Most Moogy Filter?

I know nothing about that, but I was about to say “you should try Alma”. Most people think that is the “moogiest” VCV filter. When I made “Stairway” I was hoping it would be, but I have to admit that cool as it is, Alma is “moogier”.

Yeah, I’ve never had the pleasure to actually play with a Moog synth, but based on videos I’ve heard, Alma does sound the Moogiest.

I had mostly resisted Alma due to the slightly wider width, and the Lateralus sounded nearly as good. But the unwanted occasional Lateralus noise eventually put the nail in the coffin for me.

If there is something wrong with the Vult he will probably fix it. I too am not a fan of modules with giant panels full of mostly empty space. It’s awkward since most modules these days go for a more compact layout.

Hey @modlfo - is this issue real? If so, is it a bug that should be fixed on an intentional thing?

It could be a bug. When there are no jacks connected, I have to insert a bit of noise in the filter so it self oscillates. The inserted noise like 0.01mV (lower that all analog filters) so it should be hard to hear unless is being amplified.

I will check my code and see if there’s a bug.

Are you sticking it through a compressor or leveller? Those things can really accentuate minor noise.

Here is a way overkill patch that demonstrates the Lateralus sin distortion. It is my Subharmonicon emulator with an added switch in the upper right to toggle between Lateralus and Alma. Lateralus sin distortion.vcv (310.0 KB)

I turned the Lateralus drive up to match the level of the Alma. But turning the drive down does not help.

Switch the waveforms to anything other than sin and the two filters become nearly indistinguishable to my ears. But the Lateralus sin waves have an awful distorted buzz.

I think the raw signal may be ever so distorted from a perfect sin, and the Lateralus is accentuating it for some reason. But I’m not really sure.

No compression or limiter. Some simple mixing modules, plus a whole bunch of other extraneous stuff. But I don’t think there is anything there that should be causing problems. I agree there is probably something ever so slightly distorted in the incoming signal, and for some reason the Lateralus is amplifying the distortion horribly. But I haven’t found any other filters that do the same.

What is the sin source? The Fundamental-VCO1 by default is in “analog” mode where there intentionally some distortion harmonics. My “BasicVCO” makes quite pure sines, especially the one called “pure sin” (or something like that).

Yeah, I think that’s pretty common. IIRC Alma does that, too.

Bogaudio LVCO. I experimented with different VCO sources, didn’t seem to make a significant difference. Plus there are other modules in between that could very well be adding their own slight color to the sound.

You can try out my demo patch in my response to modlfo. There is a lot going on that complicates the signal path. But the difference is hardly subtle.

I’m going from memory of tests I ran weeks ago. But it seemed I could force other filters to have a similar effect with enough amplification, but to a much lesser extent. I think I threw on some band pass filters to try to isolate the distorted region. Regardless the origin of the distortion, the Lateralus seems to be hyper sensitive to it, when compared to other filters.

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I’m too lazy to try the patch out, since I don’t have that many modules downloaded. I would suggest next time you are investigating like that that you use the Bgaudio Analyzer XL to see what’s going on. It’s a great module. Also, try one of my filters - I doubt that they make funny noises.

I did try the Analyzer XL, and couldn’t see the distortion, though I could definitely hear it. But just now I amplified the signal to bring the noise floor up where it was visible, and I could then finally see the noise in the Lateralus output. If I really push the Alma overdrive hard, then the noise becomes audible (and visible) as well. But the Lateralus amplifies that low level noise to audible levels even at very low drive settings.

I am using one of your filters a lot recently! I think I have discovered a new use case for this filter that people may get excited over. If I can just get over my fear of recording a demo with voiceover, then I will post a patch and pseudo tutorial video demonstrating the technique. If it takes much longer, then I’ll simply post a patch and video with a written explanation instead. Written discription only just doesn’t have the same impact.

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Here is an ultra simple patch that demonstrates the issue - vanilla VCV plus count modulo for a switch, and the Lateralus and Alma LPFs. Also Glue for some labels, but that is totally unnecessary. simpleLateralusSinDistortion.vcv (6.8 KB) (@Squinky too)

With the switch off, adjust the mix output and/or adjust the lateralus drive and hear the change in character of the Lateralus noise/distortion. Counterintuitively, some of the worst distortion occurs at low input and/or drive levels.

Turn the switch on, and Alma remains clean sounding as Mix volume is swept as long as overdrive is kept to reasonable levels.

I have found the bug. It was just the tolerance of one of my solvers. I will publish a fix with my next releasez

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Nice!

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:+1: Glad you found it.

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I see a new vult update on the library. Can we assume this fix is included? Thanks so much.

Yes. Version 1.17 includes the fix.

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Actually v1.17 did not fix the problem for me :thinking: , but v1.18 did :smiley: .

Thanks for posting the fix.

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But as reported by rydh.nils, Lateralus no longer self oscillates. It now takes the briefest of gentle nudges (any input) to initiate self oscillation. :frowning: Once self oscillation is initiated, the input can be removed.