AES/EBU mode on CS8412

[tubenut]

Hi

I am not sure how the mode selections work on the CS8412.
I am trying to get a Denon broadcast player to lock on to my Theta DAC.

It will not however.

I have converted one of the Theta Coax inputs to balanced digital and out of the Theta transport I have this locks fine using its blanaced digital out.
However, in comms with Theta I have been told that the codec used on the Data Basic II Transport is not AES/EBU but SPDIF in a balanced configuration….

So, I suspect (if possible) that the Theta DAC has its CS8412 set up for SPDIF mode only. Can it easily be set to AES/EBU?
From rwhat I understand AES is more tolerant of accepting SPDIF codec then visa versa. Can the sub codes be ignored completely? I think I read somewhere it may even improve sonics.

I have implemented the crazymonkeysect PLL mod but I doubt the freq of the Denon could be so far out that the PLL can not lock?

Thanks

[rfbrw]

You need to differentiate between AES/EBU electrical specifications and the AES/EBU flags. The CS8412 does not get setup to accept one type of flag or another. It simply displays the flags sent to it, be they SPDIF flags or AES/EBU flags.
OTOH, the AES/EBU electrical specification differs significantly from the SPDIF one. SPDIF mandates a level of around 500mV pk to pk compared to the AES/EBU level of 5v pk to pk.

[tubenut]

Hi Rfbrw

Electrically I believe I have things sorted with the pulse transformer and changed RC network on that input.

What you are saying then is that AES or SPDIF into a CS8412 is not a problem in terms of codec used, the "music bits" get sent to the filter chip regardless and if the flags are ignored the "music data" is identical?

Hmmm, perhaps there is a quirk on the Denon. Perhaps I need to plug it in to a AES DAC a buddy owns and just verify the output is actually OK.

I also tried a crude quick conversion of just sending pin 2 to coax signal and pin 3 to coax earth but no lock. I know this messes with levels and impedance but it is a temp fix that often does work I have read on some of the home recording forums. Just wanted to see if it locks, not too phased about reflections and jitter for now.

I measured output from the Theta and Denon with a DMM (crude I know) but the hovering readings were quite different between Theta and Denon, the Denon being higher. I believe AES can be anywhere between 2 and 7 Volts. Perhaps Denon is on the High side and overloads my balanced digital input?

Will build a better passive converter to attenuate and try coax that way, if that works, I will re look at my balanced input on the dac.