This Easy Effects preset tries to improve the sound of the built-in speakers.
It was created by following the excellent guide Enhancing your internal notebook speakers without using an Equalizer by Markus Schmidt. I couldn't find a rendered version online, but it's included in the Easy Effects help. The source can be found here. I highly recommend it!
With some bass-heavy music this preset can lead to distortions. You'll have to reduce the Amount of the Bass Enhancer effect to avoid that.
The preset approprate for Easy Effects prior to version 7.0 can be found in the easyeffects6 branch.