LFO timestretching position issue

I have been attempting to implement the method of timestretching where a sawtooth lfo is used to scan the granular positions. I understand how to set this up, pretty easy… I don’t completely understand some of the resulting behaviour though.

I am finding that the playback will start at position 50 and there will be a brief sound from position 50 before the lfo switches the position to 0 and begins to scan through the grains.

This seems to happen every time the sample is retriggered, but does not seem to happen if the lfo is left to loop through.

It does not seem to matter which sample I am using or what lengths I have taken to neatly trim the sample to a length that relates to the BPM of the track.

Is this a normal shortcoming of using this timestretching method? Or am I doing something wrong? Or is it a bug?

I have watched all the available tutorials etc I am aware of and I believe I have set everything up correctly.


Did you have the amount on the logo page set to 50? (default) . If yes, try to play with that parameters. With the “granural stretching” not always things went as you expected :slight_smile: Hope it helps


Yes I have the amount on the lfo page set to 50 and the position on the sample playback menu is right in the middle. These are both specified in the videos polyend issued on YouTube and seem simple to understand… :thinking: So I think it is not the settings that are the issue.

To clarify things further: when you look at the red line representing which part of the sample is playing (on the sample playback screen), I can see that the sample briefly plays from the middle position before the lfo kicks in and the red line skips to the sample start. This is the bit I do not understand… On the face of things it looks like a delay between the sample playback starting and the lfo triggering, however, I could be wrong.

In any case it creates a glitch every time the sample is triggered, which is annoying.


I’ll investigate on the next few days :slight_smile:


Ok…yes, I think this can be a bug.

It sounds like the LFO had a slighted shifted phase at the beginning, kind of a delayed reset…same on your side if I understood correctly, right?

A little workaround is to slightly lower the attack on the amp envelope page, with the right amount it kinda works.

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Hi _noir,

Yes, I think you have understood perfectly, thank you for taking the time to read this and for investigating :slightly_smiling_face:

Also note, I have observed a similar behaviour using an envelope as well (although that is difficult to describe in text, I’d have to video it to provide more detail).

I tried your trick with the volume envelope and it does slightly mitigate the effect of the delayed reset. It’s not perfect but I will roll with that option for now :+1:t2:

I will leave it with the polyend team to see if this behaviour can be replicated consistently and to see if there is a fix. I appreciate there is a 1.7 update coming up and that might take priority over this for the time being.

It would be super if this quirk could get straightened out eventually as the lfo timestretch is such a cool feature of the tracker and it is so close to being perfect :ok_hand:

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Yes it’s also on the envelope…by the way, hope this will be fixed soon! Have a nice day dude!:metal:

Thanks, and you my friend :raised_hands:

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