LFO seems (partly) broken



  • The LFO seems to slow down after about 60Hz, and seems to respond strangely at 40Hz.

    The attached zip contains a HISE project and a Kontakt monolith. Both have a single sine wave sample and a sine LFO with matching phase. Use CC1 to control the intensity of the LFO assigned to pitch (the HISE project has a second mod on the pitch to counteract the pitch shift when the LFO intensity is at zero - don't worry about it).

    I've added a knob to the interface of the HISE project so that you can increase the frequency beyond 40Hz. Compare the difference in sound between the Kontakt version and the HISE version. Below 40Hz they sound pretty much the same, but at 40 and above the HISE version goes funky.

    LFO Test.zip



  • A better way of figuring out what happens with modulation issues is to use a sample with a DC offset at 0dB (so basically everything is 1.0), because then the resulting signal is the modulation signal and you can inspect it in an audio editor instead of having to load two different plugins with another file.

    This being said, I can imagine that the control rate downsampling might introduce aliasing if you push the LFO into the audible range. All modulators in HISE are processed with a slower samplerate (the default is 8x slower) which brings huge performance gains. However if you require a lower setting you can change the preprocessor macro HISE_EVENT_RASTER to any value above 0 (I would recommend either 4, 2, or 1 though as things might get funky with a raster size of 3 🙂

    https://github.com/christophhart/HISE/blob/8ef678ec2fcae0973cc269163404b1f9df967733/hi_tools/Macros.h#L64



  • Thanks for the tip, but I just tried it an it doesn't seem to have solved the issue.

    I'm directly comparing the Kontakt and the HISE patch because I'm trying to recreate an effect from one of my Kontakt libraries in HISE. Both sound the same with the LFO set to 20Hz, at 30Hz they sound different.

    I tried changing the event raster to 1, 2, and 4, but no luck.



  • I made a video showing the comparison:


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