I wouldn't concern myself too much with the brand of speakers. I have opened up my fair share of notebooks with Harmon Kardon, JBL, etc. stickers on them. You would be disappointed to find that the speakers are often generic. JBL or HK paid to get their names attached to the notebook, but trust me there isn't anything special inside. The speakers Apple uses are custom designed to fit in the space available. Typically, the speakers are encased in an enclosure. Not sure if the enclosure is tuned, but I'm sure the enclosure improves the sound somewhat. There is really only so much you can do with the sound from a notebook. Designers are really limited by space (particularly in Apple notebooks). In the larger PC notebooks designers can install larger diameter drivers which is the only way you're going to get any respectable bass.