Re: [LAD] A small article about tools for electronic musicians

On Sat, May 1, 2010 at 8:57 PM, Tim E. Real <termtech@email-addr-hidden> wrote:

> On April 30, 2010 10:55:09 pm you wrote:
> > Tim E. Real wrote:
> >Wow, man! I just spent an hour playing with
> > Guitarix Distortion (ladspa plugin) +
> > caps C* Amp VTS (ladspa amp sim plugin)
> > in MusE's plugin rack.
> Silly me! I missed a piece of the puzzle. The C* Cabinet plugins.
> I was supposed to put a cabinet after the amp.
> Sounds even better now!
> It now approaches the type of sound that the JCM900 vst gives.
>
> > > Until now I have mostly been using SimulAnalog's famous JCM900 VST
> > > dll plugin under dssi-vst. (I do wish they would open-source those
> > > plugs!)
> >
> > Aha, it's for free :), http://www.simulanalog.org/GSuite.zip, until now
> > I didn't use VSTs when recording with Linux, but the web says, this VST
> > should be awesome,
> >
> http://www.google.de/#hl=de&ei=vJLbS_jPJc6YOMjj9JIH&sa=X&oi=spell&resnum=0&
> >ct=result&cd=1&ved=0CAUQBSgA&q=JCM+900+VST&spell=1&fp=af503062d682e13a
> >
> I have not tried their other plugins in the suite yet, but the following
> statement probably applies to them as well:
> That JCM900 vst is by far the most absolutely mind-blowingly realistic
> recreation of a Marshall amp *ever*. Most people agree.
> It is *THE* standard by which *all* other plugins are judged, commercial
> or free!
>
> Sadly, I just found out the hard way that it has a really nasty
> denormalization problem. It's so bad I may not be able to use it any more.
> People have tried fancy anti-denormalization plugins ahead of it, with no
> luck, apparently.
>
> MusE has a basic DC anti-denormalization feature, and it didn't help.
>

I completely agree with you: The JCM900 VST rocks! I've been using it a lot
on Windows, now I'm on the Mac, so I haven't used it in a while. Too bad the
source code for these plugins is not available. The papers on the website
only explain the basic principles.
Anyway, I also ran into the denormalization problem quickly, so I just made
a small VST that mixes some -100 dB white noise into the signal. Actually, I
made the noise gain adjustable, because the added noise made my
synth-guitars sound much more authentic. ;-)
Alternatively one could make it more convenient to use by creating a
separate wrapper .dll that loads the JCM900 and just intercepts the
process-calls, while passing any other call to the plugin.

Jan

> Also Guitarix seems to have a slight issue too, but thankfully MusE's
> basic anti-denormalization feature cured it.
> (Many thanks to Robert for the painstaking work on that feature!)
>
> Can I get some comments on an issue nagging me for years:
> Maybe I never learned some golden rule about floating point,
> please correct me if I'm ignorant of some crucial technique or fact
> which would help: ...
>
> I used to be fanatical about floating point (remember the co-processor
> days?)
> But I've grown to dislike it.
> Bankers won't use it for calculations.
> (Have you ever been stung by extra or missing pennies using a 'NUMBER'
> database field instead of a 'BCD' field? I have.)
>
> So why do we use floating point for scientific and audio work?
> Considering audio can have really small values, does it not lead to errors
> upon summation of signals?
> Why do we not use some sort of fixed-point computations?
>
> I mean take this simple BASIC program:
> LET A = 0
> LOOP: PRINT A
> A = A + 0.000001
> GOTO LOOP
>
> It produces the stupidest output with wandering errors after several
> iterations. A two-dollar calculator wouldn't do that.
> It plagued me when I worked with 3D drawing, too.
> You move an object incrementally several times in some direction
> but you can't get back to the original position by the reverse
> process. That's called 'non-return-to-zero'.
>
> > :).
> >
> > On the web page there are some PDFs.
> >
> > Perception and Congnition
> >
> > A perceptual approach on equalization
> > <http://www.simulanalog.org/eq.pdf>
> > A perceptual approach on clipping and saturation
> > <http://www.simulanalog.org/clip.pdf> Volume cranked up in amp debate
> > <http://www.trueaudio.com/at_eetjlm.htm> (by Brian Santo)
> >
> >
> > Numerical methods and models
> >
> > State variable changes to avoid non-computational issues
> > <http://www.simulanalog.org/statevariable.pdf>
> > A complete model of a tube amplifier stage
> > <http://www.simulanalog.org/tubestage.pdf>
> > Analysis and high performance simulation of linear networks
> > Polynomial interpolators for High-Quality Resampling (Olli
> > Niemitalo) <http://www.student.oulu.fi/%7Eoniemita/DSP/deip.pdf>
> >
> > Programming Techniques
> >
> > Optimizing with SIMD instructions
> > <http://www.simulanalog.org/optimization.htm>
> > Compiler Benchmarks <http://www.simulanalog.org/compiler.htm>
> >
> > I have little use for it, because of a lack of knowledge, dunno, perhaps
> > it's useful for some people from the list.
> Yesterday I took some time to read some of those papers.
> Fascinating stuff, especially when presented with an audio effects/amp
> simulation goal in mind.
>
> Tim.
>
> >
> > Thank you for the information Tim :),
> >
> > Ralf
>
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Received on Sun May 2 04:15:01 2010