pcm.dmixout {
  type plug
  slave {
     pcm "dmix"
  }
}

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
  }