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).
How long should the essay or statement be? Your essay should never exceed the limit given in the application instructions. If no limit is specified, make your essay no longer than two pages. How much of the information already in my application should I repeat? Admissions reviewers may not read every detail of your application carefully.