Make the sound louder in Lubuntu

I have a Toshiba r835 running Lubuntu 11.10. Turning the volume slider up all the way doesn't give very loud sound. I've tried typing alsamixer in a terminal and turning up all the levels there to maximum, but the speakers are still fairly quiet. Is there a simple way to increase maximum volume in software?

I understand that there are physical limits to the sound the laptop's speakers can produce, but I suspect my maximum volume is limited by software.

EDIT:

This is exactly the type of solution I'm looking for. However, it doesn't work for me. What I did:

sudo pico /etc/asound.conf

This file does not exist, so I create a new one, containing:

pcm.!default {
      type plug
      slave.pcm "softvol"
  }

  pcm.softvol {
      type softvol
      slave {
          pcm "dmix"
      }
      control {
          name "Pre-Amp"
          card 0
      }
      min_dB -5.0
      max_dB 20.0
      resolution 6
  }

I reboot the machine, and type alsamixer. I use my left/right arrow keys to inspect the various volume options. I expect to see a new option, called Pre-Amp, but I don't see one. This fix seems to work for other people. Why doesn't this fix work for me?

You could try using PulseAudio. Simply install pavucontrol package and then play with volume levels through the settings menu of the regular volume control in the panel.

I am not sure it answers your question, however, when the sound on my laptop is not loud enough I generally go into the sound properties (there is a speaker icon on the upper right corner) and slides the pre-amplification to a higher value (over 100%). It can be convenient but it remains pre-amp (as VLC does for example) so depending on the situation in can deteriorates the sound.