could i have this set up withouth wordclock issues?

[daniel1987]

if i have a 2 8pres connected via ADAT (as converters) to a 2408mk3 , would i have sample clock errors?
is this set up possible?

[XYZ]

The 8 pres should be able to use the ADAT clock to synch, so it will work. but ADAT synch is not as preferable an approach because clock recovery can introduce jitter.

I don't believe the 8pre has an input that would accept a dedicated word clock, so if you have an option [i.e., have not purchased the 88Pre] find an interface with a dedicated clock input, it is a cleaner approach. Then choose a master and hook up some BNC cables and slave them all to your best clock. Better yet, buy a good clock with multiple outputs, and have all 3 units slave to this. I believe Black Lion has a good clean clock for about 500 bucks, and there are plenty of others. Apogee has the big ben that has less than a pS of jitter but is big bucks. Pay attention to terminations.

Anyway, the ADAT synch should work just fine, and if you find the imaging to be good enough, this will work just fine. I'm a bit of a perfectionist when it comes to clocks, so don't take this too seriously.

[Mark S]

The 8 pres should be able to use the ADAT clock to synch, so it will work. but ADAT synch is not as preferable an approach because clock recovery can introduce jitter.

I don't believe the 8pre has an input that would accept a dedicated word clock, so if you have an option [i.e., have not purchased the 88Pre] find an interface with a dedicated clock input, it is a cleaner approach. Then choose a master and hook up some BNC cables and slave them all to your best clock. Better yet, buy a good clock with multiple outputs, and have all 3 units slave to this. I believe Black Lion has a good clean clock for about 500 bucks, and there are plenty of others. Apogee has the big ben that has less than a pS of jitter but is big bucks. Pay attention to terminations.

Anyway, the ADAT synch should work just fine, and if you find the imaging to be good enough, this will work just fine. I'm a bit of a perfectionist when it comes to clocks, so don't take this too seriously.

the 8 pre does not have a word clock in/out but many people link them via adat ONLY since the 1394 connection is so problematic when using multiple units. Just for argument, would the jitter be less in the adat device was slaved to a good word clock?

[XYZ]

You won't get "errors" -- by this I mean it will work, and you will get sound.

ADAT synch uses the bit stream of 1s and 0s to "infer" what the clock is that was used to generate the transmission. ideally, if all the words that were being sent were 010101010101010 or some uniform pattern, the ADAT clock recovery could be made to work fairly well; unfortunately, since we make music, the words being sent have a much less uniform patter to them, so the clock recovery function has to try to infer where the leading edge of that "1" would have been when it was, in fact a zero. Said another way, the specific clock leading edges can cause additional jitter in ADAT synch.

So the next question is, who cares? If all the data gets to the D/A, and it gets clocked out at approximately the right time, out comes glitch free music. Likewise, if the data is recorded, and the A/D samples the data at approximatley the right time, out comes a glitch free recorded track. And there is a lot to be said about this way of thinking. It works, it sounds OK, so maybe we are done. The answer to the who cares question depends on who is asking. If you are only capturing dialog, or doing rough mixes, or demos, etc. This will work extremely well, and reliably. If you are a perfectionist, and you would like super crisp stereo imaging, greater separation of point sources in your stereo mix, etc, then you will want to get to a solution where you have a high quality master clock.

To explain a little of what I'm talking about, when I first heard a low-jitter [i.e., <10ps] system, it sounded like the near-fields were actually headphones, for lack of a better description. You could pin point exactly in the image where things were, and everything was wider and had more left/right space. Depth seems significantly easier to hear also. This was not a subtle experience. I don't have golden ears; far from it, and it was an eye opening experience when it comes to low jitter.

I have an unsubstantiated opinion that stereo sources recorded with low-jitter A/Ds sit in a mix more easily. I'm typically mixing rock and roll and am always working to increase separation using depth, width, volume, frequency, and timing. A stereo track recorded with good A/Ds seems to stay put in the stereo image better. This may be for some different reason, or may be purely suggestive.

OK, so back to your question. ADAT synch will work just fine. If you are a perfectionist, or you are looking for pristine stereo imagining, I think you will ultimately want to go to a single clock source for all your D/As and A/Ds. Also, the clocked system I'm talking about will probably be far more costly than this system, for only a marginal improvement in sound quality.

[Mark S]

does that mean it would be ideal for an interface to have both an adat connection or pipe and a bnc word clock so one could common clock them all?

I'm asking because I've been fighting the multiple firewire woes. So far I've worked this out with help from here but I do not have the confidence I need to take my mobile rig out with 16 channels for live gigs. I'm considering losing the MOTU gear I have for something more reliable (and properly support by the maker).

(896 HD and 8pre here)

[daniel1987]

hey, thanks for all the input and knowledge.

i was curious about something else as well, and that is..

which of these two set ups would sound better or have higher audio quality.
1.) 2 Presonus Digimax D8 connected via adat to a Motu 2408mk3 and all of them synched with a master clock.
or.
2.) 2 Presonus Digimax D8 conected via direct outs into the analog ins of a Motu 24i/o.

i use the presonus as an example but you can replace them buy your favorite 8 ch preamp with atat out, word clock in and direct outs.
the point of the set ups is having 16 ins, i'd prefer the motu 24i/o because of the 24 analog outs. just like XYZ i aim for perfection.


would the sound quality be dratically different or rather equal?

just like XYZ i aim for perfection.


thanks a lot for all your responses!

[XYZ]

OK, so your requirements description helps focus us to a few solutions.

First off, yes, the most pristine approach to ADAT is to use ADAT for the data, BNC for the word clock. But this is IDEAL.

So if we get away from that last 5% of perfection, yes using a single firewire interface with the additional I/O via ADAT will work, not only that it will work great and be very reliable. That is what I do and it is rock solid. my 828mk3 and cuemix integrate the two interfaces [in my case the 828 and the Rosetta 800]. I slave the 828 to the pristine Apogee clock which not only synchronizes the I/O across both interfaces, but also the low-jitter Apogee clock drives everything, giving me a free improvement to the MOTU A/Ds and D/As.

Anyway, I'll assume a few "hard" requirements for your rig:

1] Portable
2] Needs at least 8 mic pre-amps [otherwise, why would you be considering the 8pre? <- if this is not true things would change]
3] Needs 16 channels
4] Using it to record live [Not using it for a live digital mixer <-if this is not true, let me know]


If there is already a 16 ch mixing board [say a mackie 1604], there is a slick trick you can use to steal the signal from it for you I/O, and also take full advantage of it's [nice!] preamps. So let us know about this. I'll assume this is not the case for now, based on your desire for the 8pre.

I agree with you that the MOTU interfaces have a huge bang for the buck, and are very reliable. You would have to spend a hell of a lot more to get a better rig, and I'm not sure there is any company with a driver that works as well and remains rock solid.

So first off, I'll start out with the 896mk3. I'd have said the 828, but you seem to want integrated mic pres, so you probably have minimal line inputs and all mics. 16 mics seems like a lot, but you are probably micing the drums, and that can take 8 right there.

So, assuming you want 8 pre-amps in addition to the 896 I'd suggest these in approx this order lowest cost to higher. If you are not cash strapped, I'd look at 3 and 5, or 4 if you think compression/limiting is a big selling point.

1] Presonus Digimax LT [it won't go to 88 or 96]--Class A preamps, and inserts.
2] M-Audio Octane [again won't go to 88 or96]
3] Presonus DigiMax FS -- class A mic amps, 96k good clock specs, inserts
4] Focusrite OctoPre Platinum -- class A mic pres, compressor and limiter on each channel [not for me, but maybe life saver for live]
5] Mackie Onyx-800R -- Onyx pre-amps

Then you will need two TOSLINK/ADAT optical cables, and a bnc clock cable. If you want to improve your clock, you have a few options, the black lion probably being the best for a portable rig, and is low cost.

1] Black Lion
2] Lucid GENx192
3] Apogee Big Ben

The clock will make both the extra ADAT preamp box and the 896mk3 improve. Jitter is an interesting thing, I don't buy into the distortion reduction [although it will reduce distortion], for me it is more the imaging--stereo sources have a rock solid image, almost like listening to speakers that have "headphone" sound to them. Also mono sources recorded with a good clock seem to "fall into" a mix more easily.

Anyway, I hope this helps!

[Mark S]

Yes, we're talking live 16 channel. Not mixing. I'm trying to do live jazz work so if a quartet by the time you get drums and B3 leslie with two others, and stand-ins I'm at 16 channels. I'm more than a little pissed that MOTU doesn't acknowledge that their firewire units do not reliable work in a daisy chain configuration, nor are they willing to issue older drivers or instructions to make it work: somewhat. I would not have gotten the 8pre it had known that. I can link the via adat but I'm at 12 channels that way. (since I'm using 96k for recording I lose 4 channels on the 896hd which does not have two adat i/o's)

My difficulties with setting things up reliably has me seriously considering a change of gear especially since I'm trying to make money (at some point) with all this: and around here if you screw up once you can pretty well kiss it all goodbye.

I'll look at the options you've noted. I was also looking at some adat to firewire choices available as a stop gap, but I'm still at a 12 channel limit that way because of the 896 hd i/o limitations.

Given the economy I have time to do my homework.

And still, the MOTU gear is so good, I'm still pissed at having made the investment and having to follow this line of thought only because the company support is not there. It's a conundrum.

[XYZ]

Hmm, that's odd. Your setup should work just fine. The 896mk3 should be able to handle 8 channels of 96k ADAT, no problem. I'm guessing you have an older 896 and the older ones did not have 2 ADATs.

Also, Have you thought about trading your 896 with another 8Pre? One 8Pre could be the master, the other the slave. Only gives you 4 outputs, but maybe that's all you need? Might be a slick setup, and still gives you all the flexibility of cuemix.

Other things to try would be a firewire hub.

[Mark S]

Hmm, that's odd. Your setup should work just fine. The 896mk3 should be able to handle 8 channels of 96k ADAT, no problem. I'm guessing you have an older 896 and the older ones did not have 2 ADATs.

Also, Have you thought about trading your 896 with another 8Pre? One 8Pre could be the master, the other the slave. Only gives you 4 outputs, but maybe that's all you need? Might be a slick setup, and still gives you all the flexibility of cuemix.

Other things to try would be a firewire hub.

Yes, I've the pre MKIII, 896HD. It has word clock but only one i/o. That means if I want 8 channels I'm restricted to 48 k at the max.

Yes, I'm considering trading off something, and with the limited adat i/o of the 896 hd it is the logical first choice.

Of course it would be far better that MOTU fix the problem with their units that don't allow multiple firewire devices to work reliably together. For some reason OTHER makers can. This is a well know issue with people trying to link their systems via firewire: daisy chains: they do not sync. There is a work around, which I have done, but it is unofficial and not even acknowledged by MOTU. It requires rolling back the XP firewire driver to sp1 version,and using 3.6.7.x drivers which MOTU will not supply anymore (Hey, I've asked. They said no. Had to find them elsewhere). It doesn't work for everyone. So far it seems to be working okay on my studio system. I have not yet done the change on my mobile rig.

I suppose I'll be able to get it to work but it doesn't leave me feeling secure especially when I head out to do a live club gig. That's not a time to have problems. So, I'm doing some homework in advance. And I'll probably be working toward an all adat hookup with only a final link via a firewire. There are a couple heads that will allow for adat expansion to 32 channels at 96/24. Call it an insurance policy.

And I'd probably head to a Presonus instead of an 8pre (no work clock on it). That way I'm one step closer to getting rid of ALL my MOTU gear. I do not need the headache of a expensive piece of gear that the maker won't support me with.

[XYZ]

Ahh, you are on windows. I was wondering why the multi firewire didn't work for you. This makes more sense now. Seems like the 896 was not intended to take on 8 channels of ADAT @ 96k. If it is a laptop, what about a cardbus FW interface? This will get you two independent FW buses.

For 30 bucks it is worth a try, and if you get a multi-bus card, you can get 2 or 3 independent firewire busses, then you should not get any bus contention.

It is odd that MOTU didn't put a word clock in on the 8Pre. I guess they assume 99% of their users are not going to use an external clock [which is probably true].

[Mark S]

Ahh, you are on windows. I was wondering why the multi firewire didn't work for you. This makes more sense now. Seems like the 896 was not intended to take on 8 channels of ADAT @ 96k. If it is a laptop, what about a cardbus FW interface? This will get you two independent FW buses.

For 30 bucks it is worth a try, and if you get a multi-bus card, you can get 2 or 3 independent firewire busses, then you should not get any bus contention.

It is odd that MOTU didn't put a word clock in on the 8Pre. I guess they assume 99% of their users are not going to use an external clock [which is probably true].

Well, we are in the Hardware and Windows section ;}

And that's a good suggestion to try a card. It's a lot less of a headache than trying to sell gear though I may end up there anyway. Still, some pretty respected daw builder have told me don't even try linking with firewire. It can't be done unless I give up the extra 4 channels and use adat.

Adat is looking much more elegant.

[Mark S]

hey, thanks for all the input and knowledge.

i was curious about something else as well, and that is..

which of these two set ups would sound better or have higher audio quality.
1.) 2 Presonus Digimax D8 connected via adat to a Motu 2408mk3 and all of them synched with a master clock.
or.
2.) 2 Presonus Digimax D8 conected via direct outs into the analog ins of a Motu 24i/o.

i use the presonus as an example but you can replace them buy your favorite 8 ch preamp with atat out, word clock in and direct outs.
the point of the set ups is having 16 ins, i'd prefer the motu 24i/o because of the 24 analog outs. just like XYZ i aim for perfection.


would the sound quality be dratically different or rather equal?

just like XYZ i aim for perfection.


thanks a lot for all your responses!

Hey, sorry to hijack your thread. To answer your question #1 would be the better way to go if you can otherwise you're going through a/d d/a converters twice to get what you want.

[daniel1987]

hahaha sweet

don't worry man i learned a lot reading my ex-thred haha

[XYZ]

Mark S,

I don't think this is what he meant. I think he meant to use the Presonus as a pre-amp only, and then use the inserts to send a line-level signal to the MOTU box, vs using the Presonus A/Ds synched with the same clock [i.e., use the word clock to synch both sets of ADDAs.