This article is intended as a starting guide for purchasing a pair of studio monitors and do a basic acoustic treatment of the studio room. I recommend reading the reviews for various monitors. It’s useful to listen to several models before choosing a pair / set. http://www.producerspot.com/tips-about-studio-monitors-and-acoustic-treatment
Learning about acoustics and how to setup monitors http://www.soundproofcow.com/Soundproofing-101/
Quick Instrument Frequency Chart - good place to start... Verify!!!