

 

[Brian Roth]

Thanks, i've seen those but i was wondering if it's really needed for a short run.
Is it a transformer or a couple of resistors inside ?
http://www.neutrik.com/en/accessories/aes/ebu-impedance-transformers/naditbnc-m

Spec sheet sez it's a transformer....

Bri

 

[0dbfs]

I have interfaced XLR-AES, BNC-AES, and RCA-SPDIF many times without a balun or other converter without issue (and without scientific tests!). Just a wire and a ground. Cut an XLR and an RCA... Twist the ends together till it works. I call that discovery. Then make a more permanent connector if you like.

From a tech standpoint AES BNC is not generally spdif. It's typically 2-7V AES @ 75 ohms and is typically used in video systems where facilities already have extensive BNC cabling infrastructure and patchbays and you should use a balun (transformer) to convert to/from XLR-AES. SPDIF is different yet the same datastream so you still get audio.

More info here:
http://www.rane.com/note149.html

Cheers,
jb