Use External DAC for monitoring with Carbon?

[EricRobinson]

I really love the Carbon and it sounds fantastic, but the center section is missing a few key features that I REALLY miss in my Crane Song Avocet, like Mono, Phase, and having a separate Dim and Mute (right now I have Dim set to -50 dB, so it is essentially a Mute). I also just like the sound of the Crane Song DAC that I have used for almost 20 years, so hoping I can keep the Avocet in my workflow. Has anyone successfully been able to use an external DAC with Carbon? I've tried doing the requisite setup in Hardware, I/O Setup, etc and not having any luck. Has anyone been able to do this?

[Darryl Ramm]

What are you doing exactly and what does not work as expected?

What inputs are you trying to use on the Avocet? What Outputs on the Carbon? Can you get any signal out of the outputs from the DAW, e.g. just test with signal gen.?

e.g. S/PDIF Optical out on the Carbon to the optical S/PDIF input on the Avocet????

If so all the usual questions apply... do you have the optical outputs on the Carbon set to S/PDIF not ADAT, is everything set to the same sample rate? What is providing the clock? Are all devices connected up to and set to use that clock?

Start at one end and follow the signal. Confirming each thing work as you go. Test with different boxes at each end, DAC/headphone amp, CD player, etc..

[EricRobinson]

@Darryl, thanks for your reply. I actually got it working. The problem was that the digital format converter I was using (M-Audio CO3) wasn't converting TOSlink to S/PDIF, so I switched to an HOSA ODL-312, and that is working. Didn't even have to mess with the clock.

The problem I still have is that the very convenient feature to send both Pro Tools Output and Core Audio output to the Carbon (eliminating the need for input source switching) will only send the Pro Tools output to both Analog and Optical out, and not the Core Audio out. This makes sense as the Optical out is a Pro Tools setting, not a Core Audio setting. I wish there was a way to have “everything that goes to the Main Analog Output 1-2, also go to the Digital Output 1-2” like you could with a 192 converter. Feature request??!!

Perhaps there is a clocking or digital format converter issue going on though, because in comparing the DACs, I actually found the Avocet to sound hazy and the Carbon DAC sounded crystal clear. This was very surprising. Still, it would be great if there was a way to go “mono” and “phase invert” in the master section of the Carbon. Second feature request??!! These are fairly essential features for me.

[Darryl Ramm]

Great you got that sorted out, but I thought the Avocet has optical S/PDIF input? So you could just go optical to optical. Or was there a version that does not have that?

[grmathews]

Hi, I'm struggling with a similar issue. I'm trying to run from the Carbon optical port to a Benchmark DAC1, and the Benchmark is giving a "Non PCM" reading, meaning (according to the Benchmark user manual) "Audio signal cannot be decoded by the DAC1". I've attached a screenshot of the Optical I/O under the Hardware menu. Any ideas how this can be remedied? I know the DAC1 works; i just hooked up a cd player via the optical port and it was fine. Any help would be very much appreciated!

[Darryl Ramm]

Originally Posted by grmathews

Hi, I'm struggling with a similar issue. I'm trying to run from the Carbon optical port to a Benchmark DAC1, and the Benchmark is giving a "Non PCM" reading, meaning (according to the Benchmark user manual) "Audio signal cannot be decoded by the DAC1". I've attached a screenshot of the Optical I/O under the Hardware menu. Any ideas how this can be remedied? I know the DAC1 works; i just hooked up a cd player via the optical port and it was fine. Any help would be very much appreciated!

You have the DAC-1 TOSLINK In connected to what exact port on the Carbon? (it's so easy to goof that up, so check). Using the same TOSLINK cable you used with the CD-Player? If you unplug the TOSLINK cable do you get a different error message on the DAC-1? What sample rate are you trying to run at?

Is that a single Carbon unit or several with/Pre/Pre mode etc. (If so you need to be connected to the main unit).

[grmathews]

Thanks for your response!

You have the DAC-1 TOSLINK In connected to what exact port on the Carbon? ADAT Out 1
(it's so easy to goof that up, so check). Using the same TOSLINK cable you used with the CD-Player?
Yes
If you unplug the TOSLINK cable do you get a different error message on the DAC-1?
Yes, if i unplug the toslink cable the "error" light on the Benchmark lights up (also the "Non PCM" light is still on)
What sample rate are you trying to run at?
48
Is that a single Carbon unit or several with/Pre/Pre mode etc. (If so you need to be connected to the main unit).
Just the single Carbon

Any ideas?

thanks again! -G

[dominicperry]

I had a problem with the RME ADI-2 Pro fs refusing to connect to the S/PDIF output of the Carbon. Avid went away and fixed it with a firmware update.
So you may find if you log a support ticket, they will look into it and see what can be done. It would seem that not all S/PDIF implemenations are the same.....

Dominic

[grmathews]

Yeah I bought an ASC two weeks ago and still don't have the actual code that we allow me to make a call and talk to someone. Seems like they're really trying to funnel everyone into the subscription model, but I'd really rather not pay $700 for a phone call after spending $3k+ on the Carbon. Hopefully someone will help sort it out!

[grmathews]

Finally got ahold of a tech at Avid. She tried a bunch of stuff that didn't work than the did a one minute firmware update and suddenly the Benchmark could read the optical signal. All good!