ADAT inputs

[jarnold63]

Hello all

Ive been messing with this for some time now, I just purchasd the optional ADAT card, it is in Slot 2 my firewire card is in Slot 1. I am running 16 tracks of ADAT from two first gen ADAT machines. the first 8 into the built is ADAT in put the second 8 into the card, no matter what the internal ADAT inputs are distorted, signals are fine no clipping from the machine , when I swap inputs they sound fine , the Slot 2 card sounds fine .. its just the built in ADAT input it is distorted,, ??? changes the clock settings and so forth. but no change. but like I said the Slot 2 card inputs sound fine ??? anyone have any ideas ?? thanks
Jim

 

[cmaffia]

What sample rate is the source? Are you using SRC on the input of one and not the otter?

 

[jarnold63]

the source being the 2 ADATs is 48k, I have them linked together with a BRC , the master is the first and the 2nd is the slave , they are both at the same sample rate , if I flip flop, the outputs in the back of the ADATs , I get the same thing in the internal ADAT inputs, with the other machine and optic cable. So it seems to be something in the internal ADAT input on the Tascam

 

[TascMan]

Have you set your DM's clock to 48khz, slaved off of the ADAT input signal?

 

[jarnold63]

Yes the DM is being slaved off the ADAT signal, heres an odd thing , channel one is always pegged on the DM, no matter what the signal is from the ADAT, it is even pegged or bouncing up to pegged and back down even if the ADAT is not playing , just that channel though , I looked in my routing and everything is setup fine ?? really odd.

 

[AudioWave]

Try a different ADAT cable or swap the ADAT cables see the problem follows. If using the Alesis BRC to control ADAT, take that out of the set up to make sure it is not the culprit.

The bouncing pegged meter observation is almost certainly indicating a clocking issue. If only one channel, that makes me question the ADAT cable. You have both ADAT in & Out connected?

You may also want to attempt a DM mixer SRAM Init from the Diags menu.

 

[TascMan]

Have you checked your bit depth? I am not sure if this would make a difference, but I believe the first gen ADAT was limited to 16bits (or maybe 20 at best). Your DM is typically set to 24bit. I realize that this is resolution, but I would think that there has to be some type of compatibility issue? probably not....not sure.

My other suggestion would be to make your DM be the master and have your ADAT machines slave off of that. Get rid of the WC cable and let everyone slave off of the ADAT signal at 48Khz. I have a MOTU 2408 MKIII that I use with the ADAT input. I keep it slaved to my DM at 88.2 and I notice that if I set it to it's own internal clock signal, I also get the pegged /bouncing on one channel only.

 

[jarnold63]

Audiowave thanks , yes I swapped cables I swapped machines, its still only happens on the ADAT input, I do not have the outputs hooked up at all, I can take off the BRC see if that makes a difference , also Tascman thanks , its odd you have the same issue ??? Ill keep messing with it see if I can get it figured out, whats odd is the optional card works fine , no issues ??

 

[captdan]

Another long shot guess:

This sounds like a classic word clock termination issue. If I recall, when using several ADAT machines, the word clock loop has to be set to 'terminate' at the last machine in the chain. Otherwise, word clock doesn't lock correctly, causing distortion, dropouts, etc etc.

Assuming the sample rate is consistent across all devices chasing to a solid WC master (the DM in this case) everything should work - barring some hardware failure or pilot error.

Caveat: it's been so long since I've spoken ADAT, it could be Greek to me.

CaptDan

 

[AudioWave]

ADAT's don't have dedicated WC like many other digital devices do so there is no termination switch or connector for an termination adapter. ADAT clock comes from an ADAT Sync device such as the BRC or from within the ADAT stream.

Connect both In & Out ADAT cables.

 

[captdan]

I stand corrected. No mystery there. Last time I used an ADAT deck, Abe Lincoln was sitting down in the Ford Theatre to enjoy his last play.

CaptDan

 

[AudioWave]

You might have been of thinking about the ADAT competition, the Tascam DA-88 that did have WC I/O on it.

 

[jarnold63]

I actually use Sonar X2 , producer, ADAT is not something I am looking to use , all I want is to transfer some old material into Sonar, I will try terminating the outputs, see if that helps. never expected this much trouble ?? Oh well Ill keep plugging away and thanks for any and all input. it is greatly appreciated

 

[misterblank]

dusting off the cobwebs from this thread- what was the outcome?