Dear List,

I wonder for quite a while if it is possible to build lowpass- and highpassfilters with the existing opcodes in Csound which do sound and behave like the analog voltage controlled filters of the seventies and eighties. Especially I do like the feedback and self oscillation of those. I tried the opcodes Moog VCF, Moogladder and Rezzy and Lowpass 2 -  but never got even close to the desired sound, even if I cascaded some of them one after another. Is it really that difficult to emulate them in the digital realm or can someone maybe point me to nice sounding examples that came close?

Best,

Jan Jacob


sound         |         movement          |          object         |          space
sonic architecture       |        site: http://www.sonicarchitecture.de
spatial electronic composition  |  higher order ambisonic music

Csound mailing list
Csound@listserv.heanet.ie
https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
Send bugs reports to
        https://github.com/csound/csound/issues
Discussions of bugs and features can be posted here

Did you also try lpf18?
...one if my favourites

Emulating these things is indeed difficult because our ears are quite
good and hear the tiny analog nonlinearities that typically are not
captured in digital emulations. For example in analog synths a click
is a kind of dry snap, quite beautiful really, but a digital impulse
is a much shorter and less interesting sound.

Similarly for square waves, an analog oscillator has all sorts of
little bends and kinks in the waveform, easily visible in an
oscilloscope, that are not captured by simply stacking up sine tones
as we usually do for a bandlimited square wave.

All of these things can indeed be modeled by digital signal
processing, but it takes a long time to figure them all out and
frequently requires expert knowledge of DSP.

It's easy if you just take the impulse response of the analog system,
and that's why convolution reverbs are so common, it works very well
and is relatively easy to implement. Modeling filters and analog
oscillators is much much harder because instead of an impulse
response, you typically need a set of differential equations that need
to be turned into numerical solutions.

To see what happens when a Csounder gets serious and makes this work,
look at the Spanish guitar emulation by Jeff Livingston in
csound/examples/CsoundAC.csd. I would say Livingston's guitar model is
roughly the equal of any Sony or Yamaha model I have heard.

To get a realistic sounding analog synth, a Moog clone, you would have
to do something of similar complexity but it would probably be harder
because it's possible to develop physical intuition about what's
happening in the guitar but for me, anyway, I don't have such great
physical intuition about what's happening in the circuits of a modular
Moog. If I had one to actually play with and compare with my emulation
I could probably do it but it's certainly more than a few days of
work.

Best,
Mike



-----------------------------------------------------
Michael Gogins
Irreducible Productions
http://michaelgogins.tumblr.com
Michael dot Gogins at gmail dot com


On Wed, Jan 6, 2016 at 11:09 AM, Oeyvind Brandtsegg  wrote:
> Did you also try lpf18?
> ...one if my favourites
>
> 6. jan. 2016 17.07 skrev "Jan Jacob Hofmann" :
>>
>> Dear List,
>>
>> I wonder for quite a while if it is possible to build lowpass- and
>> highpassfilters with the existing opcodes in Csound which do sound and
>> behave like the analog voltage controlled filters of the seventies and
>> eighties. Especially I do like the feedback and self oscillation of those. I
>> tried the opcodes Moog VCF, Moogladder and Rezzy and Lowpass 2 -  but never
>> got even close to the desired sound, even if I cascaded some of them one
>> after another. Is it really that difficult to emulate them in the digital
>> realm or can someone maybe point me to nice sounding examples that came
>> close?
>>
>> Best,
>>
>> Jan Jacob
>>
>>
>> sound         |         movement          |          object         |
>> space
>> sonic architecture       |        site: http://www.sonicarchitecture.de
>> spatial electronic composition  |  higher order ambisonic music
>>
>> Csound mailing list
>> Csound@listserv.heanet.ie
>> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
>> Send bugs reports to
>>         https://github.com/csound/csound/issues
>> Discussions of bugs and features can be posted here
>
> Csound mailing list Csound@listserv.heanet.ie
> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to
> https://github.com/csound/csound/issues Discussions of bugs and features can
> be posted here

Csound mailing list
Csound@listserv.heanet.ie
https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
Send bugs reports to
        https://github.com/csound/csound/issues
Discussions of bugs and features can be posted here

Hey hey Jan!
Jan Jacob Hofmann, Jan 6 2016:
...
> I wonder for quite a while if it is possible to build lowpass- and highpassfilters with the existing opcodes in Csound which do sound and behave like the analog voltage controlled filters of the seventies and eighties.
...
Can you load LADSPA plugins into your local Csound? Have you considered Fons Adriaensen's MCP plugins? I've heard it said, by someone, who actually owned a Moog Voyager, that half the time he used the supplied filters and oscillators from Fons' plugins, even though he spent top dollar for his Moog and loved it dearly.

Have you looked at nlfilt and perhaps the biquad filters? They aren't exactly, what you are looking for, but they can be used to more closely customise a sound you have in mind. Beyond small variations on the Csound manual examples, I didn't experiment with them, since I didn't have the time to read up on the matter thorroughly enough.

Ta-ta
----
Ffanci
* Homepage: https://freeshell.de/~silvain
* Twitter:  http://twitter.com/ffanci_silvain
* GitHub:   https://github.com/fsilvain

Csound mailing list
Csound@listserv.heanet.ie
https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
Send bugs reports to
        https://github.com/csound/csound/issues
Discussions of bugs and features can be posted here

A nice job for a rainy Saturday: port those Ladspa plugins as Csound opcodes.

Victor Lazzarini
Dean of Arts, Celtic Studies, and Philosophy
Maynooth University
Ireland

> On 6 Jan 2016, at 16:59, Ffanci Silvain  wrote:
> 
> Hey hey Jan!
> Jan Jacob Hofmann, Jan 6 2016:
> ...
>> I wonder for quite a while if it is possible to build lowpass- and highpassfilters with the existing opcodes in Csound which do sound and behave like the analog voltage controlled filters of the seventies and eighties.
> ...
> Can you load LADSPA plugins into your local Csound? Have you considered Fons Adriaensen's MCP plugins? I've heard it said, by someone, who actually owned a Moog Voyager, that half the time he used the supplied filters and oscillators from Fons' plugins, even though he spent top dollar for his Moog and loved it dearly.
> 
> Have you looked at nlfilt and perhaps the biquad filters? They aren't exactly, what you are looking for, but they can be used to more closely customise a sound you have in mind. Beyond small variations on the Csound manual examples, I didn't experiment with them, since I didn't have the time to read up on the matter thorroughly enough.
> 
> Ta-ta
> ----
> Ffanci
> * Homepage: https://freeshell.de/~silvain
> * Twitter:  http://twitter.com/ffanci_silvain
> * GitHub:   https://github.com/fsilvain
> 
> Csound mailing list
> Csound@listserv.heanet.ie
> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
> Send bugs reports to
>       https://github.com/csound/csound/issues
> Discussions of bugs and features can be posted here

Csound mailing list
Csound@listserv.heanet.ie
https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
Send bugs reports to
        https://github.com/csound/csound/issues
Discussions of bugs and features can be posted here

I took a look at the source. Shouldn't be much work. I'll not have time to do this for a few weeks, but would like to try.

I took a look at the source. Shouldn't be much work. I'll not have time to do this for a few weeks, but would like to try.

On 9 Jan 2016 21:53, "Luis Jure" <ljc@internet.com.uy> wrote:

Victor Lazzarini <Victor.Lazzarini@NUIM.IE> escribió:

A nice job for a rainy Saturday: port those Ladspa plugins as Csound opcodes.

i haven't tried them (i don't use ladspa plugins), but if they are as good as they say, it would be great to have them as csound opcodes, indeed. anyone with rainy saturdays?

Csound mailing list
Csound@listserv.heanet.ie
https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
Send bugs reports to
       https://github.com/csound/csound/issues
Discussions of bugs and features can be posted here

Csound mailing list Csound@listserv.heanet.ie https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to https://github.com/csound/csound/issues Discussions of bugs and features can be posted here