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I thought that the Sound Devices recorders might be ideal for use as both a WordClock and timecode master.  These little recorders are not much bigger than a Denecke GR-1 but have the added advantage that they can also generate WordClock and can quickly be removed from the cart for use as a second recorder for over the shoulder shots, or the insert car if you feel that your laptop is too unwieldy.

Unfortunately it turns out that, when using a digital mixer etc, the 7 series recorders cannot be used in this way.  They cannot be used as a MasterClock whilst audio is being fed to them via their digital inputs.  As soon as a 7 series recorder is fed a digital signal it defaults to slave mode and ceases to generate its own clock.  Of course the timecode will still function normally.

I view this as a liability, and I would suggest that anyone who uses one of these machines lobby Sound Devices to add a software switch for the user to manually select whether the 7 series will be the master or a slave with regards to WordClock.  I have spoken with them on this topic and they do agree with my viewpoint.  However, Sound Devices seem to play their cards quite close to their chest with regards to where things are on their priority list or whether they will even implement a given suggestion at all.

Best,

Darren Brisker

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I thought that the Sound Devices recorders might be ideal for use as both a WordClock and timecode master.  These little recorders are not much bigger than a Denecke GR-1 but have the added advantage that they can also generate WordClock and can quickly be removed from the cart for use as a second recorder for over the shoulder shots, or the insert car if you feel that your laptop is too unwieldy.

Unfortunately it turns out that, when using a digital mixer etc, the 7 series recorders cannot be used in this way.  They cannot be used as a MasterClock whilst audio is being fed to them via their digital inputs.  As soon as a 7 series recorder is fed a digital signal it defaults to slave mode and ceases to generate its own clock.  Of course the timecode will still function normally.

I view this as a liability, and I would suggest that anyone who uses one of these machines lobby Sound Devices to add a software switch for the user to manually select whether the 7 series will be the master or a slave with regards to WordClock.  I have spoken with them on this topic and they do agree with my viewpoint.  However, Sound Devices seem to play their cards quite close to their chest with regards to where things are on their priority list or whether they will even implement a given suggestion at all.

Best,

Darren Brisker

Thanks for pointing this out--I was thinking about doing exactly what you mentioned.

Can your digital mixer deal w/ 48.048? 

Philip Perkins

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I am planning on using the 744T as a master TC to feed the Motu Ultralight which in turn outputs to Boom recorder. I am also using the 744T to output a two track  dailies mix to the Motu's SPDIF input. I was hoping to use the AES outs from my Sonosax to generate the dailies mix into the 744T and use the analog outs from the Sonosax directly to the Motu for the splits. Are there clocking issues which I am missing? I spoke with Sound Devices about my plan and they said there are no latency issues but I didn't ask them specifically about word clock. I haven't got my Sonosax back from Switzerland yet to test the AES outs but the rest of the  setup seems to be working fine.  Thanks, Patrick

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I am planning on using the 744T as a master TC to feed the Motu Ultralight which in turn outputs to Boom recorder. I am also using the 744T to output a two track  dailies mix to the Motu's SPDIF input. I was hoping to use the AES outs from my Sonosax to generate the dailies mix into the 744T and use the analog outs from the Sonosax directly to the Motu for the splits. Are there clocking issues which I am missing? I spoke with Sound Devices about my plan and they said there are no latency issues but I didn't ask them specifically about word clock. I haven't got my Sonosax back from Switzerland yet to test the AES outs but the rest of the  setup seems to be working fine.  Thanks, Patrick

I shouldn't expect that there will be any clocking issues with this setup.  You will need your Sonosax to be the clock master.  The 744 will automatically slave to it.  You will need to instruct your MOTU to slave to its SPDIF input.

I'm not certain if Boom Recorder has a monitoring section that allows you to send the return from the computer back to tape returns on your console like Metacorder does.  If there is a method to monitor the return from the computer, put some tone up and listen carefully for 30 secs or so while watching your meters.  Any clocking issues will show up as pops or clicks and also possibly as a slight level instability on your meters.

-Darren

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Hi,

Yip, you can monitor using Boom Recorder, although with some latency. It is indeed a good way to hear if there are clocking issues. But if two clocks are really close together it may take more than 30 seconds to hear clicks, does it not?

I guess you will also need to clock the Sonosax to the 744T, then everything is clocked to the 744T so there should be no clocking issues, I think.

Cheers,

  Take

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Hooked up the 744T, Motu, and Boom Recorder on the MacBook 2 gig. Used the spdif out from the 744T and everything sounded great. 10 tracks with 2 spare on the 744T, no waiting. Burned a DVD on the Mac Book while I recorded 10 tracks of poly files to an external Maxtor one Touch 111 and recorded the dailies mix backup on the 744T. Thanks Take and Darren for the info. I guess I could surf the Net at the same time too! I don't start my next show til the end of Sept., so I will keep testing the system and sending test DVD's to post. BTW, Fox has asked for 24bit 48K DVD-R dailies delivery. Two folders, one with a two track poly consistng of my mono mix and seperate radio's only mix. the other folder would contain a poly 8 track pre fader. Also spoke to a local sound mixer yesterday. He's doing a Pierce Brosnen picture. He was asked by Post to have everyone wired all the time! Pierce declined the obviously OTT idea and told the mixer to have post call him if there was a problem. The mixer was happy...

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I guess you will also need to clock the Sonosax to the 744T, then everything is clocked to the 744T so there should be no clocking issues, I think.

Cheers,

   Take

This is NOT possible.  You cannot use the 744 as a Master sync clock when you are feeding it digital audio.  As soon as the 744 sees a digital input signal it puts itself into slave mode.  As a result, if you try to clock everything from the 744 you effectively have NO master clock at all.  It sounds real ugly.

Best,

Darren

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Hooked up the 744T, Motu, and Boom Recorder on the MacBook 2 gig. Used the spdif out from the 744T and everything sounded great. 10 tracks with 2 spare on the 744T, no waiting. Burned a DVD on the Mac Book while I recorded 10 tracks of poly files to an external Maxtor one Touch 111 and recorded the dailies mix backup on the 744T. Thanks Take and Darren for the info. I guess I could surf the Net at the same time too! I don't start my next show til the end of Sept., so I will keep testing the system and sending test DVD's to post. BTW, Fox has asked for 24bit 48K DVD-R dailies delivery. Two folders, one with a two track poly consistng of my mono mix and seperate radio's only mix. the other folder would contain a poly 8 track pre fader. Also spoke to a local sound mixer yesterday. He's doing a Pierce Brosnen picture. He was asked by Post to have everyone wired all the time! Pierce declined the obviously OTT idea and told the mixer to have post call him if there was a problem. The mixer was happy...

48k, not 48.048?  Since they want a radios-only channel, why not make the other channel boom/plant only? 

Go Pierce.

Doesn't this mean that you have to enter your scene/take Metadata info in two places?  Or will you do paper reports

w/ sound file numbers correlated to scene/take info?

Philip Perkins

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i just spoke with Pierre at Sonosax. They shipped the miniR8 with my Mixer.  (not sure if I will be able to use it on the next show). They ARE planning to do a rev which would allow it to record poly files but there are no plans to give it T.C. out. The internal T.C. system is more a reader than anything, he said. BTW the Sonosax Mixer has Word out along with it's AES outputs but I gather from Darren that  the 744T will no longer work as a T.C. master if I DID try to use the AES in's from the Sonosax. Too bad. I think I will have to buy an external T.C. master generator for all the recorders  and clock it to the AES on the Sonosax.

Boom Recorder has a feature which puts a sound report showing scene and take info in to each folder generated during multi folder recordings. It opens in Safari but I am not sure how it can be used in post. The CSV file (which opens in Excel) is also included in each DVD burn. Regarding 48.048 we are lookiing in to it but there is still some confusion (on my part too) if with a film delivery if  .048 is correct. The show is being cut on a FCP system. Thanks for the great q's and responses. I don't know where I'd be without this site!

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Hello Ramsay,

The sound report in each folder is not yet finished, as you may have noticed it starts fresh when you restart Boom Recorder. I am working on it, to create a sound report from scratch by reading all the audio files that are in the selected folders when Boom Recorder starts, or when new folders are selected.

Opening the sound report in Safari is pretty bogus right now because the template is a little bit too simplistic, this is what I will work on in the future. I will also try to get it to create a .pdf file from the sound report automatically.

The new sound report is an XML file made out of iXML chunks for each recording, then using an XSLT file Safari will be able to render that properly on the screen and to the printer. You can do a lot more with an XML sound report, but that would be too much to explain right now.

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  • 1 month later...

So I was fine using the 01V96 to feed 4 simple tracks of AES/EBU to the 744T. The trouble began when I started trying to sync the different digital devices, lightpipe, firewire, etc.

***No, the trouble really began when you decided to try and clock from the 744.  This is NOT your fault as your line of thought was a correct and you were doing it for all of the right reasons.  This is a design flaw of the 744, but in all fairness to SD, this is a fairly new issue that is now becoming more common as more of us use digital mixers.  The PD4 worked the exact same way.***

What you are saying makes some since although I'd be lying if I said I completely understand why the 744T wants to kick into slave mode with the incoming AES/EBU signal.

*** See above***

I did cruise the word clock thread too, but not until after I got into my own deep muck all alone. OTOH, troubleshooting this web of cables and menus (or trying to rather) has helped me in other ways relating to familiarity of the general interfacing between the components, and writing it all down in my earlier post also helped to gel the specifics in my fading mind. It may not be rocket science, but it is starting to seem like it and I guess it IS computer science when it all goes digital. I only hope I'm a little smarter when this is all done and working...

***NONE of this is as complicated as it currently seems, you are relatively new to this and it will come to you quickly.  Be fair to yourself.  You can't expect to just know all of these things, give yourself a chance to acquire the necessary knowledge.***

My testing of Boomrecorder plays back well. At least it sounds good for the up to 5 minute runs I've been doing. Of course if I have drift involved it could get ugly over time. The disconcerting part is I have no way to check for this.

***At the very least, you should listen for pops and clicks and reduced transparency of the upper and lower frequencies.  If clocking is particularly bad, you will get distortion or momentary (or longer) dropouts.  Record some tones and listen to them.  Pops and clicks that are often very easy to hear with tone can be very difficult to hear with dialog.  This would give you a false sense of security.  I'm not sure about boom recorder, but Metacorder allows you to monitor AFTER the signal has returned from the computer (not the hard drive, the computer), if you always monitor in this fashion, any clocking issues should be immediately apparent. ***

So If I can't master word clock from the 744T due to the AES/EBU inputs, would it be better to master TC alone from it and WC from the MOTU instead? I know there is a MOTU clock/preamp upgrade I can have done, and I plan to look into it one of these days, but I'm hoping to get this all working for the interim without kicking down more $.

***Yes.  I would experiment.  Try using the MOTU as a masterclock first, then if you are not satisfied, use the Yamaha.  You will have success.  I have recently switched to the Metric Halo 2882 as I found it to have better clocking.  BTW, i highly recommend taking an ANALOG feed out of your recorders for the tape returns back to your Yamaha.  Then if you hear any clocking issues you will KNOW that it is on the recording side of things, not on the tape return side.

I do recommend that you TRY the following:  If it works, it will be the best solution for you and will guarantee you sample accurate T/C.

Feed the t/c from the 744 directly into the Motu.  Set your MOTU's clock source to SMPTE; it will then clock itself off of the highly accurate timecode provided by the 744.  Then clock the Yamaha from the MOTU.  The 744 will automatically then clock itself from the Yamaha.  Ensure that you have set the Yamaha's clocking menu to clock from incoming word clock as the Yamaha has LOTS of clocking options.  I am fairly certain that this 'should' work.  However, it 'may' not as it indirectly still relies on the 744.  I do feel that this will work, but if it doesn't, go back to the above mentioned approaches. ***

The main reason I have tried to do it as I have is so i can maximize the use of the Ambient Clock in the 744T. I saw you commented on the same idea in the other word clock thread. I know it's the best clock i've got in the system by far.

***Please lobby with SD on this; I have.***

Boy, this sho is thirsty work. Too bad I drank all the ales while playing with this last night! :P

So what would you suggest as a plan of attack?

***More Ale***

-Darren

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So what would you suggest as a plan of attack?

***More Ale***

Well where do you think I've been while you were kindly typing away to bail me out of the drink? Yep, back from the store and fully restocked. :P

Thanks for changing channels back to the word clock subject. It's a better place for this discussion.

OK. Sounds like a plan. I will try your suggestions. Somehow it makes more since now...although I suspect I spy a false summit on the learning curve, so I'm not thinking I'm out of the woods quite yet.

I appreciate the encouragement also. I'm too am sure it will seem simple some day soon if I keep plugging away and asking myself [and others as yourself] the right questions.

And yes, I will not forget to mention this to the SD team...

Is this 744T slave issue written somewhere or did you discover this on your own?

Thanks again!

EB

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I discovered this on my own.  I don't think that SD had ever really thought about it.  You are very welcome for the help.  Please report back with the results and don't hesitate to ask if you need more assistance.

Best,

Darren

FYI, I just got off the phone with Jon T. and we discussed this 744T clocking issue. He said what he'd like to see in the firmware evolution is user-selectable clock source options. Sounds good to me and would seemingly fix the master/slave bug, but I'm not holding my breath for that update. I'm just a happy camper with mirroring now a reality...although I still haven't tested it on my own box. Saving that for this weekend. As always, SD was very open to the feedback...

Will post an update after I've reconfigured SMPTE and WC routing.

EB

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Thank you for contacting SD about this.  I have been communicating with SD about the need for user selectable clocking options for some time now.  I had hoped to have seen it included in the last couple of software revisions, but unfortunately that has not been the case.  Hopefully, the more users that contact them about this, the sooner it will work its way up their list and become a reality.

-Darren

I haven't logged on to their user forum in quite a while (task loaded), but that might be a good place to post such a request for all to see and sign.

Darren, got your email too. Missed you on Skype last night, but hope you got my reply. I should know how this new routing works by day's end.

EB

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OK, all repatched, still testing, and it seems to be working fine so far (with tone and analog return).

Here's the current setup:

744T SMPTE LTC (Lemo) > MOTU An8 IN > MOTU An8 OUT (for slate jam)

MOTU set for SMPTE word clock (via Firewire SMPTE Console)

MOTU WC OUT (BNC) > 01V96 WC IN (BNC) > 01V96 WC OUT > 744T WC IN (BNC)

The various other connections become moot, except that I no longer recieve a snyc error from the 01V96 ADAT IN, which was a big tip off that I had problems early into this. (A good general test strategy to close all digital loops?)

After playing with all of the possible routing combinations I now wonder if I had inadvertently bypassed the problem earlier by running WC from the 744T into the MOTU first and then into the 01V96. It wouldn't work with the 01V96 being first in the chain for reasons we discussed regarding master/slave conflict with the 744T and simultaneous AES/EBU feed. I now have that one stamped deeply into my cortex!@#$

BUT...by setting the MOTU for SMPTE clock, which I had done earlier (only because I would get 01V96 errors with the MOTU Word Clock In setting, or anything else FTM, for the same reasons), and sending SMPTE LTC to the MOTU from the 744T (either through the 01V96 as earlier or now directly), was the MOTU deriving its WC from the SMPTE input and completely disregarding its WC IN (BNC) altogether? I think so as it would support my earlier routing problems, or lack thereof depending on which was fed to what in what order.

That would mean that even though I originally was patched from the 744T WC OUT, the 744T would still be slaving to the AES/EBU input, which being digital would inherently be tagged with WC so no errors would present...except unless that same WC OUT was fed directly [back] into the 01V96.

I now have the 01V96 feeding the 744T through WC IN, but I suspect it isn't even recognized, again due the the AES/EBU slaving. If it is however (doubtful?) it would at least be coming from the same source feeding the AES/EBU and theoretically be in sync.

After a good night's sleep all this makes more sense...

Irrespective, it seems that your thoughtful suggestions, Darren, do provide for a more robust system all around. And it was a good excercise in patience.

Thanks, man!

On to other issues...like soap and a shower...and more ales! :))

EB

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Hello Eric,

Not to worry you, but isn't there a clock feedback loop now?

774T---ltc-->MOTU---wc-->01V96---wc-->774T

Or is the LTC generated by the 774T independent of its incoming word clock?

An other question, when the SMPTE Console is used to read the LTC from channel 8, can Boom Recorder still read the timecode from the same channel?

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Darren and Take,

Yes, I too figure there is a wc loop...or at least would be if the 744 were reading the WC in, but I don't think it is as Darren mentioned as a possibility. I did pull it as it seems to be just an unnecessary cable, and all still seems to work (sound) fine, but I was curious as to whether the LTC and WC were being generated by the same clock, which I still imagine they are. Since it sounds OK (so far), it leads me to believe that the WC is being ignored altogether.

Another possibility is that the MOTU is reading the LTC and then independently generating a separate and isolated WC based on it. If so, then the WC in to the 744 wouldn't be a loop (I think), but if it's not being read anyway, what's the point? Inquiring minds want to know I suppose. :)

I haven't tried using the 01V96 as master word clock yet, which I think is the other plan of attack, but I will try that also when I have a little more time to dedicate to this. I would suspect the clock is fairly stable, but certainly not TCXO, and I don't have a clue of how it compares to the Ambient. I looked in the manual, but it doesn't indicate, at least not on the spec sheet.

With the number of systems out there, consisting of similar or same components, I find it a bit surprising that these conflicts aren't more publicized and somewhat common knowlege by now.

Oh well, somebody has to be the lab rat. I guess it's my turn. :P

I'll keep playing with it as time allows and will continue to monitor. At some point I should probably record several straight hours of tone to see it there is any drift or sound hash created toward the end. I guess the bottom line is that if it sounds good on playback it is good.

I would like to know for sure however what the heck is happening along the path, out of pure curiosity if nothing else.

Thanks for all the help, guys.

EB

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I am reading with great interest, and I humbly admit with a degree of ignorance on these issues, the whole WORD CLOCK thread. I certainly understand the importance of getting this right and the consequences of getting it wrong, I just have had so little experience in these areas. Virtually all of the work I have been doing involve only ONE digital device, my Deva, and everything else has been analog (the Cooper Mixer, the film camera, etc.). What I would like to see, and I think Eric Burge has already done this, is to post real world setup routines once the dust has settled and there is an understanding of how these clocking issues are resolved. We do have one thing going for us which is there are not too many variables out there in terms of the currently used hardware (Deva, 744T, Fostex, Cantar, MOTU, O1v, Mackie Onyx, etc.) and software (BoomRecorder, Metacorder) that it should be possible to sort it all out.

Regards,  Jeff Wexler

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Hello Eric,

I do know that the MOTU synthesizes a word clock based on the incoming timecode.

If the 744T was generating a LTC based on its word clock input, you would have a loop, as both the MOTU and the 744T would try to compensate.

Personally I would have tried (of course I don't have the equipment, so what do I know):

  744T---ltc--->Boom Recorder

              |--->Slate

  744T---wc--->MOTU

              |--->01V96

Basically the "one clock to rule them all" rule.

This only works correctly if the 744T generates the LTC and the word clock together, I am guessing this is true based on the fact that ambient sells clocks with LTC and word clock output. In this configuration you can use Boom Recorder to check if the sample rate and LTC is generated together.

Cheers,

    Take

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Why is it that the PD4 does not have a word clock? I suppose if it's getting AES in that it would come through that cable, and otherwise It's analog in. I have used mine to feed timecode to the boom recorder by way of the 01V96. Since the M-Lan auto connector gives word clock to the board, I guess that's all that is needed in that setup. I've never had any problems there.

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No, because:

1.  You are right, that would be the preferred clocking procedure if the 744 allowed it.

2.  We all love you.

-Darren

OK, guys. I'm up and back at it. Again, thanks for all your help and support through this. It now is becoming more of a personal investigation into a black hole of different manufacturers' engineering approaches and our personal options to exploit them as end users rather than simply getting this particular system to work. At this point my various sound checks have me convinced that it does work in a variety of configurations, a number of which maintain the same level of accuracy, based on the 744's clock as master.

I called Jon Tatooles again this morning (and I imagine he has had the chance to follow this thread by the time I am posting this). He asserts that the 7 series (and I assume that means all of them and not just the 744T) will lock to the 1st clock source it sees rather than defaulting to slaving from the AES/EBU input as Darren suggested earlier. Even so, it still would be nice to have this as a user selectable menu item. (Listening, Jon?)

Strangely, Take, I tried the scheme you most recently suggested early out of the box (pun intended) and it didn't seem to work. Now it appears to though. This leads me to believe that I must have had at least one of many menu options conflicting with the global scheme.

If I feed both LTC and WC out of the 744T as we've discussed, it seems to work. If I have AES/EBU fed into the 744T its LCD panel indicates that it is locked to a valid external clock source. Hmmm, again a loop? The one thing that I haven't done yet is to call MOTU and ask whether the WC out is direct throughput from WC in or whether it is regenerated independently based on SMPTE input, since that is the only menu choice (CueMix and SMPTE Console) that has ever seemed to work.

Then, as Jon suggested, I plan to dismantle everything and experiment with any 2 given components and the various options. I think that will shed a little more light on this.

And Darren, I must be a glutten for punishment as no I don't think I have an understanding of this quite yet, but it is coming slowly and I am determined. I will give myself an E for effort though. :)

When this is all said and done, and all manufacturers consulted, I think we should form consensus and post it as Jeff suggests. As we all venture deeper into the digital domain, and we must, I think this kind of thing will become more common. Manufactures and models will change over time, but the basic concepts of sync and routing (hard and soft), will be with us for a while for sure. Maybe some day it will all be plug-and-play, but then where would the fun be in that? :)

Also, Jeff, if you're listening: Since you already have a myriad of sub-topics going, why not a new one on configurations and routing? Darren contacted me OL and offered a number of suggestions for configuring the 01V96, and all very good and much appreciated. It would have taken me many hours to derive these options on my own.

Again, we are only getting deeper into this digi world and it is beginning to remind me of the frustration we all have experienced with computers. You call a manufacturer because you have a conflict and they tell you to turn off everything else except their particular product and reboot, which you do, and their app then works fine.

The reality is that we all use a variety of different tools created by different minds and the crux is always to get them to work together in harmony. That knowege is something worth sharing...

Isn't the sound community great where so many people are willing to share their personal knowlege and experience? I can only imagine other industries where the rule is secrecy and deceit. It's this sort of kinship that allows me to march on with confidence and satisfaction with my career choice (and offers perspective on the occasional dick-head producer who thinks, "Just fix it!" is a simple command). :)

Cheers, guys, and thanks again.

EB

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