I found a Csound patch synthesizing sounds for a handpan on this page and it sounds great.
I then wanted to interface it with my MIDI controller so that rather than learning Csound from scratch, I've embedded the CSD synth into a Pd patch using the [csound6~] external. Works great.
The next steps however were to use such Pd patch on my smartphone via MobMuPlat, or in a DAW using plugdata (my attempt at generating a VST with Cabbage shows very poor CPU performance), however both are based on libpd and don't support [csound6~].
So I've taken the approach of reproducing the csound patch in vanilla Pd, which was very instructive. I've followed the same variable, function names and logic, read a lot of documentation, and came up with the patch attached.
However, the sound is not quite the same. There is a huge lot of high frequencies in the Pd version, which I couldn't quite eliminate even using up to 10 successive [lop~ 900] (I've left only one in the patch for now), but more generally I can't figure which differences between the csound patch and the patch may have this effect. Note that I am neither an expert in Csound or in filters - in particular I don't quite trust the Butterworth3 filter I hacked together - can I even realistically expect that the same algorithmic logic in Csound and Pd would produce the exact same sound?
So I'm now asking here for help, in case some experts may find the time to review what I've done in Pd and compare it with the Csound patch, and may be able to suggest improvements. I know it is quite tedious work but I am hopeful Thanks in advance to anyone who gives it a try!
(Note that this patch was embedded in a more complicated one including interfacing with the midi controller, definition of various scales, debugging/monitoring etc., which I've removed before sharing it here, but I may have forgotten some bits here and there, let me know if it complicates the review!)