Is this a licence violation?

[ziqiangao]

I am trying to make a fluidsynth extension which depends on two libraries,
fluidsynth-emscripten which has the following LGPL-2.1 license

js-synthesizer which has the following BSD-3-Clause license

Are these two licences compatible with GNU General Public License version 3

[GarboMuffin]

those should be okay, just plop them into licenses if they aren't already in there and leave appropriate comments

i am sorry about the delay, everything is very slow, your choice of library was not the reason for the delay