AnsweredAssumed Answered

AES EBU & SPDIF

Question asked by drugoimir on Apr 20, 2014
Latest reply on Apr 21, 2014 by drugoimir

Hello,

i was just curious if i can just use the spdif I/Os of an ADAU1446 for

direct connection to and from AES/EBU equipment.

For what i've understood, the two formats are quite similiar, with the

exception that AES/EBU contains extra frames for stream labeling,

identification, user data, time stamps and so on.

Saying that i don't need all those extra-features and i want to keep

the component count low, so i will not use a proper

AES/EBU receiver/transmitter chip, what "success rate" can i get

if i use the SPDIF signals directly ? Obviously i'll take care to

be compliant with the electrical specification of the AES/EBU standard.

 

Until now, i've tried some equipment, a CD player and a PC audio card

both equipped with AES/EBU outputs and they are working like a charm.

Moreover, when working on studio equipment i've always mixed and interconnected

AES/EBU on SPDIF and vice-versa using passive adapters, without any side effect.

 

But the question arise because on a studio audio processor manual is

stated that "the digital input signal MUST be an AES/EBU standard signal.

This equipment will not work with S/PDIF signals", or something like.

I've not made a test on this unit, but i got its schematic diagrams and it uses

a popular AES/EBU receiver chip which is able to decode also S/PDIF.

I've found another equipment using the same chip, i connected an S/PDIF

to that unit and voilà: pure music out of the box.

So, this is the reason of my doubts: who engineered the first unit did, with

pedantry, stop everything if the receiver chip reports a non-AES/EBU stream?

I repeat, i cannot make tests on that unit, maybe it works flawlessly

on SPDIF as well.

 

Summarizing: until now i've carelessly, except for electrical matching, interconnected

AES/EBU on SPDIF and vice-versa and i never had problems, never had to say

"oh no! it was not working because i wrongly connected AES EBU to SPDIF", never.

Was it only a matter of luck, or, to avoid using an AES/EBU rtx chip, can i

directly connect the ADAU1446 SPDIF out on AES/EBU inputs on most cases?

 

Thanks

Tom

Outcomes