Big Zebra 2 96khz Bug

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Running at 44.1khz. Patch Zebra to output just a saw wave. Turn the oscillator to crisp. Higher frequencies/harmonics are audibly louder, right? The harmonic roll off from aprox 11khz to 20khz is no longer, and all partials in the saw wave are given pretty much (if not exactly) equal volume.

Now run Zebra at 96khz and do the same thing. Hmm, odd. There is no longer any audible difference between soft and crisp! That's because the harmonic roll off (these are, rather obviously, not actual technical terms :clown: ) that's between arpox 11khz and 20khz when running at 44.1khz, is now much higher in the frequency range (much higher than humans can hear) when running at 96khz. As such the oscillator is running at (in the domain of what people can actually hear) the equivalent of crisp mode at all times when using Zebra at 96khz.

I tested this with FL Studio but I doubt this is related to host. Unless I'm missing something (which I might be), this is a rather serious issue. This makes that function in the oscillators useless and forces all patches that use soft oscillators into the world of crisp oscillators, which, by all accounts, isn't an acceptable difference in sound between 44.1khz and 96khz. If I'm off on something important here, let me know, but this seems like something that very notably needs to be quickly fixed.

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Checked this with Studio One 3. The behavior is definitely related to Zebra and not host.

Skipping through factory presets and it seems like most of them use soft oscillators. This is a really notable issue. There shouldn't be such large harmonic differences between 44.1khz and 96khz. The crisp/soft behavior of the oscillators is clearly unprepared/bugged for/at 96khz.

Given that so many patches use soft instead of crisp, this really needs to be fixed. I urge u-he to avoid going for a lengthy beta or longterm fix here, a prompt hotfix seems (in my opinion) absolutely essential.

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The "soft" version has a roll-off in the highest octave. This was done to minimize aliasing in subsequent modules (filters and such...). At 48kHz this is from 12kHz upwards, at 96kHz this is from 24kHz upwards. "crisp" switches this roll-off off, but may introduce more aliasing in the filters.

Therefore, at 96kHz the difference between "soft" and "crisp" is inaudible when listening to Oscs in isolation, but aliasing levels are still higher with "crisp".

(even though, well, aliasing isn't that much of an issue in Zebra)

Cheers,

- Urs

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In other words, it's a feature, not a bug. :)

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Makes sense (when clarified). In any case I'd make a note to update the manual to provide more info on this point. The current entry about it (which is where my confusion came from) says that it "Affects how brilliant/sharp the oscillator is.". This is technically true no matter the sample rate, but nonetheless kind of inarticulate for people running at 96khz.

It's not a great way to articulate the function (either in how it's setup in the GUI, or its entry in the manual), but I suspect that will be dealt with in some way when we eventually see Zebra 3. :)

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I run Zebra2 @ 96k live as well as Satin, Solaris. Nobody notices but I have IEMs and a pretty awesome stage rig, so it makes me comfy.

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