I’m sure you are probably right, I haven’t tried the solution you suggest, but the original point is still valid. Supermassive is not available on all the platforms that Rack supports so this solution is not universal - sure, we can use wrappers to still use these VSTs in other platforms but it is jumping through hoops and doesn’t always work well.
Sure but Clouds makes a really good shimmer and is "universal " so there is that. The only “problem” is that you have to dial it in yourself, and it obviously can be more than a shimmer so you may wonder off… To respond to the original inquiry maybe nobody thought it was necessary because we have pitch shifters, we have reverbs, we have Clouds… And a lot of people like to patch their effects, at least a little bit. I don’t know, I don’t code, but if I did I would definitely focus on things we can’t already do easily and in various ways.
1 Like
Yep, Plateau + Clouds does the job so there isn’t a huge need for it. I used it on my last space ambient patch and thought it sounded just as good as dedicated plugins.
I think one of the things we’re missing (for me personally at least) would be a really good native pitch shifting module. The pitch shift in Clouds doesn’t sound great, particularly on acoustic instruments although it works absolutely fine in a shimmer.
If everyone relies on Host, then developers might stop making new dedicated modules for VCV. I can use the clouds plateau preset though for now. Thanks
1 Like
We have Pitch Shifters:
one by DocB,
one by Squinky Labs,
two by Bidoo,
and one by Surge XT.
None of those work for you?
2 Likes
Two of those are frequency shifters, which are completely different to pitch shifters. The Bidoo and DocB options don’t sound very pleasing to my ears on guitar, although they’re probably fine for other applications. To be fair, I think it’s very difficult to create a natural sounding pitch shifting algorithm in software. Sometimes I use a hardware pedal for harmonising guitar (a TC Electronic Quintessence) which works quite well, it would just be useful to have something like that in a module. I understand that’s possibly not feasible though! 
“To be fair, I think it’s very difficult to create a natural sounding pitch shifting algorithm in software” - that’s what the TC Quintessence is, quintessentially, doing though 
Ah yeah, I meant software that runs on a multi-purpose OS. Pedals are dedicated hardware that run completely different processor architecture and low level code.
Yep, certainly. (It goes both ways, though, as the computers we run plugins/modules today are so exceptionally powerful, and in practice you can dedicate a relatively huge chunk of CPU power to some algo that needs to be a certain way, oversample like crazy if necessary, and so on.)
Anything you can do in a pedal you can do more easily in a VCV module. period.
The problem is more, why would you want to? Who is going to “pay” you for the hundreds/thousands of hours of development?
2 Likes
Shimmer is indeed basically Reverb with a Pitch Shifter in the feedback loop.
Valhalla Shimmer offers multiple configurations.
Valhalla Shimmer: Pitchshifting Reverb Plugin | Shimmer Plugin | Valhalla (valhalladsp.com)
On the origins (and workings) of the Shimmer Reverb effect (Brian Eno/Daniel Lanois/U2).
Eno/Lanois Shimmer Sound: How it is made - Valhalla DSP
Exactly emulating Valhalla DSP Shimmer Reverb would be mostly limited by the characteristics of the Valhalla DSP proprietary Reverb algorithms.
But…in VCV we have several great Reverbs, some with many configuration and modulation options. In VCV we also have Pitch Shifters and the option for Feedback loops. And many other components/tools, if needed.
So, I guess all the (Valhalla) Shimmer Reverb configurations (signal and control paths) could be set up in VCV Rack.
Beside the obvious sampler options…
I am not aware of a VCV Rack module that implements Paul Nasca’s PaulStretch algorithm. It is open source in c++ though, so…if any dev feels challenged…
Paul’s Extreme Sound Stretch (sourceforge.net)
GitHub - paulnasca/paulstretch_cpp: PaulStretch
In VCV we do (of course) have ways to emulate Time stretch algorithms as a patch of seperate components.
But we also have modules that offer some form of (spectral) time stretching. E.g. Tonecarver Blur, which also offers Pitch Shifting (as part of a Shimmer reverb?) and more.
1 Like
PaulStretch: if I could have only 1 plugin that would be the ONE 
1 Like
I‘d love paulstretch in VCV. Hoping someone will create a module out of that lovely algorithm.
Yeah, well, it’s an FFT → iFFT approach. Not simply sample/hold/delay/stutter based (though you can use that approach to emulate timestretch somewhat.
Paul Nasca created several other great tools/synths.
- An overview on his site: Algorithms created by me - Paul Nasca
Paul Nasca has also developed the PADSynth algorithm (e.g. as implemented in his classic ZynAddSubFX soft synth).
PADSynth is another great iFFT (Harmonic Series) based tool to create, well, Pads. In VCV you’ll find great implementations by DocB.
2 Likes
For the layman (me): how would Paulstretch even work in realtime?
Check out Norns Glaciers - not realtime, but runs on samples/four buffers. Live recording was introduced in an update.
There’s PaulXstretch too - a non-realtime stretching VST. https://sonosaurus.com/paulxstretch/
2 Likes
1 Like
Well…to also get a bit into the sample based options for Time stretching…and Time Stretching in general…
Sound could be broadly defined as some Frequency Spectrum, static or developing over time. Any spectrum at any specific moment in time could be a combination of multiple sounds (implicitly also notes/harmonies).
A static spectrum (single ‘note’ for some amount of time) is pretty easy from Time Streching perspective. It could simply be solved by looping the sound.
The problems arise when the spectrum does change over time. The Time Stretching concept is modulating (lengthening) the Time dimension, without modulatiing/effecting the Frequency Spectrum, relative to the time.
Audio sampling is just a way of recording an audio signal and therefore implicitly it’s spectrum. Creating a long row of samples. Each sample representing a fixed timeframe (of 1/samplerate).
So, the (development of the) Spectrum, relative to the time should not change. Only the Time dimension should change. Simply lowering the playback rate of the sample playback is in fact equivalent to lowering the frequency. Implicitly also lowering all frequencies in the spectrum. So, that’s not an option.
What we would like is for each sample or bit of spectrum to last longer then the original timeframe by some factor.
A sample is meant to represent a fixed timeframe of 1/samplerate. So, stretching the whole chain would leave you with gaps between samples.
Ideally you would fill the gaps using some fancy smooth spectral transition, e.g. interpolation using FFT/iFFT.
But you could also fill these gaps towards the next sample with simple copies of the current sample/timeframe. Just the one or maybe also some subsequent samples in a some timeframe. Then just keep playing the same sample or timeframe until a new sample / timeframe is reached in relative time.
This is way simpler to implement then an FFT/iFFT based approach. E.g. by using audiorate sample&hold and delay/echo (with or without per sample buffer reset) or using the read head / buffer of a sampler. This is also the basic principle in a granular synthesis solution.
You just walk over the timeline at some rate relative to the original rate, looping a sample or tiny time timeframe that exists there at that point in time. Maybe smearing things out more evenly using a reverb (basically a complex delay).
Here’s @Omri Cohen demonstrating / explaining some basic sampler / looper based Time Stretching using PatherCap (commercial plugin that also has Time Stretching built in).
2 Likes
You can also create timestretch effects with the free Prince of Perception module. Use a short delay time (<200 msec), switch the freeze on and slowly modulate the scan control to move through the buffer. I made a dodgy tutorial on this, I don’t have Omri’s silky voiceover skills but you get the idea!
7 Likes