No offence to the OP or anything, it's a question that i can understand why people would want an answer too.
But good sounding speakers need large enclosures (especially for lower frequencies), large and expensive drivers, and a solid consistent power supply.
The ipad, any other tablet, phone or laptop does not have any of these features. Notice how bigger laptops have better sound ? it's simple, they have bigger enclosures so can create deeper notes, so they sound 'fuller', and the tinnyness that people correctly associate with bad sound quality is lessened.
Sure, they could probably make the iPad 2 speaker louder, but it could damage the speaker and be even more horribly distorted than the first one. This isn't a bash at apple, it's physics, you just can't do it. If they prioritised sound over battery life or something else so they could give it a larger enclosure inside the case, then yes, it could sound better and louder. But how likely are they to do that ? it's not going to happen.
That all said, there are a few ways that you can increase speakers loudness. It has negatives, such as making it sound a bit weird and not quite how it should, but it does make it louder.