Change shape of LFO

Posted by: @tripleb

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Did a search, but I did not see this as a request. Being able to change the shape of the LFO controlling the macro knobs. Ideally, an LFO editor, but at least change from sine to triangle, saw, etc. 

I can answer this in three ways:

1. You can achieve most of what you want by changing the shape of the individual response curves. See 1st paragraph below.
2. You can set this up now by using embedded Unify instances. See 2nd paragraph below.
3. I agree. The ability to change the LFO driving function would be useful.

The way macro-knob modulation works in Unify 2 is that each knob is driven by an LFO whose shape is a triangle wave. The result is that if you set the knob value to minimum (all the way to the left) and mod depth to 100%, each parameter link effectively becomes an LFO which sweeps all the way through its waveform (the response curve) forward, then back, and repeats. You can thus achieve most effects just by editing the shape of the response curves.

Using an embedded Unify instance, you can set up a knob in the outer Unify to drive a macro-knob in the embedded instance. Changing the shape of the response curve in the outer instance changes the way the inner knob rotates. An example patch illustrating this is attached (zipped).

As I said above, Unify 2's triangle-wave LFOs are limiting, because they are symmetric. There is no response-curve shape that would effectively turn the triangle into a sawtooth, for example. A simple up-ramp sawtooth LFO waveform would be more powerful (because every parameter-link response curve would then become its own LFO shape), but the triangle wave was chosen because it's more intuitive for common cases. (@Wavesequencer adding a combobox to choose triangle or ramp shapes, plus maybe sine, could address this without much change to the GUI. Or, a "skew" knob to morph smoothly from ramp-down to ramp-up, defaulting to triangle in the middle.)

@getdunne Thank you so much for the detailed response. I can work with this, but there are some cases, as mentioned, that would be hard or impossible to achieve. It's still a great addition though!! And some good suggestions. Thanks.

One for future considerations for sure.

For the moment don't forget that you can save/load curve presets and even copy/paste curves between macro link assignments.

The Macro LFOs are simply phasing between 0 and 1.0 to drive the progress along the drawn curve - if they were to be changed to something else, then the curves you draw would not be doing what you'd expect.. so it could lead to a lot of confusion.

@wavesequencer Agreed that it could make things a bit confusing. Having a choice between triangle as it is now, and maybe a ramp up/down (linear) so that you can create other shapes. And being able to make more complex curves would help. Thanks!!

The macro LFO can act as a up ramp/down ramp (unipolar & forward (start offset on far left) or reverse (start offset on far right)) or as a triangle (unipolar + forward reverse with the modulation set to start on the far left, or bipolar + forward reverse with the modulation start offset set to the middle).

To be able to draw you own LFO curve and have it phase properly from 0 to 1(100%) and wrap back to 0 phase offset you select unipolar/forward with the start offset at the far left - then you could draw any shape you like and it will cycle correctly - eg. attached (the macro knob value rotates from 0 to 1 and jumps back to 0, but the shape on the attached parameter link is then properly cycled).

One thing that can be confusing is we currently only show the output value as a horizontal line moving as it is updated by progress through the phase, but don't show the phase position progress (it would be a vertical line) through the curve - something I'd like to fix in a future version (also a request from Skippy).

@wavesequencer Thanks, I see how it is set up. But what do the 5 curve shape icons do? I press them and nothing changes. I looked in the manual, but no info.

The icons/shapes determine the default initial curve when you add a new parameter link.

Hello!

Would be very interested in a continuously random LFO shape. Would that be a sample & hold? Does s&h traditionally come with smoothing? Anyway, it would be very nice to have something similar to the LFOi M4L device in Ableton Live. You can see the waveform of the LFO, change the type of randomness, adjust jitter, smoothing etc. I am trying to get similar functionality but in Reaper. Ideally, I could do it in Unify2 and be platform agnostic.

I need to investigate the possibility of using xfer LFOTool to route midi CC around Unify2 but fear it could be clunky. A quick "map to last touched parameter option" inside Unify2, like can currently be done (just sans a random modulator) would be ideal. Ableton seems to be unrivalled in this area, except for maybe bitwig. Maybe I just need to ditch Reaper, but I'm so entrenched..

It's a good idea, but will have to wait for some time before we make any changes to Macro LFOs - the last update was a royal pain to debug 😉 - but you could get similar results by having a stepwise curve with lots of different step values (attached example).
If you have two macro LFOs targeting the same parameter, but running and slightly different rates, then you'll get a lot of randomness.. I know it's not as direct as having a dedicated S&H, but this is a workaround.
Otherwise your best bet is to use MIDI plugins within Unify layers that can do this. 

Reaper is pretty great, but others do seem to have better modulator options - even Tracktion Waveform has a nice built in LFO tool for track automation.