It was caused by having different sample rates in 2 different samplers. I had to convert all to 41.1khz which is what I started my project at.

@David-Healey (C3)_F_140BPM_RTM1 [2026-05-04 102107].wav

@David-Healey

wav file is 75600 samples (140BPM) confirmed in Audacity, HISE sample editor showing 82286 as SampleEnd. Is HISE adding padding on import? or maybe a bug?

EDIT:
Thinking this is the issue as to why I am hearing smearing even at 100% stretch. I set the SourceBPM to 140 and engine host to 140 and I still hear smearing like its slowing down 1BPM or so too with Timesync Mode activated.

@David-Healey What unit is SampleStart/SampleEnd displayed in inside the sample editor? Is it raw samples, or something else?

@David-Healey thanks!
Okay so num quarters is out of the picture now.

My question is how does HISE know what the BPM of the sample inside the sampler is? I know how to set the internal BPM for testing:

Engine.setHostBpm(120.0);

But do I need to tell HISE what the actual .wav BPM is, and if so where is that set?

Also, are there any settings to optimize to reduce artifacts? Even at a 5 BPM difference it sounds really smeared, and my recordings are high quality. I know HISE uses Signalsmith for timestretching, and on their demo it sounds clean compared to what I'm getting in HISE so I'm thinking it's a settings issue on my end.

Hey, I'm building a guitar rhythm loop based plugin and I cannot seem to get the timestretching to sound good. Even with 1-2% stretch it sounds smeared and in some cases at 0% it still sounds smeared with TempoSynced mode activated.

I tried setting NumQuarters (16 for a 4 bar loop at 140 BPM) and SourceBPM via getTimestretchOptions/setTimestretchOptions and it doesn't seem to make any audible difference.

My setup:

HISE 4.1.0 (commit a29ff452)
4 bar loop at 140 BPM, 4 bars
TempoSynced mode
NumQuarters = 16, SourceBPM = 140
Tested at both 44.1k and 48k sample rates — same artifacts at both

Here is my current script:
javascriptonInit
{
const var Sampler1 = Synth.getSampler("RTM_1_140");
const var obj = Sampler1.getTimestretchOptions();
obj.SourceBPM = 140;
obj.NumQuarters = 16;
Sampler1.setTimestretchOptions(obj);
}

A few specific questions:

Is the smearing at 0% stretch a known issue or am I doing something wrong in my setup?

Are there any TimestretchOptions properties beyond what's documented that might help for rhythmic/percussive material like guitar chugs and rhythm loops?

Is there a recommended approach for loop players specifically, or is the sampler module not the right tool for this use case?

Has anyone successfully integrated Elastique or Rubber Band v3 into HISE and is there any existing code or PR for this?

I really just need clean stretch of about 10 BPM up and down from the source tempo. Any help appreciated, thanks!

This fixed it Dave thanks!

Hey everyone,

I exported a chorus pedal from the Max RNBO guitar collection, but every time I get to the “Compile DSP Networks as DLL” step during migration, HISE crashes.

I’ve followed the steps from videos and forum posts as closely as I can, but I still can’t get past this crash. I’ve also tried using older versions of both Max and RNBO, but the issue still happens.

Has anyone run into this before or know what might be causing it?

Im on SONOMA 14.6.1 / HISE 4.1/ MAX 9.0 / RNBO 1.4

Any help would be really appreciated.

Thanks!