Was just looking at some old bookmarks buried in subfolders and came across a few links that I wanted to share.
First up is a clever tool for understanding frequency ranges in general and various musical instruments in particular. As you mouse over the various parts of the chart it then gives corresponding information in the boxes to the right. I'm not explaining it very well so you will just have to trust me and go check it out:
On a related note here is a useful page for understanding the dreaded Fletcher Munson Theory:
And finally a good read that is very helpful in understanding how and why to tame all those sound waves bouncing off the walls in your listening area: