MeldaProduction

Whywhy · Post by **Whywhy** » Fri Feb 21, 2020 7:16 am

It's about the filter topology: biquad, zdf...
And the modulation.
Check this links :
[viewtopic.php?t=461189#p6437587]

[viewtopic.php?f=33&t=523958&hilit=Zdf]

[https://www.google.fr/url?sa=t&source=w ... mZe-aSnFKN]
Msf's filters can work really well in some situations and not work in others.
We can find online zdf filter code, free to implement and use and they sound really good.

operator · Post by **operator** » Fri Feb 21, 2020 10:05 am

Whywhy wrote: Fri Feb 21, 2020 7:16 am We can find online zdf filter code, free to implement and use and they sound really good.

Please Vojtech...

Nspace · Post by **Nspace** » Fri Feb 21, 2020 8:06 pm

There was a detail at the recently re-launched ARP 2600 FS by Korg, that got my attention.
It being a replica of the 70s original includes some new features like an arppegiator, aftertouch, FS full size keys but interestingly it also has a 4-pole Voltage Controlled Filter (VCF). A feature that was present only at the first units sold. It had to be eliminated in subsequent units to avoid legal problems, because it was a close design to a standing Moog patent.

But enough time has passed already and Korg and ARP and Melda are now able to utilize it together with many other designs, because either patents have expired or coveted non-patented designs had become available.

Luckily for us, patents do secure monopolies to inventors but only for a while, so they may recoup a reasonable gain for the investment.
After that lapse, those creations are for the world to benefit.
At 2020 we are truly

gifted.

MeldaProduction · Post by **MeldaProduction** » Sun Feb 23, 2020 11:02 pm

Whywhy wrote: Fri Feb 21, 2020 7:16 am It's about the filter topology: biquad, zdf...
And the modulation.
Check this links :
[viewtopic.php?t=461189#p6437587]

[viewtopic.php?f=33&t=523958&hilit=Zdf]

[https://www.google.fr/url?sa=t&source=w ... mZe-aSnFKN]
Msf's filters can work really well in some situations and not work in others.
We can find online zdf filter code, free to implement and use and they sound really good.

I'll check the links. Did yo see the ZDF code somewhere? I must say I just have way too many things on my plate, so studying ZDF maths isn't an option.

Chandlerhimself · Post by **Chandlerhimself** » Mon Feb 24, 2020 4:14 am

MeldaProduction wrote: Sun Feb 23, 2020 11:02 pm
Whywhy wrote: Fri Feb 21, 2020 7:16 am It's about the filter topology: biquad, zdf...
And the modulation.
Check this links :
[viewtopic.php?t=461189#p6437587]

[viewtopic.php?f=33&t=523958&hilit=Zdf]

[https://www.google.fr/url?sa=t&source=w ... mZe-aSnFKN]
Msf's filters can work really well in some situations and not work in others.
We can find online zdf filter code, free to implement and use and they sound really good.
I'll check the links. Did yo see the ZDF code somewhere? I must say I just have way too many things on my plate, so studying ZDF maths isn't an option.

I don't know how much this will help, but someone apparently shared some code here on kvr years ago, although I think its in java. Perhaps this will help.

viewtopic.php?t=368466

Here is another one that might be of interest
http://community.axoloti.com/t/diy-zero ... ilter/2009

No rush though. I like the current filters, but I think there is a need for others, especially filters that work at audio rate. Perhaps adding a basic version of the ZDFs into MTurbofilter would be enough if its possible to edit the feedback loops. Let others do the work when it comes to making them sound good.

Whywhy · Post by **Whywhy** » Mon Feb 24, 2020 6:17 am

Multichannel Svf:
https://gist.github.com/olilarkin/0d53e ... 4bb383c777

Zdf:
http://csound.1045644.n5.nabble.com/Csn ... 51102.html

Whywhy · Post by **Whywhy** » Tue Feb 25, 2020 9:05 am

viewtopic.php?f=33&t=350246&start=53

operator · Post by **operator** » Tue Feb 25, 2020 9:09 pm

Taaanks WhyWhy.

operator · Post by **operator** » Tue Feb 25, 2020 9:26 pm

Maybe this could complement the examples WhyWhy posted.

Urs Heckmann´s Blog:
https://urs.silvrback.com/one-pole-monster
https://urs.silvrback.com/one-pole-unlimited

KVR Thread: Cheap non-linear zero-delay filters
viewtopic.php?f=33&t=349859

Pdf: Non-Linear Digital Impelementation of the Moog Ladder Filter
https://pdfs.semanticscholar.org/c490/4 ... 53f6d8.pdf

MeldaProduction · Post by **MeldaProduction** » Tue Feb 25, 2020 9:47 pm

Interesting, thanks folks! It actually looks a bit too simple from some of the code, but who knows

operator · Post by **operator** » Fri Feb 28, 2020 12:54 pm

operator · Post by **operator** » Fri Feb 28, 2020 1:40 pm

operator wrote: Tue Feb 25, 2020 9:26 pm KVR Thread: Cheap non-linear zero-delay filters
viewtopic.php?f=33&t=349859

I was reading a little through this thread... and "Cheap" in the titel doesn´t mean that it is cheap. It is just the name of this methode named by KVR user mystran.

In this thread there are among other Urs Heckmann, Richard from Synapse and Andy from Cytomic talking and disgussing the filter methode/code... and the later one even corrected the code and suggested improvements. (others probably did aswell... I didn´t read all pages). Clemens, I think from u-he, even calls it "geniuse"... and Richard from Synapse calls it "brilliant" after first not liking it.

So I guess this thread may hold some interesting facts and the filter code is probably really good aswell.

Faiky · Post by **Faiky** » Tue Mar 17, 2020 9:20 am

Is there already help for MTurboFilter? I think a 16db acid filter should be no problem with a 12db +6 db filter? A curve of how the resonance behaves in relation to the frequency would be great (I don't know how something like this is described in a formula).
An analog function would be great here too, of course, but maybe a little more detailed. Feedback and detuning/fluttering could be adjusted separately. Then there are diode and transistor feedback distortion. Maby also control inaccuracies, fluctuations that only occur during movement.

But I guess you can do the whole thing in MFilter (unfortunately there is no analog emulation here and not per voice).

DarkStar · Post by **DarkStar** » Tue Mar 17, 2020 11:44 am

^^^^
If you click on the [?] in the Algorithm Editor you will see the syntax, but you'll have to know about filter design. (The Info says look at the presets but there aren't any yet!).

Faiky · Post by **Faiky** » Tue Mar 17, 2020 1:42 pm

Hm, okay, it sounds like this is going to be a school of its own, maybe not as easy as the designer from mturbo reverb? Syntax is all well and good, but the ingredients are missing. Lowpass, Bandpass, Allpass, okay self-explanatory. But i don't know how to write zdf, n-pole, IIR, Butterworth, Chebyshev, Cascade Filter, integrate Saturation Feedback and so on. Don't know if this would be possible.
I don't think you can create your own ZDF, rather combine different things like in TurboReverb? As I understand it, Vojtech himself doesn't yet know exactly where MTurboFilter will "end"

.

Have you already created or tested something DarkStar?

MeldaProduction

KVR Audio

MSF - Moog Style Filter / MTurboFilter