Adjusting to tempo variation in the DAW

Normally Melodyne Plugin keeps step with your DAW, and the bar rulers and tempo displays of the DAW and Plugin show the same things. If, however, you have a tempo change in your DAW between two sections you have transferred to Melodyne or have altered the overall tempo in your DAW subsequently, you must inform Melodyne of such changes so that synchronicity between the bar rulers of the two applications can be restored. In this tour, you will find out how to do it.

A new constant tempo

Whenever Melodyne registers a tempo change in the DAW, the chain icon near the tempo display will flash orange to indicate that a matter requires your attention. If you do nothing, you resign yourself to a discrepancy between the bar ruler in the DAW and that of Melodyne Plugin.

Click the chain icon to open the tempo window. Here you can inform Melodyne of the nature of the tempo change it has detected, in order to ensure that the two bar rulers remain in step.

If you have simply changed the overall tempo and there are no tempo changes within the song itself, select Constant Tempo. This tells Melodyne that the new tempo registered applies to the entire song and that it should adjust its own bar ruler accordingly.

If you want Melodyne to stretch or compress the audio material to reflect the new tempo, check the box below.

If you select this option, Melodyne will employ time-stretching (or -compression) to adjust the material already transferred to the new tempo. If your DAW employs Elastic Audio and performs time-stretching on its own audio material, Melodyne will behave exactly the same way whenever this box is checked, so the audio material in the DAW and the plug-in will remain in sync.

If your DAW does not employ time-stretching and merely changes the grid beneath the audio material when tempo changes occur, to ensure identical behavior in Melodyne clear the check box in question. Of course, even in this case you may prefer to check the box, in order to achieve through Melodyne what with your DAW you cannot, namely an adjustment  of the audio material to the new tempo by means of time-stretching.

A progressive tempo change

If you have not selected a new constant tempo in your DAW but introduced a progressive change of tempo, select the option Tempo Variation in the Tempo window.

Melodyne is perfectly capable of registering tempo changes and implementing them correctly without any assistance, but it can only do so if they occur within a passage that has been transferred to it. If a variation in tempo occurs between two transferred passages, Melodyne is obviously in the dark. For this reason, prior to the transfer, you should play through to Melodyne all passages containing progressive or sudden changes of tempo so that Melodyne can “learn” about them and ensure that the rulers remain in sync. To do this, proceed as follows; and bear in mind, please, the rules set out in the following section.

While the tempo dialog is open, stop the playback in the DAW and move its playback cursor to a position prior to the variation in tempo. Now, for the benefit of Melodyne, play through the entire passage containing the tempo change (or changes) until a point is reached beyond which no further variations in tempo occur. Stop the playback. In the tempo window, you will see indicated the range of the tempo variation within the passage covered.

Specify once more whether you want the audio material itself or only the grid to be stretched or compressed to reflect the tempo variation.

Exit with OK to apply your settings or Cancel to discard them. The OK button will remain greyed out until you have started your DAW to play the tempo change through to Melodyne and then stopped it again.

Important when working with variable tempo

If Melodyne has not been fully informed of changes in the tempo or time signature, the time rulers of the DAW and Melodyne can get out of sync and transfers will sound at the wrong time or be recorded in the wrong place.

The handling of variable tempo is unfortunately not self-explanatory. It would be far simpler if DAWs transmitted all information about changes in the tempo or type of bar to plug-ins, but, sadly, the plug-in interface at the moment does not provide for this. Melodyne is therefore obliged to learn all the relevant information during the transfer. However, since transfers as a rule do not extend the full length of the song, the tempo window makes it possible for Melodyne to learn about changes in the tempo or time signature during pure playback – in other words, without any transfer being necessary. With respect to tempo learning, if the following rules are observed, everything should go as expected and there is no reason why you should not be able work successfully with variable tempo.

Tip: if you wish to work with multiple instances of Melodyne, here’s a trick that should save you time: once the first instance has learned the tempo, save in that instance a plug-in preset called, for example, “tempo for Song X”. Then open the other instances you plan to use and load this preset into each of them. In that way, all the instances will acquire the requisite tempo information, without needing to go through the same learning process as the first.

* If, prior to changing tempo progressions in your DAW you have already transferred material to Melodyne, then once Melodyne has learned about the changes, before closing the tempo window check the Audio Stretching option. This is the only way of ensuring that the material already transferred can adapt to the new tempo environment.