Hello Shintaro,
SM> does somebosy know how I can produce SID alike sounds in PD?
as far as i know (not a lot i'm affraid) SID is a subtractive synth based on triangle, square, saw and noise 8-bits signals.
there are also low-pass, high-pass, band-pass filters. now the hard part is that weird resonance filter that make this typical SID sound.
i don't think that emulating such a chip is hard but the way to handle the "instruments", the chip is not the most important part as the "power" of its sound has been mainly due to the trackers that were controlling it (ADSR, LFO, "oldskool effects" ...)
SM> I know I should first try it by myself, but maybe somebody else has SM> done that before (of course i think..)
not me, but if you're willing to give it a try, let me know cause i would be interested in making a such "l33t" patch ;)
++
aym3ric.