I'm also pretty sure that the level in hardy is generally lower than it
was on gutsy.
It may be due to Pulse Audio. Shutting it down might help.
I also noticed that some alsa levels are set to about 80% by default,
but I don't know if it's safe to turn them all the way up.
In general, high levels should be achieved by gear that comes after the
computer, not inside it. If you're as poorly equipped as me, that's not
possible. I did turn up the alsa-levels all the way, and that's quite
o.k, most of the time.