Increase max speaker volume in KDE 5 without installing additional software
Solution 1:
This is possible by accessing the Audio Volume widget's settings.
- Right-click the Audio Volume widget and open settings.
- Open the General Tab.
- Change max volume and volume step as per your needs.
- That's it. Now, increasing volume through the volume keys lets you reach volume levels greater than 100%.
Solution 2:
In newer versions of KDE Plasma (~ version 5.17), this option exists in Volume manager itself, as a checkbox at the bottom named "Raise Maximum Volume", allows volume upto 150%.