You actually should upsample, lowpass, distort, and lowpass again. The spectra of digital signals are periodic; it's technically not limited to the sample rate. The sample rate determines the size of the period. For real signals, you have frequencies from 0 to the Nyquist frequency, and then everything between Nyquist and the sample rate is a mirror image of the spectrum below Nyquist (you could think of them as the aliased frequencies). That defines one period, and it gets repeated further up the frequency range. In other words, you have the spectrum from 0 to SR, and that gets repeated at SR to 2*SR, and again at 2*SR to 3*SR, and so on.

Now, when you upsample, the parts of the spectrum above the original Nyquist will fall below the new Nyquist. And when you send it through [tanh~], those frequencies will produce new frequencies, some of which will alias in the new sample rate, and some of which will fall below Nyquist when you downsample back to the original sample rate. You probably don't want that. So, you'll need to filter after you upsample to remove the repeated spectrum. And the [tanh~] will produce so many partials that you'll need to filter again before you downsample.

I would recommend upsampling by a factor of at least 8. You'll still get some aliasing, but what gets aliased will probably get masked. I think Pd only lets you upsample by powers-of-two, so the next one would be a factor of 16. That should be high enough, though it could be cpu intensive. As for the filters, they should just be far enough below the original Nyquist so most or all of what is above it is filtered out. I would recommend using [lp10_cheb~] for this as it has a very steep roll-off. You could probably set it to about 18kHz without aliasing.

It depends on your OS. On Windows you have to specify in the installer that you want [csoundapi~] installed. The csoundapi~.dll file then gets installed in Program Files/Csound/bin, and the help file gets installed in Program Files/Csound/examples/csoundapi_tilde. Copy these files and the the csapi_demo.csd file to your Pd path. I can't remember where they are installed on OSX, but I found them through a Spotlight search. Not sure about Linux.

Csound can be awkward at first if you're not used to text-based idioms. There are a number of tutorials and example .csds included with Csound, as well as examples in QuteCsound. QuteCsound is a pretty nice frontend that is now included with the Csound installers, and if you're new to Csound I highly recommend using it. It is fairly new, so there are some bugs, but it seems to be in the most active development and the developers are on the Csound list every day. I recommend starting with Dr. Boulanger's TOOTs, Chapter 1 of The Csound Book, and Michael Gogins' "A Csound Tutorial" and working up from there. All of those are included with Csound and are freely available online.

The Csound list is very friendly and helpful, so it's a good resource if you need help. I'm also an admin at csounds.com. It's not nearly as active as the list, but feel free to hit me and others up on the forums there as well. Good luck!

As above,
[adc~]
| |
[pd frequency_stuff]
| |
[dac~]

where [pd frequency_stuff] can be filters (try lop~, bp~, hip~, vcf~, biquad~, etc.) or fft~ - based techniques (see the examples included with pd for a lot of good stuff.) Also recommended is the pd-extended build which includes pddp documentation (as well as a load of useful externals).

Good luck!

pdp...its ticky on osx...in fact Ive never got it to work ..the guy that wrote it is a good linux developer but hasnt got access to a mac...

I dont know what project your working on but as a fellow mac user I recomend you use GEM which is a very functional sent of video/3d/2d objects for PD. I cant compare the two but it seems that Gem does everything that I need...

now gridflow...that would be worth getting working on osx
...good luck

If you are running windows I recomend midiYoke.

http://www.midiox.com/index.htm?http://www.midiox.com/myoke.htm

> To start with, I'd recommend pd-0.39-2 from http://www-crca.ucsd.edu/~msp/software.html ,

that's the one I've got! (at least here, I'm right

>If you're happy using VST's to make soundscapes, then use them. Pd is more for you if you want to create sounds that no-one else has, IMHO, and have the flexibility to do almost anything

I know... but I still feel more confortable with a traditional language (C++, pascal), also
for writing my personal VSTs (you know, for those weirdest things...)
I think it's still easier to write "algorithms" with a textual language,
without a graphical metaphore.
But now I need to teach a course on "languages for electronic music" in classical, academic shool.
they don't know DSP matchematics or something like,
so I need to urgently search for use a more "abstract" instrument for doing the lessons...
Tried also Jmax but on Windows (required OS, because > 95% students use billgatesware ) is quite unstable.

cheers
l.

Can't help you with Windows-specific problems - I use Linux.

Check where you installed Pd: there should be a folder called "doc", look inside and you'll find examples that work and make sound. I count 132 files in /pd/doc/3.audio.examples/ - that should get you started.

To get a list of objects built into Pd, you can create a new patch, right-click on the empty space, and select "Help" from the menu. Or you can look in /pd/doc/5.reference where all the help patches are (you can also get them by right-clicking on an existing object and selecting "Help").

Out of curiousity, which Pd version did you get? To start with, I'd recommend pd-0.39-2 from http://www-crca.ucsd.edu/~msp/software.html , once you've reached the limitations of that then think about getting Pd-extended (which only has an unstable test version for 0.39 at present, and you really don't want to use 0.38 because it's hella crufty compared to 0.39).

If you're happy using VST's to make soundscapes, then use them. Pd is more for you if you want to create sounds that no-one else has, IMHO, and have the flexibility to do almost anything (I would bet that you could implement a Universal Turing Machine in Pd, I might even try it one day). Oh, and I believe you can use (at least some) VST's in Pd by using an external (a plugin for pd). I don't use Windows so I've never tried.

PS: it took me about 9 months before my first healthy pd-baby was born (the first audio track I was happy with). And I'm still learning how to work with Pd now.

PPS: Pd isn't released under the GPL - it has a much more liberal license that lets parts or all of it be used in proprietary software (like Max/MSP).

I love PD!

@megale said:

hello, cygwin or mingw are more recommended for compiling pd libraries under winslows

patco

thnks megale.... so I'll try a little more with Dev-C++ (it's bundled with mingwin and cygwin)...

but still, I need pd.lib, which I don't have.... i'll try to compile pd here...

hello, cygwin or mingw are more recommended for compiling pd libraries under winslows

patco