Here’s a way to “measure” that. here I took two LFOs, set them both to .01 hz, then ran them through DC blockers set at 50hz. You can see both on the scope and the specturm analyzer that the VCV LFO is smooth, but the bogaudio has jaggies. You might try logging a bug with bogaudio - they have been pretty good in the past with fixing things. And, that’s what this is, a bug.
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Ha! I noticed that inadvertently with the stepping on Bogaudio. I was using 8FO to modulate a few different things in an effects patch, and got a really crazy sound with Glitch FX’s Satanaut. I couldn’t work out how it was making that sound, then I realised it was a stepped output from 8FO in slow mode. I actually really like it for some effects, it was like a really slow arpeggio.
However, wouldn’t a simple slew limiter fix this if you want a smooth output? Or am I missing something?
Yes, simple slew limiter would fix it. Which is very close the the one pole low pass filter I mentioned. But in any case it’s it bug. Like many bugs, it can be worked around. If you actually wanted that stepped sound that would be an unusual case - then you’d probably step it yourself with a S/H?
I tested a few different LFO’s and it’s only the Bogaudio LFO’s that has harmonics on the sine output, and this surprised me. Then I looked in the right-click menu of the LLFO, and there you have two settings for “Output sampling” and “Smoothening” for deliberately changing the waveshape, to be more jagged or more smooth. I think what happened here is, that all his LFO’s has that circuit, and it’s in the signal path all the time, having the side effect of producing noise at the neutral setting where it should be clean. I’d imagine he just forgot a (IF) check in the code for the neutral case where this circuit should be decoupled.
I see jaggies only at 0.1Hz in slow mode else the 8FO behaves fine. The LFO/LLFO have smoothing settings so cranking those up gets rid of the jaggies.
At the default 2HZ/120BPM:
Exactly the same as LFO and LLFO. Compare that with VCV LFO, or any of the others:
ok, at 0.1Hz in slow mode and in 2Hz normal mode, BPM doesn’t seem to matter, I see it at 75bpm as well. Time to file a bug rather than waffle about it further here 
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I never use the 8FO, I use the LLFO and the LLFO and the regular lfo. I thought I noticed this in all of them. Might be wrong.
those two both have smoothing setting in right-click menu
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Ah, gotcha. Read these posts too early haha
I created a thread a couple weeks ago about stuttering happening with my LFOs, particularly the super slow LFO from frozen wasteland. I was modulating the super slow LFO with a bog audio LFO but then to try and troubleshoot why the stuttering was happening, I remember removing the bog audio LFO from the patch and the super slow LFO was the only other one left and it was still stuttering. Could something like this be happening because of a bog audio LFO even after you remove it from a patch?
if you can repro this with just the FW super slow LFO and please file a bug on his github please. Any module removed from patch will never ever make sound after that, or process anything.
oh - I never notice the smoothing control. I guess in the normal mode the sin output is smooth anyway, so it’s fine that it defaults to off. But in the slow mode it should be on. At least for the “smooth” outputs. I think the problem here is that this LFO has too many options. Too many for me, anyway!
8FO is mine…thanks for noticing this, will fix.
For the record, 8FO does have a smoothing control – it’s the knob marked SMTH (panel space is always a thing). Internally it’s a slew limiter, same as in my other LFOs.
For you DSP guys, the cause here is: all my sine oscillators, LF or otherwise, use a wavetable. I did without interpolation, back in the day, to save CPU, thinking if the table is big enough (here, 4096 samples) it’d be fine. At audio rates, there are some extra harmonics, but I find those generally pleasing, as in FM-OP. But yep, doesn’t work well for LFOs. Enabling interpolation fixes it.
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To unclear here. Do you have an optional slew limiter, or an optional interpolating lookup table?
Wow cool. Great to know. Just for clarification for me, does your regular lfo module, not the slim one, have this steppy issue? That’s the one I was using when I had the stutter issue, not the 8fo, and not the quadrature one. I must admit my memory is a bit hazy, as after I experienced the issue I tried other LFOs, including your quadrature one, and now I can’t quite remember which one was giving me the issue, but I think it was the plain regular lfo…
Yes, like I said above:
looking forward to the new version! i dont want to switch to another LFO! love yours for my work (using it for museum light installations)
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Yep. I use tables a lot. But mine (for historic reasons) all have first order interpolators in them. Each table entry has a value and a slope, not just a value. That’s what I used for my sine LFOs. And of course I have unit tests for the accuracy.