When I listen to music or play any video on firefox the audio stays very low despite of changing all the sound options to its maximum value in Gnome Alsa Mixer.
I have seen that when I use audacious with the Equalizer ON, the sound goes louder, but without that sound is very unsatisfactory.
There is an answer here
Simply execute:
Ubuntus audiosettings have a slider that allowes to rise the volume above 100%.
Ubuntu uses Pulseaudio as middleware on Top of ALSA. Alsa mixer won't do it. Install pavucontrol to control soundsettings. But it won't do much more as the ubuntu soundsettings already do.
If your problems resist you could possibly try ALSA without Pulseaudio by removing pulseaudio (Warning: May result in ALSA misconfiguration and no sound at all).
Coming into this years late, but I've got a Yoga 2 Pro that I can hardly hear. What I did was create a shell script called volup.sh that has this in it:
The "1" there is the value that works on my computer. You'll have to determine which channel your main audio is.
Then I set a keyboard shortcut tied to the volume up media key that overrides the normal volume up functionality and runs this script.
The normal increase volume functionality stops at 100%. But this will let you raise it as high as you want. To the point where it totally distorts out.