Qsynth is a free and open source softsynth management application for Linux and Windows. Using Qsynth you can control and manage a variety of command line softsynths. It is a fluidsynth GUI front-end application written in C++ around the Qt framework using Qt Designer. It is released under GNU General Public License (GPL) version 2 or later. fluidsynth is a synthesiser application based on the Soundfont specification.
Install Qsynth on Ubuntu Linux
Download Qsynth in .AppImage file format from the above download link and save it on your Downloads folder. Now open the terminal (ctrl+alt+t) command line application and run below commands one by one.
sudo chmod +x ~ qsynth-0.9.6-50.1.x86_64.AppImage
Install Qsynth via Flatpak:
Qsynth also available from flathub as a flatpak package file. First install flatpak and flathub. In your terminal run below Qsynth flatpak installation command.
flatpak install flathub org.rncbc.qsynth
You can open it via below command or via the applications menu.
flatpak run org.rncbc.qsynth
You can also uninstall it via below command
sudo flatpak uninstall org.rncbc.qsynth