Quality of timestretch

Yes, that’s hard to avoid. When you are raising the pitch or speeding up the tempo, you are feeding the stretcher more and more samples that it needs to crunch on. It needs to process a lot of input for a relatively small amount of output.

This could only be optimized by ignoring/skipping parts of the inputs, but this is tricky to realize - cause you then somehow need to decide what to ignore and what not to retain the original character of the sound.

That said, this also is a bit out of my control. We are only using the library. The author and thus the only one who could change or improve that is Chris from breakfastquay

I could collect issues and wishes though and send them over in a compact and moderated form.

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thats fair taktik, thanks for your reply. maybe a low quality cpu setting in the future could be nice because now its almost unusable in a session with medium taxed cpu from other stuff

I agree , rubberband does a fantastic job , and don’t forget we have the realtim effects commands to mangle it even further .

Ye rubberband is not perfect, but it does ok I think. Simple material is just fine…complex material like whole mixes or stuff with reverb will degrade.

Why no formants preserve option? Rubberband can do this?

Also I get tiny clicks…for example orchestral hit sample with tail…is very tempting to use the pitchshifter to preserve a single length along the keyboard…sample itself is clean…then when reducing length with timestretch and playing on the keyboard, I get little clicks between the notes, also when rendering offline or realtime. Like the pitchshifter would need some extra samples to run on when cutting out sound, and a fadeout/smoothing somewhere…

I mean it is clicks that keep me from using it in this usecase, I would not want them in my music!

Best if we could have length/timing in pattern command or have automation on them. This would make some kind of granular synthesys with not so much effort i guess .

Assign lfo , envelopes and the result will be fantastic


Have you played with adjusting the Line setting? Before activating the pitch shift, check the beat length in the waveform editor and multiply the total beat length by your LPB setting and use that as the line setting for the beat-sync pitch shift. I tried this with several Orch Hits I have and only got clicks and stuff at low settings for the beat-sync. Once I det it based on the original sample beat length, the clicks disappear. Though, you might have to revisit this if you change your Tempo and/or LPB settings later on.

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Actually you could precalc the stretched samples so that they wouldn’t need to stretched in realtime. This could be done in advance by pre-analyzing pattern data or storing stretched sample to memory when played for first time.

This would reduce CPU usage a lot with expense of RAM usage. RAM is cheap.

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In theory yes, but in practice this gets super complicated thanks to Renoise’s ability to manipulate sample playback in so many ways (via pattern effects, modulation, macros and so on).

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