Automatic time stretching of imported clips?


Does n-track have a way of automatically time stretching imported clips and loops to match the tempo? If so how do I activate this? Is there a way to make it so that loops remain tempo synced automatically even if the tempo is changed similarly to how loops behave in GarageBand or ableton?

I am running ntrack on an iPhone XS Max if that is relevant

Thank you!

loops and clips imported from the loop browser will automatically match the key and tempo of your song. Same thing is true for all the audio files imported in any other way, provided that they have the necessary metadata.
This behaviour can be changed by tapping on the audio part “key widget” (top-right corner of the part) and selecting/deselecting the options “Follow song musical key” and “Follow song bpm”.
So if it isn’t working for you please make sure that the desired options are activated and that the audio file actually has the necessary metadata (all the audio files in the n-Track loop browser do have them).

As a side note: in the loop browser, by tapping on the small clock icon, you can choose to preview the selected loop following the song key and tempo or in its original form.

Hope that helps!


Thank you so much for this @Piervincenzo !

I’m going a bit crazy trying to find this ‘key widget’ which the manual makes no mention of that I can find… the only options I see on the upper right by holding are ‘flex time’ and things like this…nothing like ‘follow song tempo/key’

Can you please walk me though where to find these on an iPhone?

Also, can you please answer the part of my question about whether the clips remain tempo synced if you change the project BPM after they have already been imported?

Thank you so much!

Oh I see @Piervincenzo

These options are only available with loops that have the metadata stored…

What about it I work with loops from a site like SPLICE?

All my loops have the bpm noted in the file name but I guess not in the metadata as they do not show the key widget in the corner…

Any way to add this manually after importing or something like this? Seems like a major limitation and workflow stumbling block that loops without metadata formatted this way become so much less usable.

Correct. :wink:
Not only loops, but every audio part, to be precise.

They should, but to be honest I’m not 100% sure, depends on the file as said. If you could send us a little sample we can take a look at it for you. You can attach it on an email to mentioning this forum thread or share it however you prefer.

@Piervincenzo that’s a very helpful response, you guys at n-Track have really stepped up your game. How would a layman like me actually add bpm metadata to a given wav file? It would be cool to be able to do. We do have the great Flex Time option that is very useful, and now I see an option for “Reset Speed”, what exactly is that and how is it controlled???

You can edit a .wav file tempo and key info in the wav properties box that appears right clicking on the wav and selecting ‘Properties’ from the popup menu, then scroll to ‘Musical info’. This can currently be done only on Windows & Mac.

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Thank you @Heimie, always happy to help.
I’m not sure I understand your question about the “Reset Speed” option. Basically, what it does is it reset the speed of the selected audio part to its original one after you changed it using “Flex Time”.

Ah, I understand now. Thanks!