Topic: ADI-8 DS 96khz broken?

Hello everyone.

I'm very happy working with my ADI-8 DS - however I have a problem running it at 96khz.

The output switches to DS when it senses the 96khz clock and sounds good = all good!
The input doesn't switch by itself but that's fine - I can push the button myself at set it to DS when I want 96khz.

My problem is that the input seems to "fold" or "mirror" the frequencies below 22khz into the frequencies above 22khz.
I recorded a tone from my modular synth gradually rising into around 30khz and then back down. This is the spectrogram of that recording: (the upper part)
http://imgur.com/a/gjB0s
I get the same result all over the first 4 inputs (haven't tried input 5-8)

when I recording the same signal straight into my MOTU Traveler @ 96khz I get the lower part.

I also tried routing the signal into a MOTU Track16 @ 96khz and sending it directly out to the Traveler @ 96khz via ADAT and recorded that. Seemed fine too.

So - is the Double Speed part of my ADI-8 broken? Or is there some technical part that I have missed? (hoping for the latter)

Thanks,
Andreas

2

Re: ADI-8 DS 96khz broken?

The most easy explanation is that when recording the ADAT input signal you missed somehwere in the Motu or its settings or the DAW you used to set this to 96 kHz via ADAT. Sounds like you got only the half sample content.

To check that the ADI-8 works correctly all you need to do is connect its ADAT out to in, then do your Motu test via analog I/O with the DS in the loop.

Regards
Matthias Carstens
RME

Re: ADI-8 DS 96khz broken?

Thanks for answering.

I did this:
analog signal -> ADI-8 analog input
ADAT from ADI-8 out -> ADI-8 in
ADI-8 analog output -> MOTU analog input

No folding! Signal is good!

(doing this actually seems to give me a cleaner signal that plugging straight into the MOTU smile )

So I keep the session open and without changing any settings I unplug the ADAT cable from the ADI-8 input and plug it into the Traveler = signal is folding again.

The MOTU Traveler is fine with receiving ADAT @ 96khz from the MOTU Track16 but it can't handle the ADAT signal from the ADI-8 @ 96khz without folding.

Could there be any difference between manufactures in how the ADAT signal is sent @ 96khz ???

Doing all these test has clearly shown me how superior the ADI-8 is to the Traveler - so I really want to solve this.

4

Re: ADI-8 DS 96khz broken?

That looks like a bug in the Traveller then. ADAT does not include signalling SMUX mode as 'standard', therefore there is no way you can force ADAT to be seen as SMUXed 96 kHz signal other than manually telling the hardware  to work in that sample rate. You should contact Motu support to find out what they have to say.

Regards
Matthias Carstens
RME

Re: ADI-8 DS 96khz broken?

Thanks again.

It's just really weird that the adat signal from the other MOTU interface is read without problems. Perhaps they have the same bug in both interfaces/drives? It's the same company after all...

And on that note I just ordered a Digiface USB to use instead of the Traveler - Hope that'll sort things out smile

I'll report back when it arrives.

Thank you for patience and quick replies

Re: ADI-8 DS 96khz broken?

Oh god... your comment on SMUX not signalling as STANDARD guided my thoughts to RTFM again. And there it was; the MOTU Traveler has a switch that is only visible in 88.2/96khz and only via the tiny hardware menus that sets whether to use SMUX or MOTU(!) signals when in double speed mode. Now everything works perfectly...

Thank you again!