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Tanh and Saturator

+1 vote
Sorry if that question has already been answered, but is there a tanh function or prototype?

Or could the Saturator prototype be used to approximate an hyperbolic tangent function? I tried, but don't really know which sigmoid function the saturator is based on.

Thank you!
asked Jan 28, 2019 in Sound Design by johannes-regnier (Practitioner) (330 points)

1 Answer

+1 vote


What do you need tanh for?

The saturator does have an S curve. You can see what a Sound like Saturator does by putting a full ramp through it and plotting it on an oscilloscope:

The blue line is the Saturator.


Here's the Sound.

There is an ArcTan Sound in the Maths category that also has an S-curve, although it's a different function from tanh.



answered Jan 28, 2019 by alan-jackson (Virtuoso) (15,750 points)
hi Alan,
This is mostly to add a saturation stage in a feedback path. Arctan seems pretty suited, I guess I can simply divide the result by 0.5pi to have it in a good range.
Thank you!
Have a look at the InputOutputCharacterstic Sound. You might find that useful too.
The saturator does have a tanh like shape but it's even better because you can change the shape and adapt it to your needs - I'd go with that
Thank you! Yes, the saturator is great, trying to figure out now the difference between the curve parameter and the order value.
The waveshaper looks pretty fine too actually, with a atan.
Thanks a lot for the answers, put me on the right path.