Sync

[fincaman]

Hello All,I am involved in a show where we have had to record the chorus because of the action on the stage,I have recorded the vocals in cubase then output-ed the vocals on their own, in SCS the backing track is Q1 and the vocals are Q2 set to start at the beginning of Q1the idea being that we can alter the ratio of track/vocals at rehearsal, the tracks start together but the vocal track starts to lag behind the backing track to the point where after 3 mins the vocals are 1sec behind the backing in the time elapsed, any suggestions ?

[sound]

Did you follow the instructions given in the Helpfile topic 'Linked Audio Files' ?

[runawaymartin]

Hi fincaman . .
I've had a fair amount of experience in doing what you're after and certainly as 'sound' pointed out the Helpfile topic 'Linked Audio Files' will answer your question.
The most important thing that you must do first is to ensure that your audio file lengths are identical. When you output your files from Cubase make sure that the 'IN/OUT' markers are the same for both/all files, even if this means that there is a fair amount of silence at the beginning or end of any of the tracks.
I'm assuming the reason you are running as two Cues is that you are only using one stereo output from the computer for FOH. If your interface is capable of more than one stereo output I would recommend that you have the vocal track as a sub-cue of Q1 and send it out of another stereo output (add another Device Name) to your mixer. You would then have the ability to alter it's level in the editor (Device Level) at rehearsal and on your mixer during the show (last minute eq/reverb etc could also be done).
Hope this helps and that show goes well . . . .
Cheers . . . Martin

[fincaman]

Thanks to both of you this cured my problem but as I didn't know this when I output-ed my files from Cubase they are of different lengths so I set the "end time" of both to the same time and this did the trick.

Thanks again

Kevin

[fincaman]

Sorry I spoke too soon it worked great on my fairly modern Acer but an older dell (1.7gb 512 Ram xp service pack2)is being used for the show the files link OK but they go out of sync by as much .1 of a second any ideas on curing this on this antique

Kevin

[fincaman]

The Saga goes on,in my post above I stated that on my fairly modern Acer it was fine and it was but I noticed I was using 10.5.1 and there was an update available so I installed 10.6.1 guess what, sync all over the place.My experience of using Cubase with sound card latency problems has taught me that as soon as you get to about 10ms difference you can hear it, the difference in sync I am experiencing is as much as .1 of a second.I have reinstalled 10.5.1 on my Acer and the sync is fine.I would like any comments on this but I am using files of different lengths and setting their end time to the same value
I will try it with files of the same length.Will Report back

[sound]

Kevin,

Permanent Options/Audio Driver: Try to set the Link Sync Point at the bottom to 50ms.

Close and restart SCS after changing options.

Greetings,
Walter

[Mike Daniell]

Also, make sure you have the following option selected:

Permanent Options / Audio Driver: Do NOT use SCS internal mixer

Close and restart SCS after changing this option.

[fincaman]

OK Latest,I have borrowed an AMD Sempron and the sync is fine,as an experiment I reinstalled 10.6.1 on my Acer the sync was again poor (see above) I clicked "do not use scs internal mixer" and restarted this cured it. Could anyone take the time
to explain what is actually happening within the programme ?
In particular I can't understand why on my Acer running 10.5.1 I don't need "do not use scs internal mixer" clicked and with 10.6.1 I do need "do not use scs internal mixer" clicked.As a life long Audio/Electronics engineer it bugs me if I don't know whats going on technically.Please be assured that I think SCS is fantastic,just what you want to do a show.


Regards

Kevin

[Mike Daniell]

Not sure why there would be any difference in syncing between 10.5.1 and 10.6.1 - I'd have to look more into the code. However, here's a bit of an explanation regarding syncing and the internal mixer:

SCS uses the BASS Audio Library for most of the low-level audio processing. One of the optional add-ons for this library is BASSMix, which is what I refer to as the "internal mixer". The internal mixer provides a few useful features, some of which get around some limitations in the core BASS product. But there are also some drawbacks in using the internal mixer which is why in SCS there is an option to not use it.

In the core BASS product there is a function to link multiple audio streams together so that they start and stop together. SCS uses this function for linked cues and sub-cues. So this linking is performed in the audio library itself - a lower level than SCS. However, when using the internal mixer, BASS does not support linking audio streams. That frustrated me no end when I discovered that after spending a lot of time incorporating the mixer! So if you are not using the internal mixer then SCS sets up an array of the files to be 'linked' and then runs through a tight loop starting them as close as possible together. The actual performance of this loop depends on the several factors including the speed of your processor.

[fincaman]

Hello Again, thanks for the explanation Mike and I have good news,when you suggested clicking "don't use internal mixer" I decided to try this on the antique Dell (see above) only to find it was already clicked so I clicked "use internal mixer" guess what sync is now perfect.For interest I decided to try all three computers with and without internal mixer by stopping the playing linked audio cue 5 times and observing the time elapsed :- results

Old Dell, without int mix totally unusable sync miles out.with int mix perfect sync.

Amd, Celeron without int mix OK but a little out 3 out of 5 times stopped.With int mix perfect sync

Acer, without int mix OK but a little out 2 out of 5 times stopped.With int mix perfect sync

My own conclusions for good sync use internal mixer but I suspect on more modern computers sync will be OK on both settings


Thanks All

Kevin

[fincaman]

Last comment (I hope) I reinstalled 10.6.1 on Acer laptop ( 1.8gb core 2 duo, 4gb ram, XP pro fully updated) once again I had sync problems but this time it was better but not perfect with internal mixer off.Reverted to 10.5.1rc3 sync perfect with internal mixer on.

Regards


Kevin