Strange Melodyne sync problem

That's what I ended up doing since I wanted to get this done - basically bouncing the "Melodyned" track down. I just made the other tracks inactive since I sent a message to Celemony support and I'd like to find out what is really wrong. Not a great time to expect a quick reply. But if they come up with something I will report back.

Celemony tech support got back to me yesterday. Pretty good response time over the holiday. Their response was that this sounded like a problem with a tempo change. The song had not been recorded to a click track and I hadn't (purposely) made any tempo changes. But of course, I view the tempo bar and there is a change that I accidentally put in. (Don't you hate it when you push some half-remembered key combination and "nothing" happens. You know you must have done something, but it's not clear what.) I had already "fixed" my problem with the workaround above, but I deleted the tempo changes anyway just in case I worked over the track in the future.



Just in case anyone needs the info later, I'll post his directions for working with tempo changes in Melodyne.



I got this information by Celemony support in January 2011. It's related to Melodyne editor version 1.2.

 

Let me try to explain how the workflow is supposed to be when it comes to handling tempo changes.

Then I hope we can find out whether your problem is caused by any workflow mistake or if it is definitely a bug in Melodyne.

First off, I do admit, that handling variable tempo in Melodyne editor isn't pretty self explaining. It would be much easier, if the DAW passed all tempo related informations (and also all info about meter changes, e. g. going from 4/4 to 2/4 at a certain bar) to its plug-ins. Unfortunately such information exchange is not part of the plug-in-protocols VST, RTAS or AU. Therefore Melodyne editor needs to learn this information during a playback process. In other words: you have to teach Melodyne about the DAW tempo track by playing back your arrangement once.

There are two methods for letting Melodyne learn the tempo- and meter-changes.

A. Upon the very first transfer in a newly inserted Melodyne instance, Melodyne reads the tempo- and meter-information along with the audio. It then knows what's going on in the tempo track of your DAW. But, of course, it only knows what's in the tempo track for the passage that was played back upon the transfer. For example, if you transfer bar 5-9, Melodyne will not know what's happening in the first four bars and it then will assume that the tempo that has been present at the beginning of bar 5 was also happening in the first four bars. This way Melodyne will miss any changes in these first bars - and also in any bars after bar 9. Your next transfer, say from bar 20 to 24, will then be based on a wrong assumption. Even if Melodyne learned the tempo right in bar 20 it would have missed any tempo changes in, say, bar 15. When you then later transfer bar 15, it might learn about this change, but - now having better information at hand - what should it do with the notes found in bar 20? Should it move them? And how could it ever make a right assumption for bar 19?

So - to cut this short - this will definitely lead into trouble, unless your first action after inserting the plugin would have been to transfer from the very beginning of the song (bar 1) until the very end.

Since such a long transfer normally isn't something that you would want to do (at least there doesn't seem to be a musical necessity for this, e. g. on a track that only has a few notes in the, say, 2nd chorus), we offer another option, how to learn the tempo:

B. The recommended workflow on projects that use tempo- and or meter-changes is this:

 

• insert Melodyne on the track – but do not yet transfer any audio material.
• call up the tempo dialog via the chain symbol next to the tempo display in Melodyne and select "Tempo Variation".
• play back the whole song
• click "OK" in the tempo dialog after playback has stopped (as long as you haven't stopped playback, the "OK" button stays grayed out)
• now Melodyne knows all it needs to know about the tempo track, and from now on you can do as many short or long transfers as you like, and you will always have sample accurate sync.

Should you now - after having transferred several parts - decide to change the tempo again, you can do this in your DAW but afterwards you need to call up the tempo dialog again and play back the song once more - again, start at bar 1 and let it roll until the end of the song. Again choose "Tempo Variation" and this time make sure to have turned on "Stretch Audio" in the tempo dialog before you hit playback. (this will move the already existing Blobs, adapting to the new tempo).

I know this sounds complicated but I'm sure you will learn this workflow (method B) easily when you have done it once.

One more thing I have to bother you with:

Another limitation of the plug-in protocols is the fact, that there's no exchange between plug-ins across multiple tracks.

So when you followed the above guidelines for one track and you want to use Melodyne on another track, you must use method B for this second track again (there's no chance that the second track could read what the first track already knows). To avoid this extra effort you might want to consider this little trick:

 

• on the first Melodyne track, learn the tempo as described above (Method B)
• now, before you do your first transfer on this track, save the preset setting of the plugin (name it something like "tempo for song X").
• then start transferring and editing audio on this track
• when you insert Melodyne on a second track, the first thing you do there is to load the preset "tempo for song X" and you will instantly have all tempo information where it belongs and you can start transferring audio right away.

And finally: when learning the tempo in a new Melodyne editor plug-in you may wonder why Melodyne only seems to have captured around 15 bars. This is a known bug. But it is an optical problem only. In fact Melodyne has learned all tempo information throughout the song. It just doesn't scroll far enough. But the moment you hit the transfer button and let your DAW roll from, say, bar 50 onwards, the Melodyne widow will reveal the higher bars.

I hope that this info helps you in finding the right workflow for the future!

Best regards



Nils Hahmann

Celemony support