I'd disagree, as my volume is only on about a quarter, and it's plenty loud enough (probably even too loud, dare I say it!).
The guitarist used to use a Marshall solid state 150 stereo rig, and the Ashdown was plenty loud enough then. He moved to a 20w valve Marshall head through a 4x12, and again, it's plenty loud enough. Depending on the situation, I may have to raise or lower the volume, but never by very much.