For Noise Reduction
I like these
Koss Plugs
Great for Noise reduction.
They sound great (10-20,000 Hz), but are a bit hard to get used to at first. They are much less expensive than the equlivlant
Sony Fontopia and have replaceable plugs. The Fontopia have better range (6-23k Hz), but I don't think they sound much better. There is a badged version of the Koss Plugs at
RadioShack.
Open headphones are better for ear health. I like the Sony w's (the over the ear clip ons). Closed headphones create more back pressure on the ear. Also it's hard to hear outside noises that could help you avoid danger. I work with expensive closed cell AKG studio monitors and when I get home I want light and small.
These
Active noise reduction buds by Sony are also good, but I don't like the silicon ear inserts.
By the way, most humans hear between
20 and
20,000 Hz. Range is great, but not the entire story when it comes to a good set of headphones. Responce (how quickly a speaker can change frequency) and distortion are also important concerns. The equal loudness contour for a given frequency is not easly graphed, to further compound the dificulty of finding the "best" set of phones. The
Equal Loudness Countour shows the threshold of hearing at different frequencies and the apparent levels of equal loudness at different frequencies. I think that most people can
10Hz and below, but the impact is minimal though the ears. Thoes sounds are more "felt" than heard. The only reason that I convey this so that it is in the archive and so audiophiles don't tell you that your nuts if you find something that sounds great to you and not to them.