Tesselator filter parameters

[henricus1180]

I'm struggling to make sense of HP Filter and LP Filter parameters for Tesselator. The Help text implies they are frequencies, but the values are 0 to 10, rather than Hz. It also sort of implies they may be intensities, with HP Filter dumping more bass and LP Filter dumping more treble as the values approach 10.

 

But with both values set to 0, I find that the output almost disappears by the time it gets to the last step, and it seems to be filtering towards bass (but it is difficult to tell), which would fit with the values corresponding to frequencies in some way. (Is the frequency range determined dynamically by the effect?)

 

With both values set to 10, I find the converse, with the steps tending towards treble, but still almost disappearing with a stable pitch (but not so much when the pitch itself increases to +12 semitones).

 

5 seems to be a more neutral value where the output is audible through all the steps, but there still seems to be some filtering going on.

 

I've tried various combinations of values, but I can't get to a state where I feel I have reverse-engineered the behaviour of these parameters into a specification, so I'm stuck with plain old trial and error when it comes to setting up my Tesselator snapshots.

 

Please could someone put me out of my misery and tell me what the values actually mean, so I can properly predict their behaviour.

 

Thank you.

[reginaldStjohn]

Found a page that describes the parameters.

https://www.fluidsolo.com/patchexchange/view-model/Tesselator,71

[henricus1180]

Thanks, but I've already seen that somewhere else (it's also similar to the wording in the Help text), and it doesn't properly explain what I was seeing (or hearing, rather).

 

However, I think I've worked it out, at least in principle. If the values are treated as if they were frequencies - so 0 equates to a low frequency and 10 to a high one - then the behaviour does actually make sense: In the HP Filter parameter, a zero value will let through most frequencies, whereas in the LP Filter it will attenuate them. Conversely, a 10 in the HP Filter will attenuate most frequencies (they have to be higher than whatever 10 equates to in order to pass through it), whereas in the LP Filter it will allow most frequencies through (pretty much everything is going to be lower than that high value).

 

So in my tests, HP Filter 0 and LP Filter 10 had the least (if any) effect on the output, whereas HP Filter 10 and LP Filter 0 silenced the output even before the last step.

 

This then explains what I described in my original post:

- With both values set to 0, the HP Filter is effectively neutral but the LP Filter is at its most severe, so the output loses more and more treble until there is nothing left.

- With both values set to 10, the situation is reversed, and the LP Filter does nothing, but the HP Filter gradually squeezes out the bass until there is nothing left.

- With both set to 5, both filters are in play, but neither is so extreme as to attenuate everything, and to some extent they cancel each other out.

 

Essentially then, it seems as if the values work in opposite directions for the two parameters, and I guess the simplest way to use them would be to have one set to its 'neutral' value (so 0 for HP Filter and 10 for LP Filter) and the other set to whatever you want to create the sweep you are looking for.

 

It would still be good to get some confirmation of this, and maybe an explanation as to why we have values 0 to 10 rather than actual frequencies in Hz.