$ sudo apt-get update
$ sudo apt-get install libladspa-ocaml 

libladspa-ocaml is installed in your system.

Make ensure the libladspa-ocaml package were installed using the commands given below,

$ sudo dpkg-query -l | grep libladspa-ocaml *

You will get with libladspa-ocaml package name, version, architecture and description in a table

libladspa-ocaml package basic information: