PreenFM Forum

PreenFM => PreenFM2 => Topic started by: Toltekradiation on August 11, 2019, 12:57:50 AM

Title: New filters
Post by: Toltekradiation on August 11, 2019, 12:57:50 AM
hi,
I finally dared to dig the preenfm code, and, it was worth it  8)
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)
Title: Re: New filters
Post by: kyoto on August 13, 2019, 09:23:16 PM
wow - great - now will try ;)
Title: Re: New filters
Post by: matrix12x on August 14, 2019, 03:22:47 AM
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!
Title: Re: New filters
Post by: Toltekradiation on August 14, 2019, 10:41:22 PM
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)
Title: Re: New filters
Post by: Toltekradiation on August 15, 2019, 02:47:23 PM
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  :P
Title: Re: New filters
Post by: kyoto on August 15, 2019, 05:04:16 PM
Toltekradiation, thank you very much for your work -- goodbye weekend  8)
Title: Re: New filters
Post by: matrix12x on August 16, 2019, 12:52:29 AM
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?
Title: Re: New filters
Post by: Toltekradiation on August 16, 2019, 12:36:59 PM
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..
Title: Re: New filters
Post by: Xavier on August 17, 2019, 08:49:58 AM

I haven't tried it yet, but thanks a lot for sharing this.  :)
Title: Re: New filters
Post by: Toltekradiation on August 17, 2019, 11:46:23 AM
hi Xavier,
thanks to you to make this even possible  :D
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 !
Title: Re: New filters
Post by: Toltekradiation on August 18, 2019, 01:04:25 PM
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 ;)
Title: Re: New filters
Post by: matrix12x on August 18, 2019, 07:34:57 PM
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.
Title: Re: New filters
Post by: kyoto on August 18, 2019, 09:09:25 PM
great work man! - thank you very much  8)
Title: Re: New filters
Post by: superfake on August 19, 2019, 02:20:39 PM
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?
Title: Re: New filters
Post by: Zenman on August 20, 2019, 09:31:57 PM
Very cool. I´ll try it. Thank you!
Title: Re: New filters
Post by: Toltekradiation on August 20, 2019, 11:44:31 PM
@superfake : i tried to get that smoother filter but could not do it right for some reasons ??? .i fear i'm not so good at this kind of programming, i could nearly implement this one https://www.musicdsp.org/en/latest/Filters/23-state-variable.html, which is cpu friendly, but i could not get rid of a high pitch noise in the sound. Those filter equations are quite a mystery for me, i must say.
About the performance parameters, i'm not sure it's possible as it may change the patch structure, must have a closer look...
Title: Re: New filters
Post by: kaosbeat on August 22, 2019, 01:42:38 PM
Great!

will this work with the Eurorack version (which has CV1-4 settings in the firmware?)

wanna try
Title: Re: New filters
Post by: kyoto on August 22, 2019, 02:34:13 PM
@Xavier
please add this extra types of filters to your software editor 🙏
Title: Re: New filters
Post by: Megalomidiac on August 22, 2019, 05:24:10 PM
I can't update any higher version than p2_pvi_210o.bin. All newer versions don't boot, display stays black and no MIDI or sound response.
Have bootloader 1.11. Any suggestions?

There is the preenF405 board instead of the Cerb40 in my PreenFM2, if that makes a difference.
Title: Re: New filters
Post by: Toltekradiation on August 22, 2019, 09:18:45 PM
hi,
@kaosbeat : it should work as i made changes on the last official sources.
@kyoto: i think that the new filters should be merged first in the master : the editor is for the master version.
 you should consider what i've done so far as a work in progress, i'm still playing with it and it's not bug free. Maybe later, Xavier might want to merge some of the fx when they are stable..
anyway, here is a new version with a bug correction in the hp2 :) + some changes : i removed the swap fx which was too harsh for my taste ; i'm playing now with the idea of bit mangling in 2 new fx texture1 & 2, well, i might as well have named it distortion33 & 68  ;D.
Another change in this version is the filters lp2 & hp2 offset changed to match the original cutoff of lp & hp : in fact, they now sound quite the same, they are maybe just a bit smoother, so lp2&hp2 might replace lp&hp if you guys think it's worth..
@Megalomidiac : that's weird as i also use the preenF405 board with bootloader 1.11 without problem, don't know what can be the cause. :-\
Title: Re: New filters
Post by: Xavier on August 22, 2019, 09:49:20 PM
@kaosbeat : If you flash this firmware on a eurorack you'll lose the eurorack specific features.

@Toltekradiation : FYI the eurorack version is in the "adcIn" git branch : https://github.com/Ixox/preenfm2/tree/adcIn

@megalomidiac : maybe the name is too long if you flash from the the USB key.
Rename it to 8 charaters + ".bin" and try again.

I'll eventually merge this modification into the main branch, add the filters in the editor and release both main and Eurorack version. I just cannot say when  because i have no idea ;)


Title: Re: New filters
Post by: kyoto on August 22, 2019, 09:56:42 PM
guys - thank you very much for your work  ;)
new filters - a breath of fresh air into the sound of this wonderful synthesizer
and waiting this new filters in the new software editor

regards
Title: Re: New filters
Post by: Megalomidiac on August 22, 2019, 10:54:13 PM


@megalomidiac : maybe the name is too long if you flash from the the USB key.
Rename it to 8 charaters + ".bin" and try again.

That was the next thing, I wanted to test, but no luck.
I will check tomorrow, if the USB key is bad and will report, thank you!
Title: Re: New filters
Post by: Megalomidiac on August 23, 2019, 04:47:56 PM
It now works perfectly, it was indeed a faulty USB key! Thank you all for your work, it is awesome. Played a few presets on it a few minutes ago with a nice plate reverb :)
Title: Re: New filters
Post by: kylelandstra on August 23, 2019, 09:42:58 PM
Hello!

Could someone provide steps to upgrade this for me?  I have upgraded my PreenFM2 to 2.10 o but do not know how to adjust the source code to add these new filters.  Is anyone able to "dumb down" the steps for someone like me?  I would appreciate it!  :) 

I get lost at "add the bin..."


Take care,
Kyle
Title: Re: New filters
Post by: Xavier on August 24, 2019, 12:14:10 PM
Hello!
Could someone provide steps to upgrade this for me?  I have upgraded my PreenFM2 to 2.10 o but do not know how to adjust the source code to add these new filters.  Is anyone able to "dumb down" the steps for someone like me?  I would appreciate it!  :) 
Kyle

Hi,
You don't have to compile the firmware.
Download the latest firmware attached to Toltekradiation's message just above.
Easiest way to upgrade is is to put in on your USB key and to flash from it. Step 1&2 here : http://ixox.fr/preenfm2/manual/upgrade-firmware/
Title: Re: New filters
Post by: kylelandstra on August 24, 2019, 05:44:40 PM
Oh wow, I didn't even see the attachment  :-[ Haha thank you.  So excited!
Title: Re: New filters
Post by: Toltekradiation on August 24, 2019, 08:14:22 PM
hey, wait !
there is another version ;D
this one add some playability : i rounded the volume to avoid big changes while trying fx,
reworked the xor fx ; i didn't like too much the previous version..
+ 2 experimental filters based on lowpass & xor operation
Title: Re: New filters
Post by: kaosbeat on August 25, 2019, 02:01:49 PM
 @toltekradiation would it be crazy for you to merge your changes with the Eurorack version as Xavier described in an earlier posty? no idea where to start...

Quote
FYI the eurorack version is in the "adcIn" git branch : https://github.com/Ixox/preenfm2/tree/adcIn

Title: Re: New filters
Post by: Toltekradiation on August 25, 2019, 08:58:49 PM
ok, i finally understood how to checkout a git branch,  ;)

here is the adcIn version as attachment
Title: Re: New filters
Post by: Toltekradiation on August 25, 2019, 09:00:55 PM
and then the master version.

while i was at it, i added a new filter : a crossfade between lp & hp across the frequency range.
enjoy !
Title: Re: New filters
Post by: baxgas on August 26, 2019, 01:34:12 PM
Wow, sounds Funtastick! Looking forward to try it out!

Thanks for improving this great little synth!
Title: Re: New filters
Post by: kaosbeat on August 26, 2019, 02:11:39 PM
I flashed it onto my Eurorack PreenFM2... so far so good
Sounds great, lot's of extra filters and CV mappings work!
no crashes or glitches so far

really great stuff

 :o  ;D
Title: Re: New filters
Post by: baxgas on August 26, 2019, 02:46:36 PM
The Filter improvements are really-really useful, thank you! I also found the original PreenFM2 Filter algorithms a bit weak...

A few thoughts:
- some infos about the implemented filters and the parameters they use (at parameters Cutof/Resonance) could be useful, so that it is easier to understand what is what (maybe at the git page  README.md?)
- any chance to implement some Flanger, Phaser, Chorus algorithms? Maybe even Delay and Reverb? Or even combination of Modulation/Delay effects (but I understand there could be some processing-power limitations)
- I don't know if it is possible, but could be very nice to modulate the Resonance (or any second) parameter also from the Modulation Destinations?

Keep up the good work!

(PS: hope these improvements will also get in the official version)
Title: Re: New filters
Post by: Toltekradiation on August 26, 2019, 11:55:43 PM
hi guys, thanks for the support !

added two new ones :
BP3 is another BP flavour
LPws is a distorted lowpass, to mix with the source to enhance presence

@baxgas : good idea, i modified the readme to give some infos about the fx (https://github.com/pvig/preenfm2)
about delays, phaser etc, these kind of fx require memory that we don't have left on the preen, i fear..
but you can already patch fm to sound like a chorus (kind of) with careful detuning, or simulate a delay with the free env 2 loop !
like this https://www.youtube.com/watch?v=GYFD1lmk-lo (https://www.youtube.com/watch?v=GYFD1lmk-lo)

i will have a second look at the possibility to modulate fx param 2 in the matrix, but at first sight it seemed quite some work..
Title: Re: New filters
Post by: baxgas on August 27, 2019, 09:26:11 AM
@Toltekradiation: Thanks for the infos!
Will check also the new Filters also. Btw. Are these flavours and different types just for testing and then at the end you'll leave the best one, or you plan to leave all of them?
Title: Re: New filters
Post by: Toltekradiation on August 27, 2019, 10:42:23 AM
@baxgas, yes it is quite crowded in the fx department now !
for me, the main use of filters is to fine tune the instruments, to make them work well with other instruments ; i want to use the preenfm in a minimal setup with a drum machine, the main output should be good enough as is, with its 4 instruments mixed. So i must cut the bottom of some, emphasize the mids of others, etc... to let the lead instrument have enough space ; this one can have some grit, unusual fx..

for now, i would nearly keep all, but I need to play with it more to be sure about this.
what one would you remove/keep ? what would be your use/need of the fx ?
Title: Re: New filters
Post by: baxgas on August 27, 2019, 04:53:32 PM
@Toltekradiation all the stuff is great, it really adds a lot to the richness of the FM synthesis
Haven't dug really much deep in all the uses (although my PreenFM2 is always on in my spare time, since you made these additions :-) ), but these are some experiences so far

- Txr1 and Txr2: seems just like adding some noise to the signal? Of course the filters will behave differently with different signals that are put through, so I believe the type of the source sound is also important.

- Can the Mix parameter (generally) be replaced to some filter changing function? (like eg. LPx1 that besides Frequency the other parameter changes the xor amount). I think these kind of effects are not like eg. Reverb/Delay or similar that dry/wet ratio is that important.

- Is it possible to implement algorithm for Notch type effects (inverse of Band-Pass, that it just removes the Frequency)

You are right about the mixing of the 4 instruments, it can really make a difference with the filtering. I also know that the PreenFM2 architecture is a bit limited in this regard, as it acts just at the end of the signal-chain as a per-channel filter/effect, although modulatable by the Modulation matrix. 
I wouldn't mind to have a lot of filters, why not :-) Just if some patches are saved with some effect, and they got replaced in the meantime, they will probably get back to the default, or switch to some other type.

As for the Chorus, and modulation effects, I know the trick of slight detuning, it is also very nice to detune a bit the modulator in comparison to the Operator, adds nice phasing effects that can turn to some waveshaping if modulated to more extremes. The FM is a great system for sound-mangling :-)
Title: Re: New filters
Post by: Toltekradiation on August 27, 2019, 10:45:22 PM
thanks for your insight,
the mix parameter was a quick way to use the parameter 2, but you're right, it can get better use. i will review the possibilities.
i'm currently working on a notch filter, which may be useful for sure :) (if i can get it working :P )
Title: Re: New filters
Post by: superfake on August 30, 2019, 02:03:01 PM
Thank you so much for the work! Preen plays with new colors.  8)

Is it possible to add the LP2 filter from firmware 1808 in addition?
I liked that the filter opened to higher frequencies.
The new version opens only up to about 7 kHz, like a standard LP filter.  :'(
In version 1808, the filter opened up to about 14 kHz - and that was good for brighter sounds.
Of course, it would be nice if the LP filter worked in the maximum range up to 20 kHz.  ::)
Title: Re: New filters
Post by: Toltekradiation on August 30, 2019, 08:48:58 PM
hi,
ok, i will try things with that in mind.

Title: Re: New filters
Post by: Toltekradiation on August 31, 2019, 01:50:49 PM
hi,
many thanks to @baxgas & @superfake to push me in the right direction, so in this version there is some more filters  :) :
Lp3 :  state variable filter, low pass mode
Hp3 : state variable filter, high pass mode
Bp3 : state variable filter, band pass mode
Peak :state variable filter, peak mode
Notc : state variable filter, notch mode
Bell :  state variable filter, boost if param amp > 0.5, else cut
BpDs: saturated bandpass filter

+ some rework on these fx to get a better use of the 2nd parameter  : Sat, Sigm, Fold, Wrap, Xor, Txr1, Txr2
+ the full range is back in lp2, hp2


Title: Re: New filters
Post by: superfake on August 31, 2019, 02:27:46 PM
Wow, thanks!  :o

At maximum gain, the filter is interestingly overloaded, the sound is somewhat similar to 303.
Oh, if it was possible to adjust the volume after the filter...  ::) for balance with other parts.

Here is an example. Used custom saw.
Title: Re: New filters
Post by: kyoto on August 31, 2019, 03:00:47 PM
@Toltekradiation - wow - great work man!!!   8) 8) 8)
Title: Re: New filters
Post by: pikseliahky on August 31, 2019, 04:10:46 PM
Thanks, great stuff! Is there a CVin version as well?
Title: Re: New filters
Post by: Toltekradiation on August 31, 2019, 05:10:08 PM
@pikseliahky : yes! here it is !
Title: Re: New filters
Post by: Toltekradiation on August 31, 2019, 05:12:09 PM
and here is the version with volume compensation fix for the SVF filters :D.
Title: Re: New filters
Post by: matrix12x on August 31, 2019, 11:32:15 PM
@Toltekradiation, Really great work.
Title: Re: New filters
Post by: Toltekradiation on September 02, 2019, 09:52:25 PM
well, it seems i can't help trying things :), and i find those filters really useful :
lowshelf & highshelf from https://cytomic.com/files/dsp/SvfLinearTrapOptimised2.pdf
Title: Re: New filters
Post by: Toltekradiation on September 02, 2019, 10:01:46 PM
adcIn version attached.
Title: Re: New filters
Post by: baxgas on September 03, 2019, 10:13:40 AM
@Toltekradiation Thanks, I'm really eagerly waiting to hear and test them! :-)

One thing I noted is that when I save the patches with the Filters, in the new version they are messed up, probably because of the numbered positions of the algorithms, and that they change eg. there are more filters before the Distortions?

Also, with the new OS, the parameter changes seem much more sluggish, eg. I have 4 Channels sequenced and I try to change a paramter and it increments only a few steps then stops, also the Inst change is much slower, with a blink of the LCD. Maybe these are already too much for the processor to handle? :-(

Can the filename of the bins be renamed so the PreenFm2 truncation of the characters is a bit more informative?
Title: Re: New filters
Post by: Toltekradiation on September 03, 2019, 11:52:45 AM
@baxgas, sorry for the messy project handling :-[. Yes, that's because i added the new filters before distortions..
the processor is now a bit more busy than it was, i fear. i will now try to optimize my code more.
Title: Re: New filters
Post by: baxgas on September 03, 2019, 06:34:50 PM
@Toltekradiation I understand there is a limitation in processing power... btw. you used the overclocked version (210o), but maybe the "regular" version is a bit less demanding? (just an idea)
Title: Re: New filters
Post by: Toltekradiation on September 04, 2019, 06:23:17 PM
hi @baxgas, thanks for the suggestion, i tried the regular version, but no luck..
so i changed my testing procedure, to be closer from real use case, and, yes, sadly, the cpu started to overflow very quickly. so, some radical optimisations needed :o !
i removed oversampling on lot of filters ; in a mix you won't hear the change i guess ;)
+ removed lot of waveshaping, well, the good news is that it sound cleaner now :D (or cheaper :()
now it seems to work well with a 4 track sequencing. it still may overflow if you really insist, so i will try to free more cpu cycle if i can..
i may remove lp2 & hp2 as these are still oversampled, and now lp & lp3 seems to be enough.
Title: Re: New filters
Post by: Toltekradiation on September 05, 2019, 10:08:10 AM
good news, i found the "float cast" optimization and it make a big difference :D,
i could bring back oversample on the lp3, hp3, bp3, peak filters !
for a test, i could have 4 parts running fast with per step program change, and it kept smooth !
the other optimizations was a good thing anyway.. 8)
Title: Re: New filters
Post by: Toltekradiation on September 05, 2019, 10:14:23 AM
here is the adcIn version :)
Title: Re: New filters
Post by: baxgas on September 05, 2019, 03:17:27 PM
@Toltekradiation Thank you for the improvements, now it works really smoothly at my PreenFM2, fantastic  :)
I will test it thoroughly and let you know if I find some more tips for improvement, but for now it seems really-really great!
One thing I noticed with the file-naming is that the OS Flasher recognises the .bin only if it's filename is starting with p2_ Otherwise it is great you renamed them, so the filename truncation is much more informative!

Just a question, will the position of the effects move in some future version (planning adding some more), so I can track which parameters were saved with the patches? Now the old patches load in with a bit different FX, I guess because it saves the ID, and it changes if some new are added before.

Thank you so much for the great job you done with these improvements!
Title: Re: New filters
Post by: kyoto on September 05, 2019, 03:28:52 PM
good work - thank you very much ;)
Title: Re: New filters
Post by: Toltekradiation on September 05, 2019, 06:38:15 PM
hi guys!
i'm very glad you're enjoying my work ! :D
i may leave the version like that, but don't hesitate to suggest ideas or requests,
it seem usable enough, so, i don't plan to add any other fx or change the fx list.
maybe polish it a bit, but would have better to really dive into sound design now ::).
Title: Re: New filters
Post by: maki on September 05, 2019, 07:50:45 PM
Hello, could you then make a tracking generator for each slot in Modulation Matrix?
Title: Re: New filters
Post by: Toltekradiation on September 05, 2019, 09:11:33 PM
hi @maki, i guess you would like to have the parameter 2 available in the modulation matrix ?
if so, i tried to, but it failed.. (exception crash) because of my lack of understanding the structure of some part of the code (matrixParameterRow), and, according to the code comment( https://github.com/pvig/preenfm2/blob/master/src/synth/SynthState.cpp#L314), 8 destination target were removed in firmware 2.0, i think for a good reason, so i gave up...
for now, i use my digitakt to control param2 by CC, so i don't think i will dig this, sorry.
or maybe i misunderstood, what do you mean by tracking generator ?
Title: Re: New filters
Post by: maki on September 06, 2019, 06:11:52 AM
Tracking generator, as implemented in Oberheim Matrix, Alesis Ion, Alesis Micron, Akai Miniak, called "table" in Alesis Fusion and "edir user curve" in Control assign in Yamaha Montage/Modx is a user defined respons on input in modulation matrix. In this case, instead of having one breakpoint and a few functions left and right form the break point, user could define whatever 8,16 or 32 points response curve, giving much more detailed response. On my Miniak I can distribute fm over the keyboard on many more ways than cust according to a few math curves.This function alone gives tremendous variety of flavours. It looks very simple, like an array of 8,16 or 32 places, each containg a user editable number in range from -127 to +127.
Title: Re: New filters
Post by: baxgas on September 06, 2019, 07:22:41 AM
@Toltekradiation definitely dive in to sound design, you deserve a bit fun also after the hard work on engineering ;-)
I hope these improvements will also get in to the "official" OS. @Xavier?
Title: Re: New filters
Post by: Toltekradiation on September 06, 2019, 11:21:00 AM
@maki : thanks for the info, i wasn't aware of this. It may be possible to add a 4 points fm shaper on each slot, would have to make a poc.
Anyway, it's too much work for me at the moment, maybe in some months.
Title: Re: New filters
Post by: maki on September 06, 2019, 08:38:21 PM
Toltekradiation, if tracking generator is a to big task now, but you still have some extra energy to work, why not implement 1)paraphonic properties in Preenfm2? It seems simple: a counter counts the number of held/active notes and this value changes something in a modmatrix output.
2)Or you could subtract incoming notes and use those values further in modmatrix outputs.
3)Or you could use the time difference between held notes to change something in modmatrix output.
4)Or you could measure the speed of incomming cc events to change something in modmatrix output.
There are so many unused, simple synthesis ticks we musician could use but are not available else in the world, waiting for a developer to implement.
Title: Re: New filters
Post by: Toltekradiation on September 06, 2019, 10:30:21 PM
@maki : thanks for the ideas, these may be fun to try for some pseudo algorithmic music ::)
i would also like to have polyphonic glide, maybe some sort of unison, and step sequence advance with note received.. i may try all those things later.. for now, i prefer to stay in the filter/fx context, to fullfill this part before starting something else.
Title: Re: New filters
Post by: superfake on September 07, 2019, 12:02:43 AM
Hello, @Toltekradiation!
Glad the work continues.  8)
I apologize if I tear you from the sound design.  :)

I did some tests ...
I understand that I am probably asking for the impossible...  ::)
So ... is it possible to return the sound of SIGM and FOLD effects from firmware 3108, while maintaining processor resources, as in firmware 0509?

I don’t know how the other guys have, but for me these effects in the latest firmware do not sound as tasty as in 3108.
3108 is cool, but it's too easy to make the processor cry with it... :'(

In the demo below, the SIGM effect from version 3108 sounds better in the lower range, but at the same time, the sound is interestingly compressed - the attacks are smoothed out. And I really like it.
I could not configure the SIGM effect in firmware 0509 so that it sounded the same as 3108.
The FOLD effect from 0509 sounds quieter and somewhat strange.

But, at the same time, I want to have both versions of the SIGM effect. :D From firmware 3108 and 0509. Because on some other sounds, the new version also gives an interesting result.

WRAP, in my opinion, also sounds strange ... :-X


applying the result of my little test.
In tests, effects start from the same values. The remaining settings, including volume, are also the same.


Fold from 3108
https://clyp.it/rcbwg5sv

Fold from 0509
https://clyp.it/lz3nmtoj

Sigm from 3108
https://clyp.it/to1ho1l3

Sigm from 0509
https://clyp.it/fak0frz3
Title: Re: New filters
Post by: maki on September 07, 2019, 07:22:16 AM
Toltekradiation, I am jealous on programmers ability to change an instrument from the ground up, the way they want. I have many artistic ideas but no programming skills. Could you, please, describe your "working enviroment", tools and software you used to change Peenfm2 the way you want. Thank you.
Title: Re: New filters
Post by: Toltekradiation on September 07, 2019, 10:13:45 AM
@superfake , thanks for the feedback,
yes you're right, i prefer the previous version as well   :D
in this version the 3108 sound is back on fold and sigmoid ! and it's not so cpu hungry after all :)
i also fixed a problem on lp2, hp2 when extremely modulated, the filter went off..

@maki, you don't need much software to try things on the pfm2 :
https://code.visualstudio.com/ to edit the code
arm-gcc version 4.7 (see https://github.com/Ixox/preenfm2 )
and git would be helpful but not mandatory (https://git-scm.com/)
but if you're not much into programming, i would suggest you to test puredata, or easier, get an axoloti (http://www.axoloti.com/) and have a ton of fun creating crazy things  ;) !
Title: Re: New filters
Post by: Toltekradiation on September 07, 2019, 10:15:10 AM
adcIn version
Title: Re: New filters
Post by: superfake on September 07, 2019, 01:48:36 PM
Merci beaucoup!
Title: Re: New filters
Post by: superfake on September 08, 2019, 02:29:35 PM
Hello, @Toltekradiation!
Something is wrong...  :o
SIGM and FOLD in 0709 do not sound like in 3108.
SIGM does not have such energy in the lower range as in firmware 3108.
FOLD also does not sound like 3108 - it still has clipping, plus there was a problem with panning when the FREQ parameter changes.
 :'(

Here is the test result:

Fold 0709
https://clyp.it/au51xft2

Fold 3108
https://clyp.it/04tw0a2d

Sigm 0709
https://clyp.it/b2diewso

Sigm 3108
https://clyp.it/vniflitk


Of course, without effects, patches sound the same in both firmware versions.

Anyway, thanks for your work.  8)
Title: Re: New filters
Post by: baxgas on September 08, 2019, 02:52:55 PM
@Toltekradiation, thanks, I flashed the new OS, and it seems working nicely (no lags). I didn't test every FX thoroughly so can't really tell the difference for now, but if it improved – so better :)

Now what I would find an improvement, if we have so sophisticated FX section, is to have a bit more interaction with the Envelopes in the Matrix (eg. I always use Env1 for interaction with the Filter Freq on Note-Events), but maybe it is more a task for Xavier?
I think it would be nice to have modulation destination to control Env1 speed, globally or by parameters (Attack, Decay, Release). This way the Not1 could be used for controlling Env1 speed – good for Keyboard tracking of Env1.
Also would be nice to make available the Filter Parameter2 (eg. Resonance) in the Mod-Matrix. It is available on CC#72 btw.
Title: Re: New filters
Post by: Toltekradiation on September 11, 2019, 06:26:18 PM
@superfake : sorry, my bad, the rollback was not well made, now it should be ok.
Title: Re: New filters
Post by: Toltekradiation on September 11, 2019, 06:26:54 PM
adcIn version
Title: Re: New filters
Post by: superfake on September 13, 2019, 01:01:33 PM
@Toltekradiation, thank you very much!
I'm testing... while everything works fine  :)
Title: Re: New filters
Post by: Toltekradiation on September 13, 2019, 11:02:34 PM
i was not fully satisfied with the LPx1 & 2 fx, so here is a reworked version : in these, i replaced the mix parameter by a fold parameter ::)
Title: Re: New filters
Post by: Toltekradiation on September 13, 2019, 11:04:26 PM
adcIn version
Title: Re: New filters
Post by: baxgas on September 24, 2019, 09:17:11 AM
@Toltekradiation Thanks!
Didn't use much the LPx1-2 filters so far, so can't tell, but Fold adjustable parameter seems nice addition instead of the Mix
Title: Re: New filters
Post by: Toltekradiation on September 25, 2019, 09:39:22 PM
@baxgas, yes the fold parameter add more weirdness to an already weird fx :).
but for a more common use, i made some minor changes to the resonance of some filters to make it cleaner : it did not work so well in a polyphonic situation.
So i added two fx for that ; LpSn & HpSn, which are soft to medium distortion. the signal is not crushed like with others distortion when you play many notes.
i like to use LpSn on sine based pads : there is a sweet spot that give a nice analog feel ;)
Title: Re: New filters
Post by: Toltekradiation on September 25, 2019, 09:40:10 PM
adcIn version
Title: Re: New filters
Post by: Xavier on September 26, 2019, 10:42:53 AM

Thanks for continuing working on that  :)
I hope to have some time in the near future to really take a look.

Have you trids to use the DEBUG part that show the CPU usage of the audio loop ?
https://github.com/Ixox/preenfm2/blob/master/src/synth/Synth.cpp#L187

The 2 Last algos are the ones that use the more CPU.
And using the LFO, env1 & 2 and Step seqs in the matrix also takes some CPU.
Always good to check the 8 voices with all LFOs and a filter can still play correctly.

That can help to detect if one of the filter takes more CPU then it should.

Xavier
Title: Re: New filters
Post by: Toltekradiation on September 26, 2019, 10:15:20 PM
 :-[ Sorry, there was a bug in the two new fx, i replaced the two files with fixed version in previous posts.. they now sound as it should.
@Xavier, thanks for the hints, and the cpu usage will be very very useful ! but unfortunately i have missed something as the displayed % was stuck at 0 when i tested.. i will investigate more this weekend.
Title: Re: New filters
Post by: Xavier on September 27, 2019, 08:48:37 AM
@Xavier, thanks for the hints, and the cpu usage will be very very useful ! but unfortunately i have missed something as the displayed % was stuck at 0 when i tested.. i will investigate more this weekend.

Not sure if you set DEBUG=1 or if you just removed the line above.
But :
https://github.com/Ixox/preenfm2/blob/master/src/synth/Synth.cpp#L121
and
https://github.com/Ixox/preenfm2/blob/master/src/synth/Synth.cpp#L185

Must also be enabled here :
https://github.com/Ixox/preenfm2/blob/master/src/hardware/dwt.h#L67





Title: Re: New filters
Post by: Toltekradiation on September 29, 2019, 09:34:37 PM
yes it work fine now ! thanks !
it allowed me to fix some performance issues i wasn't aware of ;)
Title: Re: New filters
Post by: Toltekradiation on October 06, 2019, 01:01:09 PM
here is a version with 3 more filters, for sound design and phasing fun :)

changes are :

Not3 :
  triple notch filter, Sprd to spread the 2 poles around the center frequency
Ap3 :
  all pass triple filter, Sprd to spread the 2 poles around the center frequency
Ap3b :
  all pass triple filter, resonant version, Sprd to spread the 2 poles around the center frequency

Reworked pann fx :
  stereo placement tool : pos = panning, sprd = 3 x pole spread

Slight modification of the Txr1&2, LPx1&2
Title: Re: New filters
Post by: Toltekradiation on October 06, 2019, 01:02:05 PM
adcIn version