New filters

[Toltekradiation]

hi,
I finally dared to dig the preenfm code, and, it was worth it 
here is a firmware attached, that include some more filters :
- lp2 : lp with double filtering
- same for hp2 and bp2
- tilt : adaptation of this : https://www.musicdsp.org/en/latest/Filters/267-simple-tilt-equalizer.html
- allpass : simple allpass filter, need some more work, not sure what to do with this one...
- saturation : this : https://www.musicdsp.org/en/latest/Effects/42-soft-saturation.html
- sigmoid : a classic tanh distortion : https://www.musicdsp.org/en/latest/Other/178-reasonably-accurate-fastish-tanh-approximation.html

I hope you like it!

your ideas and bug report are welcome.

If you want to see the code, here it is : https://github.com/pvig/preenfm2

(edit 2019-09-11 12:45:37 PM : updated attachement)

[kyoto]

wow - great - now will try

[matrix12x]

Awesome!!! I've been wanting to do an all-pass for a while. I also wanted to do a comb-filter with some distortion. I will try this out and let you know if I find any bugs.

Great work!

[Toltekradiation]

hi guys, thanks for the interest !
yes there is some room for experimentation !
but not so much cpu, so it seems we must keep it simple..
still finding my way through this, but yeah! i added foldback & xor distortion to this version.. + some tweaks and fine tuning around the sigmoid & distortion..

(edit : modified version with new foldback algo)

[Toltekradiation]

another version with some bug fixes :
all new filters can now be controlled with the matrix.
+ various tweak
i think i'm done for today 

[kyoto]

Toltekradiation, thank you very much for your work -- goodbye weekend 

[matrix12x]

The new filters sound great. I've been playing for the last hour and a half.
No crashes yet.

BTW, Where did the all-pass go?

[Toltekradiation]

hi, another version with a fix for lp2 & hp2 : better behaved self oscillation
@matrix12x : the allpass filter is used in the "Pann" filter ; the "pos" parameter is the filter cutoff and it's not very interesting
as i understand, the allpass filter is more a building block to create phaser, reverb.. it's not really worth alone.
I will study this a bit more, and i would also like to add some time dependant fx like delay, phaser, comb filter, chorus.. i must first figure how to know the amount of ram left for this 
another thing i will investigate is the possibility to add the "filter reso" parameter to the matrix destination list..

[Xavier]

I haven't tried it yet, but thanks a lot for sharing this. 

[Toltekradiation]

hi Xavier,
thanks to you to make this even possible 
in this version, i added a waveshaper in some of the new fx to add a little bit more grit.
i had to rollback some of my improvements as the cpu overload..
now with some care and optimizations, all fx works well with 14 voices playing !

[Toltekradiation]

and another one with more fx :
wrap : extreme distortion, ready for metal ?
swap : adaptation of the puredata swap~ https://git.iem.at/pd/zexy/blob/master/src/swap~.c
swap work best on simple monophonic sine wave but it can work as a dirty distortion too

[matrix12x]

good work. I'm enjoying wrap.

I played with this latest version for the last hour our so and no crashes or other bugs so far.

[kyoto]

great work man! - thank you very much 

[superfake]

Thanks for the great work!
Is it possible to implement a 6db and 12db low-pass filter?
Is it also possible to save performance parameters in a patch?

[Zenman]

Very cool. I´ll try it. Thank you!