Well, most active and passive basses when you don't use EQ are very similar. After all, the front end of your head is basically an active preamp! An active bass merely moves part of that EQ circuit into the bass where it more convenient to adjust while you are playing.
In the Common Application, it says that the Personal Essay should be at least 250 words, and attached on a separate sheet (presumably, if you're submitting it online, you attach a one-page file).
Your essay should convey an interest and commitment to the research. Awards cover either a six or nine month period â be sure that your essay provides evidence that you will stick with the project for that period of time, and that the project has enough depth to keep you engaged during that period.