How do we use this repitch node?

[Chazrox]

I cant figure this out, it seems as if its shifting the frequencies up and down but I cant hear a difference. Am I missing something?

[trillbilly]

@Chazrox I was just messing with this as well and thought the same thing. As you move the RepitchFactor knob, you can audibly hear it repitching, but, once you set the knob, the audio seems to be back to normal. I couldn't figure it out.

[Chazrox]

@trillbilly Yeah I gave up lol. Lmk if you figure something out tho! I'll keep trying other stuff too but its looking like I might actually have to take the deep dive into c++!

[dannytaurus]

@Chazrox I asked Claude to describe the Repitch node by looking at the codebase:

Based on the codebase, the Repitch node is a container node in HISE's scriptnode system that resamples the audio signal to process its child nodes at a different sample rate.

What it does:
The Repitch node resamples the audio signal and processes its child nodes with a different sample rate.

It works by:

1. Downsampling the input audio by a specified factor
2. Processing the downsampled audio through its child nodes
3. Upsampling the result back to the original sample rate

Use Cases:
This is useful for processing effects that need to run at different sample rates, similar to how oversampling works but in both directions. It can be used to optimize CPU usage by running certain processing chains at lower sample rates.

Which pretty much aligns with the docs: https://docs.hise.dev/scriptnode/list/container/repitch.html

[Chazrox]

@dannytaurus Thanks. I just think im not setting it up right. I read the docs but im not sure if it requires being inside of a certain chain or if anything helps because as it is just dropping it in and putting stuff in it doesnt really work as far as I can tell.

[dannytaurus]

@Chazrox You probably won't audibly tell if it's doing anything unless you stack a few inside each other with extreme settings.

[trillbilly]

@dannytaurus So what would be the best way to repitch the actual signal in scriptnode? The PitchMod wont work within the effect network, I believe because its mono. Is this correct?

[dannytaurus]

@trillbilly Sorry, I have no idea. I haven't done any pitch-shifting stuff in HISE.

[resonant]

@Chazrox I think it's down/up sampling the contents. Have you tried adding a convolution reverb inside of that node? My guess is that it's changing the pitch of the IR sample in that case

[trillbilly]

@resonant yes, I think this is it. It pitches the contents of the container rather than the incoming signal.

[Chazrox]

@trillbilly @resonant Have you guys ever gotten it to pitch a sound successfully? How did you set your chain up? Im trying to pitch an incoming audio signal.

[ustk]

@Chazrox Ok I have not used it myself, so take what I will say cautiously as I might not really understand what it's been originally made for, so may someone correct me if I'm wrong...
A repitch algorithm is not meant to pitch up/down a signal in a timbre/formant preservation manner like standard pitch shifters.
It's more a samplerate converter that applies the new SR to what's inside and do the opposite at the output.
The use case is more for NN where the model has been trained for a specific SR, or convolution reverb, some distortion, any SR dependent algorithm, etc...
Most non SR dependent algorithm will see no changes.
It's not to be confused with a pitch shifter. I guess a better name would have been "resample"

[resonant]

@ustk Yes, this topic has been discussed here before.

https://forum.hise.audio/topic/13086/change-the-pitch-of-the-ir-sample?_=1765202407224