On 13-Nov-13 11:56, Marco Lo Monaco wrote:
I personally don’t think that automatic systems (DK) will be the
panacea of nonlinear modeling (even if everybody here is dreaming of
a realtime spice). Very often only a human can see patterns in
circuits and find shortcuts to simplify things.
+1
Besides the shortcuts, only a human can judge the critical aspects of
the analog model being discretized. Such as
- how precise should the component models be (e.g. if Ebers-Moll
transistor model is sufficient or not), where in principle this question
should be answered for each component separately
- whether the difference between parameter values of identically marked
components is having any critical effect
- whether the effect caused by a certain element of the model (e.g. a
nonlinearity) is musically insignificant (so that the element may be
dropped)
- to which extent we can assume independence of different parts of the
device (ignore the current leakage and other crosstalk)
and so on.
Perhaps, if in future we have computational powers several orders higher
than the currently available ones, such automatic system would be more
realistic, as we will be able to afford ridiculously precise and
detailed analog component models as the basis of our discretization. But
from my feeling it's still a long long way. And then, how important is
being able to automatically convert from analog schematics to digital? I
mean there has been some amount of brilliant engineering work to design
those analog devices, but it's not happening much more. So, after we
have modelled them all, we are not gonna need any further modelling.
OTOH, the lessons we learned from attempting to model those things (and
you learn more, if you do this "by hand" rather than by some automated
toolkit) should form an invaluable basis for the development of future
software. We can design *new* filters, effects, etc, which all are gonna
have "that analog sound". For that purpose of new designs (rather than
modelling the old stuff), I believe the *continuous-time* block-diagram
based approaches are more useful than the differential equations, as
they are offering a more intuitive view of the signal processing (YMMV).
The discrete-time block-diagrams are not that intuitive, in my opinion,
but then again, you don't need to use them, if you implicitly understand
the discretized version of the same analog block-diagram.
Regards,
Vadim
--
Vadim Zavalishin
Reaktor Application Architect
Native Instruments GmbH
+49-30-611035-0
www.native-instruments.com
--
dupswapdrop -- the music-dsp mailing list and website:
subscription info, FAQ, source code archive, list archive, book reviews, dsp
links
http://music.columbia.edu/cmc/music-dsp
http://music.columbia.edu/mailman/listinfo/music-dsp
