A final word to digital output/clock

Woland

Inspired
Hi,
I play live with my axefx into a motu 828mkIII and ableton live.
In order to make more room in the audio card for other instruments, I would like to use the spdf connection and free two analog xrls.
Now, the only problem is that it seems the axefx could only be slave, which is not possible for our setup (all the show will be slave to my unit!!), but some members think otherwise:

" The AxeFx II will slave to clock on S/PDIF input but it needs to be at 48khz. "

So, where is the truth? Can I just plug the two spdf cable from motu to axefx (and viceversa), and the axe will clock to the motu automatically, or there is something else I need to do first?

Thank you!
 
I don't know about the Motu, but I connect mine to a profire 610 through one spdif cable (out > in) and through the profire menu in Windows I can set it to be master or slave. The AxeFx only operates at 48khz. Does the Motu has a Windows or Mac software for setup? You may be able to setup it there.
 
Yes, if in the motu software I select the clock to internal it became master, but it seems the axefx it will not sync, as I hear the tipicals "clicks" that happen in those cases...
 
It's slave for S/PDIF INPUT, but the clock input must be 48KHz.

It's a master for S/PDIF OUTPUT. The clock used will always be 48KHz.
 
I have the same setup with the 828mkii and in the Motu software just select spdif as your clock source at 48khz. In the Axe FX I/O menu make sure spdif is active and change your spdif source.
 
I use SPDIF to Presonus Firestudio to monitors so maybe this may help you.

I use the front instrument jack and the AXE is set to analog not SPDIF. Then on the Firestudio config I set the AXE FX as master 48khz. In this setup, I have no sync issues and am able to use the inputs on the Firestudio for Bass, Mics with no issues. I also must use the Firestudio ASIO drivers in my DAW, not the AXE drivers. Changing the AXE i/o from analog to SPDIF is only applicable if the input is coming from the SPDIF which I assume is not the case for you.
 
Same with my Focusrite Scarlett 18i20. The AxeFx spidf goes into the 18i20's spdif in, where I have to set the source clock to "spidf". The AxeFx is Master, no clicks, no pops, just fine.
 
Thanks to all.
Yeah, that's confirm my thoughts. Basically, if I want to play live using the spdf out, the axefx must be master... And this seems quite stupid, IMO. But it is what it is. I hope this problem will get addressed on the AxeFxIII !
 
Thanks to all.
Yeah, that's confirm my thoughts. Basically, if I want to play live using the spdf out, the axefx must be master... And this seems quite stupid, IMO. But it is what it is. I hope this problem will get addressed on the AxeFxIII !
That's not an AxeFXII issue; it's how digital audio works. The source is always the master because the destination has to sync to it as a reference. The only way around it is to have a word clock input (which I have whined about wanting since the Ultra) or to go through a device such as the Mutec MC4 or MC6 to lock the two units. I actually used an MC4 with my 828MKIII before I sold it and using the TOSLINK worked fantastic. The Mutec was the best thing I could find because it was bidirectional (I was using this for re-amping) and it works exactly as advertised.

The other option is what I actually did which was sell the MC4 and MOTU and buy a soundcard that has SRC's and can resync the signal on each input. I bought a Digigram VX882HR and a BOB8 for it. It's an internal card though and it's not cheap....but it's got 4 stereo AES/IO and I don't have to care about sample rates and word clocks anymore.

But my point is that it's not the AxeFXII's fault that digital audio works like that. The pops and clicks aren't coming from it; they are coming from the MOTU.
 
It's slave for S/PDIF INPUT, but the clock input must be 48KHz.

It's a master for S/PDIF OUTPUT. The clock used will always be 48KHz.
If this is true, then you should be able to have the Axe-FX as a slave. Simply plug in the s/pdif output on your master device into the s/pdif (or AES) input on the Axe-FX. The question is whether or not the Axe-FX will lock to that incoming clock if the Audio Input is not set to SPDIF/AES. If not, then that would be a good firmware update to allow sync to incoming clock via SPDIF/AES without having to use that digital connection as an audio input.
 
If this is true, then you should be able to have the Axe-FX as a slave. Simply plug in the s/pdif output on your master device into the s/pdif (or AES) input on the Axe-FX. The question is whether or not the Axe-FX will lock to that incoming clock if the Audio Input is not set to SPDIF/AES. If not, then that would be a good firmware update to allow sync to incoming clock via SPDIF/AES without having to use that digital connection as an audio input.

Right it only works with Audio Input set to S/PDIF. The clock for the outputs is hardwired so no firmware update will allow that to happen.
 
The output is a non-issue, but possibly a firmware update could separate the clock source from the Audio Input source.
 
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