Hi!
There is sfubar. It can do a bit with soundfonts and it is CLI. It ouputs
.WAV and a text file describing the configuration of the samples. But it is
not very advanced. I think it was mainly used to edit SF@-files for simple use
in csound.
Doesn't swami come with its own library of SF2 related functions? If not, I
believe it was Josh, who provided a lib for this purpose.
As to sample manipulation you're right there's more than enough. Ecasound
and its tools for the simple things and csound, supercollider or CLM for the
more complex tasks.
I hope, that this somehow is of help to you.
Best
Julien
--------
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